FDG-PET

In brief

What the scan is

FDG is glucose with one change ¹. In 2-deoxy-2-[¹⁸F]fluoro-D-glucose, the hydroxyl group that ordinary glucose carries on its second carbon, an oxygen bonded to a hydrogen, has been replaced by an atom of radioactive fluorine-18 ¹. The swap is small enough that the body's sugar-handling machinery largely accepts it: fluorine is electronically closer to a hydroxyl group than is the bare hydrogen of the parent compound, 2-deoxyglucose, so the molecule behaves more like glucose ¹. Cells take it in through their glucose transporters, the protein doorways in the cell membrane, and the first enzyme of sugar metabolism, hexokinase, attaches a phosphate to it just as it would to glucose ^3,31.

PET, positron emission tomography, is the camera ². Fluorine-18 decays by emitting a positron, the antimatter twin of the electron; the positron travels a millimeter or two, meets an electron, and the pair vanishes into two photons that fly off in opposite directions ². A ring of detectors around the patient records pairs of photons that arrive within a few billionths of a second of each other, and a computer reconstructs where in the body the decays happened ². The isotope's half-life is 109.7 minutes ³, long enough that FDG can now be made at central sites and shipped to scanners that have no particle accelerator of their own ⁴.

What the finished image shows is not cancer ³¹. It is a map of where the tracer has been trapped about an hour after injection, the standard wait ³. Tumors often stand out because many of them convert glucose to lactate far faster than the tissue around them, which Otto Warburg measured in the 1920s ³⁷. But a review written to explain the scan's success states its limit in one sentence: uptake is relatively nonspecific, since all living cells need glucose ³¹. Brain, heart, kidney and bladder, inflamed tissue, healing tissue and active brown fat all collect it ^1,26,34,36. Reading a PET scan is the work of deciding which of those a bright spot is ²⁶.

From a rat's brain to every cancer center

The tracer was not built for cancer ⁴. In 1977 Louis Sokoloff's group published a method for measuring how fast each region of a rat's brain uses glucose, using carbon-14-labeled deoxyglucose and autoradiography, in which thin slices of tissue expose photographic film ⁴². It worked because a 2-deoxy sugar is phosphorylated and then goes no further, so radioactivity piles up wherever glucose is being taken in ¹. Doing the same in a living person needed an isotope whose radiation escapes the body, and a camera to locate it ². The camera existed by 1975 ⁴³. The tracer was developed in 1976 by scientists at the National Institutes of Health, the University of Pennsylvania and Brookhaven National Laboratory, where the chemists Tatsuo Ido, Alfred Wolf and Joanna Fowler made it, for one purpose: mapping glucose use in the living human brain ^4,5.

Oncology came in sideways. Animal studies published in 1980 showed rapid uptake in transplanted and spontaneous tumors ⁴⁴, and in 1982 Giovanni Di Chiro and colleagues reported that high-grade gliomas, aggressive brain tumors, used glucose faster than low-grade ones ⁴⁵. Two developments turned an experiment into a hospital test ⁴. A 1986 synthesis using fluoride ion rather than fluorine gas gave yields of up to 50% in about 50 minutes ⁴⁶, and production moved to central sites that ship the drug ⁴. Then, in 2000, a PET scanner and a CT scanner were mounted in a single gantry, so every hot spot came with an anatomical address ⁸. By 2008, a Medicare registry had collected 22,975 scans from 1,178 American centers in a single year ²¹.

The reversals arrived alongside the adoption, and most concern the same mistake: treating trapped glucose as proof of cancer ³¹. In 1992, microscopic autoradiography of mouse tumors showed macrophages and granulation tissue holding more FDG than the cancer cells ²³. In 2014 a meta-analysis found that the scan's specificity for lung cancer fell to 61% where infectious lung disease is common ⁹. The parasite literature, mostly from the last twenty years, has had to give up one confident reading after another: that a dark lesion means a dead parasite, that a very bright one means cancer, and that scanning again later separates the two ^30,32,47.

How the sugar is trapped and the light is counted

Glucose that enters a cell is phosphorylated by hexokinase into glucose-6-phosphate, and the next enzyme, phosphoglucose isomerase, rearranges it into fructose-6-phosphate on the way down glycolysis, the pathway that splits sugar for energy ¹. A 2-deoxy sugar lacks the hydroxyl on carbon 2 that this step needs, so its phosphate cannot be isomerized and builds up inside the cell, held there by its electrical charge ¹. Fluorine is the clever part. Hexokinase tolerates almost no chemical change at carbon 2, yet 2-deoxy-2-fluoro-D-glucose was a good substrate for the yeast enzyme in 1972 experiments ³⁸, and the fluorinated sugar is a more efficient substrate for hexokinase II than 2-deoxyglucose itself ¹. Brookhaven's chemists named the principle metabolic trapping ⁵⁰.

The trap leaks a little ⁷, and where it leaks matters. An enzyme called glucose-6-phosphatase can remove the phosphate again; the 1979 human validation found this reverse step small but significant in brain ⁷. In 17 hepatocellular carcinomas, cancers of the liver's main cells, uptake tracked hexokinase activity (correlation coefficients r = 0.715 and 0.768, where 1 would be a perfect match) and was higher in high-grade tumors, but relatively high glucose-6-phosphatase activity reduced retention in some ⁶⁷. Uptake also rises with the number of glucose transporters and the activity of hexokinase, and hypoxia, low oxygen inside a tumor mass, pushes cells further toward glycolysis ³¹. None of these properties belongs to cancer cells alone ^23,31.

The camera's task is geometric. A fluorine-18 positron travels typically 1 to 2 mm before it meets an electron; the two annihilate into two photons of 511 keV each, kiloelectronvolts being a unit of energy, moving apart along an almost straight line ². Scintillator crystals, which flash when a photon strikes them, sit in a ring around the patient, and when two register photons within a short coincidence window, typically 1 to 10 nanoseconds, the event is assigned to the line joining them ². The first such machine, the PETT of 1975, used a hexagon of 24 sodium iodide detectors wired to coincidence circuits, which its builders called electronic collimation: instead of lead channels that admit only photons traveling in one direction, the requirement that two detectors fire together does the sorting ^43,48. Modern time-of-flight scanners also use the tiny difference in arrival times to place the annihilation along that line ².

Raw counts are not yet an image ². Photons are absorbed and scattered by the body on the way out, and chance coincidences between unrelated decays add noise, so every scan must be corrected for the particular patient ². On a PET/CT scanner, the CT supplies that correction as well as the anatomy ⁸. The newest machines lengthen the ring: the EXPLORER scanner's 194-cm field of view covers the whole adult body in more than 99% of the population, and its sensitivity allows diagnostic images with 25 MBq of tracer or less, or acquisitions of about a minute ⁵⁶. Five of that paper's authors list affiliations with United Imaging Healthcare, a scanner manufacturer ⁵⁶. The scanner was cleared by the United States Food and Drug Administration (FDA) in 2019, and by late 2024 more than 50 long-axial-field systems were in clinical use worldwide, according to a review from the same Davis group ⁶⁸.

The number on the report

Most reports carry a number, the standardized uptake value ³. It is the concentration of radioactivity in a region divided by the injected activity spread evenly over the patient's body weight, so a value of 1 means the region holds exactly its share and 5 means five times its share ³. SUVmax is the value in the single voxel, the small three-dimensional pixel of the image, with the highest uptake ³. The European guideline also recommends reporting SUL, the same measure normalized to lean body mass instead of total weight ³. In 1995, an editorial asked in its title whether SUV stood for 'standard uptake or silly useless value' ⁵².

The number depends on how the scan was done as much as on the lesion ³. The guideline asks for at least four hours of fasting, a 60-minute wait between injection and scanning (acceptable range 55 to 75 minutes), the same wait to within 10 minutes when a patient is scanned again, and scanner settings harmonized between centers ³. Timing alone can change the verdict: in alveolar echinococcosis, a tumor-like tapeworm infection of the liver, a second acquisition at three hours changed the interpretation of 32.5% of 120 scans ⁴⁰. How much a number can be trusted also depends on how bright the lesion is: a 2023 meta-analysis of 11 test-retest studies found that the scan-to-scan fluctuation in SUVmax, SUVmean and SUVpeak (the brightest point, the average, and the brightest small neighborhood) of the same untreated tumor falls as uptake rises, so a 30% change means more in a bright lesion than in a faint one ⁶⁹. The table below lists the factors with published sizes.

Thresholds borrowed from one population fail in another ³². A commonly used cutoff for lung nodules, SUVmax 2.5, gave a specificity of 25% in a South African tuberculosis-endemic series ⁴⁷ and 34.7% in 191 Indian patients, in whom tuberculous nodules reached SUVmax 22.5 ³². Response criteria rely on change rather than absolute values ⁵⁵. PERCIST, proposed in 2009, treats a 20% change as the smallest that is statistically real in careful test-retest studies and requires a 30% fall for a response, measured in a fixed region of about 1 cm³ against a liver reference ⁵⁵. Lymphoma practice uses a five-point scale, and the Lugano recommendations made PET/CT the staging test for lymphomas that take up FDG ²².

More than one number can be extracted ⁶³. Dynamic imaging with Patlak analysis follows the tracer over time and separates FDG that has been trapped from FDG still circulating in blood ⁶³. In 20 data sets from patients with alveolar echinococcosis, it gave a lesion-to-liver ratio of 3.2 against 1.8 for the standard SUV ratio ⁶³. One of its authors is affiliated with GE Healthcare, a scanner manufacturer, a commercial interest in the technique ⁶³. The original FDG method was kinetic too, built on rate constants for transport, phosphorylation and dephosphorylation ⁷; the single static SUV is a clinical shortcut taken from it.

• FDG-PET/CT, standard one-hour scanWhole-body imaging about 60 minutes after injection, after at least 4 hours of fasting ³.The routine scan for staging and restaging many cancers, and the staging test for FDG-avid lymphomas ^3,22For lung nodules, pooled sensitivity 89% and specificity 75%, with specificity 61% where infectious lung disease is endemic ⁹.Low-glycolysis and small tumors and lesions beside bright organs ²⁶; brain lesions colder than cortex ²⁸; and it cannot separate infection, inflammation or a parasite's host reaction from cancer ^23,32.
• Delayed or dual-time-point FDG imagingA second acquisition after the same injection, at 90 minutes to 3 hours ^40,72.Follow-up of alveolar echinococcosis at specialist centers ⁴⁰Changed the reading of 32.5% of alveolar echinococcosis scans ⁴⁰; uptake stable or falling in 16 of 17 patients with bacterial osteomyelitis ⁷².Tuberculomas rose as much as cancers, so it cannot separate granulomas from tumor ⁴⁷.
• Dynamic whole-body FDG with Patlak analysisImaging over time that separates trapped from circulating tracer ⁶³.Research useLesion-to-liver ratio 3.2 against 1.8 for the standard SUV ratio in 20 alveolar echinococcosis data sets ⁶³.A small series with an author affiliated with the technology's manufacturer; not shown to tell a parasite from a tumor ⁶³.
• FAPI PETGallium-68 tracers that bind fibroblast activation protein on cancer-associated fibroblasts ⁵⁷.Specialist and research use; not yet in routine guidelines ⁶⁶Primary gastric cancer: area under the curve 0.96 against 0.76 for FDG in head-to-head studies ⁶⁶. Sensitivity 98% against 79% across 31 upper-abdominal studies ¹¹⁰.Specificity no better than FDG in upper-abdominal cancers, 83% against 87% ¹¹⁰; 2,372 reported nonmalignant uptake findings ⁶¹, and a cerebral hydatid cyst at SUVmax 6.0 ⁹⁸.
• PSMA PETTracers for prostate-specific membrane antigen, used in prostate cancer ⁵⁸.Staging high-risk prostate cancer and detecting recurrence; approved agents and a joint European and American procedure guideline ^58,11792% accurate against 65% for CT and bone scanning in a randomized trial of 302 men ⁵⁸.Uptake in benign conditions ¹¹⁸, including the walls of neurocysticercosis cysts ⁹⁴ and the rims of amebic liver abscesses ¹¹⁹.

Why infection and inflammation light up

The bright spots that are not cancer have a cellular explanation, and it was found inside tumors ²³. In mice carrying a transplanted tumor, microautoradiography an hour after injection showed newly formed granulation tissue, the soft repair tissue that fills a wound, and macrophages crowding around dead tumor tissue holding more FDG than the living cancer cells; up to 29% of the tumor's glucose use came from non-tumor tissue ²³. Three years later the same Japanese group induced abscesses in rats with turpentine and found the densest tracer in young fibroblasts, blood-vessel lining cells, neutrophils and macrophages, with uptake peaking four days after the injury ³⁶. These are mouse and rat experiments, but they name the cells: the repair and defense crew of inflammation ^23,36.

Not every activated immune cell is equally hungry ⁷⁰. In cultured mouse macrophages, bacterial lipopolysaccharide raised deoxyglucose uptake 2.5-fold, but the classical inflammatory (M1) and the repair-type (M2) activation programs did not, and M2 cells instead built 4.6-fold more mitochondria ⁷⁰. That would predict a quiet scan around any parasite that pushes macrophages toward M2 ⁷⁰. Yet when larvae of the fox tapeworm, Echinococcus multilocularis, did exactly that, the macrophages switched on three enzymes of glycolysis, hexokinase 1, a phosphofructokinase and a pyruvate kinase (HK1, PFKL and PKM2) ⁷¹, and macrophages, identified by their CD68 surface marker, crowded the liver tissue beside patients' lesions ⁷¹. The two cell-culture findings disagree, use different stimuli and readouts, and neither measured FDG in a parasitic lesion ^70,71.

In patients, the effect is best measured in the lung ^9,53. A 2001 meta-analysis of 40 studies and 1,474 lesions put FDG-PET, as practiced, at about 96.8% sensitivity and 77.8% specificity, so roughly one benign lesion in five read positive ⁵³. A 2014 meta-analysis of 70 studies and 8,511 nodules found pooled specificity of 75%, falling to 61% in regions with endemic infectious lung disease against 77% elsewhere; its authors concluded the data did not support using FDG-PET to diagnose lung cancer in endemic regions unless an institution could match nonendemic accuracy ⁹. In a South African series of 30 nodules, benign lesions averaged SUVmax 11.02 and cancers 10.86 ⁴⁷.

Waiting does not reliably help. Scanning twice after one injection rests on the theory that cancer keeps accumulating tracer while inflammation fades ^47,72. In chronic bacterial osteomyelitis the theory held: uptake was stable or fell in 16 of 17 patients while it rose in bone cancers, and the one exception had foreign-body granulomas, tight balls of immune cells built around material the body cannot clear ⁷². In the tuberculosis series, benign and malignant nodules rose by 17.1% and 19.4% between the two time points, with no meaningful difference ⁴⁷. Granulomas are also what the pathology of several parasite cases on this page describes ^12,73,74, and no study cited here tested whether dual-time-point imaging separates a parasitic lesion from a tumor; the one parasitic series that used delayed imaging ⁴⁰ compared active with inactive alveolar echinococcosis, not parasite with cancer.

Some of the brightness is simply physiology or medication ^34,35. In 3,640 scans from 1,972 patients, brown fat, the heat-producing fat of the neck and upper chest, took up tracer at SUVmax 2.0 or more in 7.5% of women and 3.1% of men, more often in younger people, in cold weather and in people not taking beta-blockers ³⁴. Vaccination does it too: across 25 studies and 5,010 scans after COVID-19 vaccination, reactive armpit nodes lit up in 38.6%, at a mean SUVmax of 2.8, more often in women and younger people; a stricter reading threshold cut that to under 20% ⁷⁵. Immunotherapy with checkpoint inhibitors, drugs that release the brakes on the immune system, adds another layer, because the inflamed organs it provokes (thyroid, bowel, lungs, joints) glow and can be mistaken for progression ⁷⁶. Metformin fills the bowel with tracer ³⁵. And in a parallel field FDG is used on purpose to find infection: an Italian consensus summarizing 291 papers covers osteomyelitis, endocarditis, tuberculosis, fever of unknown origin and more, while noting that standardization in that field is still lacking ⁷⁷.

The parasites that light up

Every parasite named here has been reported to light up on FDG-PET somewhere in the body, and nearly every report is a single case or a small series ^11,12,13,17. Their value lies less in their number than in their pattern ^16,33. In a ruptured lung hydatid cyst, the first report to correlate the scan with histology showed no metabolic activity inside the cyst and hypermetabolism, that is, bright uptake, in the inflamed lung around it ³⁹; in 17 proven pulmonary hydatid cysts, 10 showed a doughnut sign, a bright rim around a dark center ³³. Amebic liver abscesses appeared as cold holes edged with faint brightness ¹⁶. The light sits where the host is fighting, not where the parasite is ^39,40. The one parasite mimic with a pooled count is a protozoan: in visceral leishmaniasis, diffuse splenic uptake read as lymphoma appeared in 43 of 50 published cases and in all four seen at one Barcelona hospital ²⁰.

The parasite is not metabolically silent, which is why the accurate summary is mostly host, not entirely host ^78,79. Live adult Schistosoma mansoni took up FDG in a dish in proportion to their number, and in athymic mice, which cannot mount a normal T-cell response, portal-vein FDG tracked worm burden (R² = 0.85 in mice with more than 50 worms) ⁷⁸. In immunocompetent mice, FDG-PET/CT could not distinguish infection grades, and only the spleen differed from controls ⁸⁰. A glucose transporter of the fox tapeworm, EmGLUT1, carries 2-deoxyglucose when expressed in frog egg cells ⁷⁹. None of the studies cited on this page measures the worm's own share of the signal in a human lesion.

In the reports found here, the cost fell on people who already had, or were suspected of having, cancer ^12,13,17. A woman with cecal cancer (cancer of the first part of the colon) received 12 courses of chemotherapy for what PET showed as liver metastases before a resection found Fasciola hepatica, a liver fluke ¹³. A woman treated for ovarian cancer had liver masses read on PET as recurrence and was operated on for what proved to be Strongyloides stercoralis, a parasitic roundworm ¹⁷. A man with pancreatic and liver lesions at SUVmax 4.39 and 4.13 had surgery for presumed metastatic pancreatic cancer and was found to have chronic pancreatitis and old hepatic schistosomiasis with granulomas ¹². The table summarizes what each parasite was taken for; the tabs give the detail.

When the scan reads low

False negatives are quieter than false positives and matter as much ²⁶. A 2006 review listed the tumors that often read low because their glycolysis is modest: adenomas, bronchioloalveolar carcinomas (an older name for slow-growing lung adenocarcinomas that creep along the air-sac walls, a pattern called lepidic; the term was retired in 2011 ¹⁰⁸), carcinoid tumors, low-grade lymphomas and small tumors, along with lesions sitting next to organs that are normally bright, such as heart, bladder, kidney and liver ²⁶. The 2001 lung meta-analysis noted that few data existed for nodules smaller than 1 cm ⁵³. Low-grade gliomas in 1982 showed no distinct hot spot ⁴⁵, some hepatocellular carcinomas release the tracer through glucose-6-phosphatase ⁶⁷, and in stomach cancer the diffuse and mucinous types are a recognized weak point ⁶⁶.

Blood sugar is a confounder because glucose competes with the tracer, and insulin drives glucose into normal tissue ^1,3,41. In five head and neck cancer patients scanned fasting and again after oral glucose, tumor SUVs fell from 4.1–10.9 to 2.2–5.9 and image quality became markedly poorer ⁴¹. Guidelines responded with glucose ceilings that, by a 2018 count, ranged from 120 to 200 mg/dL ¹⁰⁹. The evidence has since loosened the rule ²⁷. A meta-analysis of 20,807 individual SUV measurements in 8,380 patients found no significant correlation between blood glucose and tumor SUV, and a significant fall only above 200 mg/dL, although brain and muscle uptake fell and liver and blood-pool uptake rose with hyperglycemia ²⁷. The European guideline says hyperglycemia should not be an absolute contraindication ³.

In the brain the problem is contrast ²⁸. Normal cortex is so avid that a lesion must outshine it to be seen, and in people with HIV, toxoplasmosis lesions read below cortex while lymphoma read far above it ²⁸. That separation is useful, but a cold brain lesion is not always an infection ^24,25. A woman with lung cancer whose cold brain lesions were treated as neurocysticercosis had one that was a metastasis ²⁴. A man with a raw-food diet, a positive parasite antibody test and low glucose metabolism on FDG-PET was treated for parasitosis and kept worsening; surgery confirmed glioblastoma, seven years after his symptoms began ²⁵.

Among parasites, a cold scan has repeatedly been mistaken for a quiet one ^30,59. In alveolar echinococcosis, lack of metabolic activity 'is not equivalent to parasite death' ³⁰, and standard one-hour images missed activity that delayed images found in 11 of 44 patients followed for more than two years ⁴⁰. A viable hydatid cyst was FDG-negative ⁵⁹. In cerebral alveolar echinococcosis, FDG missed 11 of 35 lesions that a choline tracer found ⁹⁶. A cold nodule does not end the matter in the lung either: an FDG-negative dirofilarial nodule and a non-avid cysticercosis nodule were both removed or biopsied, and both were parasites ^92,107.

What is done about it, and the tracers that may replace it

Much of what is done about FDG's blind spots happens before the injection ³. Patients fast for at least four hours, blood glucose is measured before the tracer is given, and the interval between injection and scanning is held at about an hour so that numbers can be compared ³. Metformin can be paused: in the randomized trial, 48 hours off the drug lowered large-bowel uptake more than 24 hours did, but raised blood glucose on the day of the scan from 123 to 151 mg/dL (6.83 to 8.41 mmol/L) ³⁵. Drugs to suppress brown fat, such as intravenous diazepam or oral propranolol, have been tried with conflicting results ³.

The rest is interpretation, and the parasite literature shows what helps ^16,33. The geometry of the signal is a useful clue: a bright rim around a dark center pointed to hydatid disease or amebic abscess rather than metastasis ^16,33, and in the amebic case that atypical pattern is what prompted the biopsy ¹⁶. Travel and diet history, eosinophil counts, serology and stool examination supply what the scan cannot ^100,103, and the stool method matters: a fluke infection was missed by a flotation test and found by formalin-ether concentration ¹⁰³. In schistosomiasis, the Danish authors wrote, PET supports only a presumptive diagnosis built on travel history and exclusion of other causes ¹⁰⁰. When surgery or chemotherapy is at stake, tissue decides ^13,39.

Newer tracers aim at something other than sugar ^57,58. FAPI tracers bind fibroblast activation protein, made by the cancer-associated fibroblasts in a tumor's supporting tissue; in 80 patients with 28 tumor types, sarcoma and esophageal, breast, bile-duct and lung cancers had average SUVmax above 12, against background below 2 in muscle and blood ⁵⁷. A 2026 meta-analysis of 14 studies in gastric cancer found FAPI more accurate than FDG head to head, but recommended it only as a complement, with prospective multicenter studies needed before it enters guidelines ⁶⁶. Across 31 studies of pancreatic, liver and gastric cancer, FAPI was more sensitive than FDG (98% against 79%) but not more specific (83% against 87%) ¹¹⁰; in bile-duct cancers it detected tumors with a pooled odds ratio of 4.9 over FDG ¹¹¹; in lung cancer lymph nodes its area under the curve was 0.97 against 0.80 ¹¹²; and in the first prospective two-center study, 61 women with breast cancer, it found every primary tumor where FDG found 79%, and changed management in 15% ¹¹³. Fibroblasts gather wherever tissue scars, though ⁶¹, and FAPI is now being tried on purpose to image inflamed, fibrosing bowel ¹¹⁴. A systematic review listed 2,372 FAPI-avid findings that were not cancer, among them arterial plaque, arthritis, tuberculosis and IgG4-related disease, a fibrosing inflammatory condition ⁶¹, and a brain lesion that MRI suggested was a glioma took up FAPI and proved at surgery to be a hydatid cyst ⁹⁸.

PSMA tracers bind prostate-specific membrane antigen, and in prostate cancer they have randomized evidence ⁵⁸. Unlike FAPI, PSMA PET is already routine care: gallium-68 PSMA-11 and fluorine-18 piflufolastat are approved imaging agents in the United States ^115,116, a joint European and American procedure guideline, version 2.0, governs their use ¹¹⁷, and the same target is treated with lutetium-177 PSMA-617, an approved radioligand therapy ¹¹⁶. In the proPSMA trial of 302 men, PSMA PET/CT staged high-risk disease with 92% accuracy against 65% for CT and bone scanning, with 8.4 mSv of radiation against 19.2 mSv ⁵⁸. The name overstates the specificity: the protein acts as a folate hydrolase and is present in other benign and malignant conditions ¹¹⁸; it lit the walls of neurocysticercosis cysts in a man with prostate cancer ⁹⁴, and in 2025 the rims of amebic liver abscesses that had been read as necrotic metastases ¹¹⁹. In parasitic brain lesions, amino-acid and choline tracers have done better than FDG in small series: carbon-11 methionine was not raised in three cysticercosis lesions ⁹³, and a choline tracer found all 35 cerebral alveolar echinococcosis lesions where FDG found 24 ⁹⁶.

What was believed and is not

Most of the corrections on this page do not show a test that failed; FDG-PET remains sensitive for lung cancer, at 89% pooled across 70 studies ⁹. They show a test asked a question it was never built to answer ³¹. FDG measures glucose trapping, and cancer, infection, repair and normal physiology all trap glucose ^26,34,77. Each belief below assumed the scan could see something more specific than that, and each was corrected by a study that looked at what was actually glowing ^23,30,59.

None of this makes FDG-PET a poor test ²². In lymphoma it now decides stage and response ²², in alveolar echinococcosis it predicts the course of the disease ⁶² and guides when drug treatment can safely stop, together with serology ^40,65, and in the Medicare registry it changed physicians' intended management in 36.5% of cases ²¹. The registry measured intended plans, not patient outcomes ²¹, and a changed plan is only a better plan if the scan was right.

What is still unknown

The central unknown for this season is how much of a parasitic lesion's signal comes from the parasite ^78,80. The animal and cell evidence says the worm can take up FDG: schistosomes did so in a dish and in T-cell-deficient mice ⁷⁸, and a fox tapeworm transporter moves 2-deoxyglucose ⁷⁹. Adult schistosomes even resemble Warburg's tumors metabolically, using glucose and producing lactate at the same rate with or without oxygen ¹²⁰. But in mice with normal immunity FDG failed to grade schistosome infection ⁸⁰, and in human lesions the uptake sits in the inflamed rim ^39,40. None of the studies cited here separates parasite counts from host counts in the same human lesion.

No study found for this page counts how often parasites cause false-positive cancer scans. The meta-analyses that quantify infection-related false positives are built on lung nodules and dominated by tuberculosis and other lung infections ^9,32, and the parasite literature is almost entirely case reports ^12,13,17. Whether the 16-point fall in specificity seen where infectious lung disease is endemic ⁹ has a counterpart where flukes, tapeworms or schistosomes are common has not been measured in any study cited here.

Several mechanistic questions are open. Cell studies disagree about whether repair-type macrophages, the kind the fox tapeworm provoked in culture, take up more glucose ^70,71. Delayed imaging helps in alveolar echinococcosis ⁴⁰ but failed for tuberculomas ⁴⁷, and no series cited here tests it in other parasitic lesions. Whole-body scanners ⁵⁶ and kinetic methods ⁶³ improve contrast, but neither has been shown to tell a granuloma from a tumor.

For the alternatives, the evidence is younger than the enthusiasm ^61,66. FAPI's advantage in gastric cancer rests on 14 mostly small studies with possible small-study effects ⁶⁶, and across upper-abdominal cancers its gain is in sensitivity, not specificity ¹¹⁰. Its behavior in parasitic infection is known from a single case ⁹⁸. PSMA's from two, a neurocysticercosis case and an amebic abscess case ^94,119. The choline result in cerebral echinococcosis comes from eight patients at one center ⁹⁶. Even in prostate cancer, where PSMA has a randomized trial, that trial measured staging accuracy and changes in management, not survival ⁵⁸.

How it connects to parasites and cancer

Stated at its true strength, the link is this: FDG-PET does not detect parasites, and it does not detect cancer; it detects glucose trapping, and around a parasite most of that trapping appears to belong to the host ^31,39,40. That makes the scan a place where the two diagnoses this season is about can be mistaken for each other, in both directions, and documented cases exist on both sides: parasites treated as cancer ^12,13,17 and cancers treated as parasites ^24,25.

The hardest cases are those in which the parasite is also linked to cancer ^14,101. Clonorchis sinensis, a liver fluke that is an established cause of bile-duct cancer ¹⁰², produced liver and lymph-node uptake with a raised CA19-9 and was first diagnosed as cholangiocarcinoma ¹⁴. A man with bladder cancer associated with schistosomiasis had hypermetabolic lung nodules; the largest, resected as a suspected metastasis, showed silicosis and tuberculosis ¹⁰¹. In such patients a positive scan cannot say whether the parasite has caused a cancer or is inflaming the tissue around it ¹⁴; in the bladder cancer case the answer came from histology and molecular testing ¹⁰¹.

For the season's question, whether the cancers attributed to parasites are the real number or only the number anyone has looked for, the scan matters in a specific way, because PET results change what happens next ²¹. In the Medicare registry, a biopsy that had been planned was avoided in about 70% of cases after PET ²¹. When a lesion's label is never checked against tissue, it rests on the scan, and the cases above show the scan can be wrong in either direction ^13,24. That is a reason for caution about imaging-based counts in regions where parasites are common, not evidence that any published count is wrong.

What the evidence does not support is the opposite overstatement: FDG uptake in a cancer patient is not evidence that a parasite is present or active, and a parasite-like scan is not evidence that a cancer is absent ^24,25. In alveolar echinococcosis, a parasitic disease that behaves like a tumor, FDG is a valuable activity marker in specialist hands ^10,83. Elsewhere its role is to raise the question; the answer comes from history, serology, stool and tissue ^100,103.

Where it connects

Sources

120 sources, numbered as they are cited. Every one was checked against PubMed or its publisher before it was cited here; the note under each says what it shows and what it does not.

1. 1
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   Review (full text read) explaining that a 2-deoxy sugar phosphate cannot be isomerized to fructose-6-phosphate and accumulates, and that fluorine mimics the hydroxyl; the authors' laboratory develops a 2-DG analog licensed to Moleculin, a commercial interest in this chemistry. PubMed dates the record 2019; its print issue, 21(1), belongs to 2020.

2. 2
   Vaquero JJ, Kinahan P. Positron Emission Tomography: Current Challenges and Opportunities for Technological Advances in Clinical and Preclinical Imaging Systems.Annu Rev Biomed Eng · 2015 · 17:385-414doi:10.1146/annurev-bioeng-071114-040723 · PMID 26643024

   Engineering review (full text read) for the physics: 1 to 2 mm positron travel, 511 keV photon pairs, 1 to 10 ns coincidence windows, time of flight and corrections.

3. 3
   Boellaard R, Delgado-Bolton R, Oyen WJ, et al. FDG PET/CT: EANM procedure guidelines for tumour imaging: version 2.0.Eur J Nucl Med Mol Imaging · 2014 · 42(2):328-54doi:10.1007/s00259-014-2961-x · PMID 25452219

   The European procedure guideline (full text read): fasting, glucose, 60-minute uptake, SUV and SUL definitions, half-life and dose; a consensus guideline, not outcome evidence. PubMed dates the record 2014; its print issue, 42(2), belongs to 2015.

4. 4
   Fowler JS, Ido T. Initial and subsequent approach for the synthesis of 18FDG.Semin Nucl Med · 2002 · 32(1):6-12doi:10.1053/snuc.2002.29270 · PMID 11839070

   A retrospective by two of the chemists involved, dating FDG's development to 1976 and tracing the move from fluorine gas to nucleophilic synthesis and regional distribution; a historical review by participants, not an independent history.

5. 5
   Ido T, Wan CN, Casella V, Fowler JS, Wolf AP, Reivich M, Kuhl DE. Labeled 2-deoxy-D-glucose analogs. 18F-labeled 2-deoxy-2-fluoro-D-glucose, 2-deoxy-2-fluoro-D-mannose and 14C-2-deoxy-2-fluoro-D-glucose.J Labelled Compd Radiopharm · 1978 · 14(2):175-183doi:10.1002/jlcr.2580140204

   The original synthesis paper, not indexed in PubMed; cited for its date and authorship, which later papers citing it confirm. Its DOI could not be resolved from this workstation and should be confirmed at the publisher before publication.

6. 6
   Reivich M, Kuhl D, Wolf A, et al. The [18F]fluorodeoxyglucose method for the measurement of local cerebral glucose utilization in man.Circ Res · 1979 · 44(1):127-37doi:10.1161/01.res.44.1.127 · PMID 363301

   First published FDG measurement of regional brain glucose use in people, in two normal volunteers.

7. 7
   Phelps ME, Huang SC, Hoffman EJ, et al. Tomographic measurement of local cerebral glucose metabolic rate in humans with (F-18)2-fluoro-2-deoxy-D-glucose: validation of method.Ann Neurol · 1979 · 6(5):371-88doi:10.1002/ana.410060502 · PMID 117743

   Validates the human FDG model as an extension of Sokoloff's, and finds dephosphorylation of FDG-6-phosphate small but significant; brain only.

8. 8
   Beyer T, Townsend DW, Brun T, et al. A combined PET/CT scanner for clinical oncology.J Nucl Med · 2000 · 41(8):1369-79PMID 10945530

   First description of a combined PET/CT in one gantry, with more than 110 patients imaged; a technical report, not an accuracy study.

9. 9
   Deppen SA, Blume JD, Kensinger CD, et al. Accuracy of FDG-PET to diagnose lung cancer in areas with infectious lung disease: a meta-analysis.JAMA · 2014 · 312(12):1227-36doi:10.1001/jama.2014.11488 · PMID 25247519

   70 studies, 8,511 nodules: specificity 61% in regions with endemic infectious lung disease against 77% elsewhere, with very high heterogeneity; about lung infection generally, not parasites.

10. 10
    Kratzer W, Steinkellner S, Skotnik D, et al. Diagnosis of hepatic alveolar echinococcosis: 18F-FDG-PET activity compared to the Echinococcus multilocularis Ulm Ultrasound Classification.Nuklearmedizin · 2025 · 65(1):4-12doi:10.1055/a-2744-4139 · PMID 41326002

    German national database, 121 patients: mean SUVmax 6.0 (2.4 to 18.0) by ultrasound pattern, with SUVmax described as an indirect marker of inflammatory activity; retrospective. PubMed dates the record 2025; its print issue, 65(1), belongs to 2026.

11. 11
    Jiang L, Tong H, Tan H, et al. Intestinal pork tapeworm disease mimicking lymphoma on PET/CT imaging.Clin Nucl Med · 2014 · 39(9):842-4doi:10.1097/RLU.0000000000000505 · PMID 24999686

    A 17-year-old with multifocal FDG uptake read as possible lymphoma; pathology showed cysticercosis. One case; a comment letter on it followed in print.

12. 12
    Ye S, Wang WL, Zhao K. F-18 FDG hypermetabolism in mass-forming focal pancreatitis and old hepatic schistosomiasis with granulomatous inflammation misdiagnosed by PET/CT imaging.Int J Clin Exp Pathol · 2014 · 7(9):6339-44PMID 25337288

    A patient operated on for presumed metastatic pancreatic cancer had chronic pancreatitis and old hepatic schistosomiasis with granulomas; one case, no DOI in the record.

13. 13
    Akbulut S, Ozdemir E, Samdanci E, et al. Fascioliasis presenting as colon cancer liver metastasis on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography: A case report.World J Hepatol · 2019 · 11(8):656-662doi:10.4254/wjh.v11.i8.656 · PMID 31528248

    A colon cancer patient given 12 courses of chemotherapy for FDG-avid 'liver metastases' that were Fasciola at hepatectomy; one case.

14. 14
    Son P, Chen FY, Benedick JEC, et al. Clonorchiasis misdiagnosed as hepatic space-occupying lesion: a case report.Diagn Microbiol Infect Dis · 2025 · 113(4):117027doi:10.1016/j.diagmicrobio.2025.117027 · PMID 40773796

    Clonorchiasis with raised CA19-9 and FDG-avid liver and node lesions first diagnosed as cholangiocarcinoma; one case.

15. 15
    Ivanova K, Glatz K, Zippelius A, et al. Acute toxoplasmosis mimicking melanoma metastases: review of conditions causing false-positive results on ¹⁸F-FDG PET/CT.Dermatology · 2013 · 225(4):349-53doi:10.1159/000346333 · PMID 23406996

    A melanoma patient whose FDG-avid neck nodes were toxoplasma lymphadenitis; one case with a review, no SUV values in the abstract. PubMed dates the record 2013; its print issue, 225(4), belongs to 2012.

16. 16
    Cavailloles FA, Mure A, Nasser H, et al. Multiple liver amoebic abscesses detected on FDG PET/CT.Clin Nucl Med · 2014 · 39(1):79-80doi:10.1097/RLU.0b013e31828e98ad · PMID 23640216

    Amebic abscesses referred as liver metastases showed cold centers with faint rims, and the atypical pattern prompted biopsy; one case.

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    Comba C, Erdogan SV, Buyukasik S, et al. Strongyloides stercoralis infestation mimicking recurrence of ovarian cancer in the liver.J Obstet Gynaecol Res · 2022 · 48(11):2979-2981doi:10.1111/jog.15404 · PMID 36002883

    Liver masses on PET/CT read as ovarian cancer recurrence were Strongyloides at surgery; one case.

18. 18
    Moore W, Franceschi D. PET findings in pulmonary dirofilariasis.J Thorac Imaging · 2005 · 20(4):305-6doi:10.1097/01.rti.0000181524.95015.ea · PMID 16282912

    A hypermetabolic pulmonary round infarct caused by dirofilariasis; one case.

19. 19
    Watanabe S, Nakamura Y, Kariatsumari K, et al. Pulmonary paragonimiasis mimicking lung cancer on FDG-PET imaging.Anticancer Res · 2003 · 23(4):3437-40PMID 12926086

    The first reported lung fluke infection mimicking lung cancer on FDG-PET, resolved by shrinkage on repeat CT and eggs in sputum; one case, no DOI.

20. 20
    Pinnegar HP, Sánchez-Montalvá A, Barios Profitos M, Bosch-Nicolau P, Salvador F, Molina I. Utility of Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Patients with Visceral Leishmaniasis: Case Report and Literature Review.Am J Trop Med Hyg · 2021 · 104(3):934-944doi:10.4269/ajtmh.19-0858 · PMID 33534763

    Four local cases and a systematic review of 50 published cases; splenic uptake in 43 of 50; counts reports, not a diagnostic accuracy study.

21. 21
    Hillner BE, Siegel BA, Liu D, et al. Impact of positron emission tomography/computed tomography and positron emission tomography (PET) alone on expected management of patients with cancer: initial results from the National Oncologic PET Registry.J Clin Oncol · 2008 · 26(13):2155-61doi:10.1200/JCO.2007.14.5631 · PMID 18362365

    22,975 Medicare-covered studies: physicians changed intended management in 36.5%; measures intended plans, not patient outcomes.

22. 22
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    Summary of the Lugano recommendations: PET/CT for staging FDG-avid lymphomas and a 5-point response scale; a consensus summary by one author.

23. 23
    Kubota R, Yamada S, Kubota K, et al. Intratumoral distribution of fluorine-18-fluorodeoxyglucose in vivo: high accumulation in macrophages and granulation tissues studied by microautoradiography.J Nucl Med · 1992 · 33(11):1972-80PMID 1432158

    In one transplanted mouse tumor, macrophages and granulation tissue held more FDG than cancer cells and up to 29% of glucose use was non-tumor; the 29% is a maximum in that model, not a figure for human tumors.

24. 24
    Kinouchi T, Morishima Y, Uyama S, et al. Neurocysticercosis in a Japanese woman with lung cancer who repeatedly visited endemic countries.BMC Infect Dis · 2021 · 21(1):1077doi:10.1186/s12879-021-06778-1 · PMID 34663259

    Cold brain lesions on PET in a lung cancer patient were treated as neurocysticercosis with negative serology and DNA tests; the one resected lesion was a metastasis. One case.

25. 25
    Liu C, Xu W, Liu P, Wei Y. A Mistaken Diagnosis of Secondary Glioblastoma as Parasitosis.Front Neurol · 2019 · 10:952doi:10.3389/fneur.2019.00952 · PMID 31555204

    A glioblastoma treated as parasitosis, partly because of low glucose metabolism on FDG-PET, until surgery seven years after onset; one case.

26. 26
    Chang JM, Lee HJ, Goo JM, et al. False positive and false negative FDG-PET scans in various thoracic diseases.Korean J Radiol · 2006 · 7(1):57-69doi:10.3348/kjr.2006.7.1.57 · PMID 16549957

    Pictorial review stating that FDG is not cancer-specific and listing the infections that read hot and the low-glycolysis tumors that read cold; illustrative, gives no accuracy figures.

27. 27
    Eskian M, Alavi A, Khorasanizadeh M, et al. Effect of blood glucose level on standardized uptake value (SUV) in ¹⁸F- FDG PET-scan: a systematic review and meta-analysis of 20,807 individual SUV measurements.Eur J Nucl Med Mol Imaging · 2018 · 46(1):224-237doi:10.1007/s00259-018-4194-x · PMID 30350009

    Pooled individual data from 29 studies and 8,380 patients: tumor SUV fell significantly only above 200 mg/dL; SUV, not diagnostic accuracy, was the outcome. PubMed dates the record 2018; its print issue, 46(1), belongs to 2019.

28. 28
    Lewitschnig S, Gedela K, Toby M, et al. ¹⁸F-FDG PET/CT in HIV-related central nervous system pathology.Eur J Nucl Med Mol Imaging · 2013 · 40(9):1420-7doi:10.1007/s00259-013-2448-1 · PMID 23685752

    In 29 HIV-positive patients, toxoplasmosis read below cortex and brain lymphoma far above it; retrospective, 11 and 5 patients in the key groups.

29. 29
    Jolepalem P, Wong CY. Neurocysticercosis on 18F-FDG PET/MRI: co-registered Images.Clin Nucl Med · 2014 · 39(1):e110-3doi:10.1097/RLU.0b013e3182817ad8 · PMID 23579982

    A ring-enhancing temporal lesion suspected to be a brain tumor; FDG-PET excluded malignancy and supported neurocysticercosis. One case.

30. 30
    Reuter S, Grüner B, Buck AK, et al. Long-term follow-up of metabolic activity in human alveolar echinococcosis using FDG-PET.Nuklearmedizin · 2008 · 47(4):147-52PMID 18690373

    Fifteen patients followed a median 6.5 years: metabolically inactive lesions reactivated, and lack of activity was not equivalent to parasite death; small, no DOI in the record.

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    Review of why tumors accumulate FDG (transporters, hexokinase, hypoxia) that also states uptake is relatively nonspecific; a narrative review.

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    Purandare NC, Pramesh CS, Agarwal JP, et al. Solitary pulmonary nodule evaluation in regions endemic for infectious diseases: Do regional variations impact the effectiveness of fluorodeoxyglucose positron emission tomography/computed tomography.Indian J Cancer · 2017 · 54(1):271-275doi:10.4103/0019-509X.219563 · PMID 29199704

    191 Indian patients: tuberculous nodules overlapped cancers in SUVmax (up to 22.5) and specificity at SUVmax 2.5 was 34.7%; one tertiary center.

33. 33
    Yoldaş B, Gürsoy S, Budak E, et al. FDG PET/CT signs of proven pulmonary hydatid cyst: is there any clue?Jpn J Radiol · 2022 · 40(11):1194-1200doi:10.1007/s11604-022-01296-9 · PMID 35727457

    Seventeen proven pulmonary hydatid cysts: SUVmax 0.5 to 15.8 and a doughnut sign in 10; retrospective, small.

34. 34
    Cypess AM, Lehman S, Williams G, et al. Identification and importance of brown adipose tissue in adult humans.N Engl J Med · 2009 · 360(15):1509-17doi:10.1056/NEJMoa0810780 · PMID 19357406

    Review of 3,640 FDG-PET/CT scans finding active brown fat in 7.5% of women and 3.1% of men; establishes a normal cause of uptake, not a disease.

35. 35
    Hamidizadeh R, Eftekhari A, Wiley EA, et al. Metformin Discontinuation prior to FDG PET/CT: A Randomized Controlled Study to Compare 24- and 48-hour Bowel Activity.Radiology · 2018 · 289(2):418-425doi:10.1148/radiol.2018180078 · PMID 30106348

    Randomized trial in 90 patients: stopping metformin for 48 hours lowered bowel uptake but raised exam-day glucose; measures uptake, not diagnostic accuracy.

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    Rat abscess model naming the FDG-avid cells: young fibroblasts, endothelium, neutrophils and macrophages; animal data.

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    Koppenol WH, Bounds PL, Dang CV. Otto Warburg's contributions to current concepts of cancer metabolism.Nat Rev Cancer · 2011 · 11(5):325-37doi:10.1038/nrc3038 · PMID 21508971

    Historical review restating Warburg's roughly tenfold aerobic lactate finding and correcting the belief that it reflects damaged respiration; a review, not new data.

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    Shows that yeast hexokinase accepts 2-deoxy-2-fluoro-D-glucose as a good substrate while most other changes at carbon 2 abolish binding; an enzyme study, not an imaging study.

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    Yang L, Maldjian PD, Peters S. FDG PET/CT findings of a ruptured pulmonary hydatid cyst with histopathological correlation.Clin Imaging · 2013 · 37(4):798-801doi:10.1016/j.clinimag.2012.12.007 · PMID 23462730

    One patient, suspected of lung cancer: the cyst was metabolically absent and the surrounding consolidation hypermetabolic, with histological correlation; a single case.

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    Caoduro C, Porot C, Vuitton DA, et al. The role of delayed 18F-FDG PET imaging in the follow-up of patients with alveolar echinococcosis.J Nucl Med · 2013 · 54(3):358-63doi:10.2967/jnumed.112.109942 · PMID 23303963

    In 120 scans of 70 treated patients, 3-hour imaging changed the reading in 32.5% and showed perilesional uptake; supports, without proving, safe treatment interruption when delayed PET and serology are both negative.

41. 41
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    Five head and neck cancer patients scanned fasting and after glucose loading; tumor SUV fell significantly. Very small, and the abstract misprints the isotope as [11F].

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    The rat-brain deoxyglucose method that FDG imaging was built to translate into people; the PubMed record has no abstract, so it is cited here for the method's existence, date and subject only.

43. 43
    Ter-Pogossian MM, Phelps ME, Hoffman EJ, Mullani NA. A positron-emission transaxial tomograph for nuclear imaging (PETT).Radiology · 1975 · 114(1):89-98doi:10.1148/114.1.89 · PMID 1208874

    Describes the PETT, a hexagon of 24 sodium iodide detectors in coincidence that imaged positron emitters in phantoms and animals; it predates FDG and imaged no patients.

44. 44
    Som P, Atkins HL, Bandoypadhyay D, et al. A fluorinated glucose analog, 2-fluoro-2-deoxy-D-glucose (F-18): nontoxic tracer for rapid tumor detection.J Nucl Med · 1980 · 21(7):670-5PMID 7391842

    Rapid FDG uptake in transplanted and spontaneous animal tumors and no toxicity at high multiples of the human dose; animal data only.

45. 45
    Di Chiro G, DeLaPaz RL, Brooks RA, et al. Glucose utilization of cerebral gliomas measured by [18F] fluorodeoxyglucose and positron emission tomography.Neurology · 1982 · 32(12):1323-9doi:10.1212/wnl.32.12.1323 · PMID 6983044

    In 23 patients, glucose use was higher in high-grade than low-grade gliomas; an early human oncology series, small and from one center.

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    The nucleophilic synthesis that made FDG production efficient, up to 50% yield in about 50 minutes; chemistry, not clinical evidence.

47. 47
    Sathekge MM, Maes A, Pottel H, et al. Dual time-point FDG PET-CT for differentiating benign from malignant solitary pulmonary nodules in a TB endemic area.S Afr Med J · 2010 · 100(9):598-601doi:10.7196/samj.4082 · PMID 20822650

    In 30 South African nodules, tuberculomas matched cancers on SUVmax and on change between time points; small single-center study.

48. 48
    Phelps ME, Hoffman EJ, Mullani NA, Ter-Pogossian MM. Application of annihilation coincidence detection to transaxial reconstruction tomography.J Nucl Med · 1975 · 16(3):210-24PMID 1113170

    The companion technical paper evaluating annihilation coincidence detection in the prototype scanner; phantom and animal work only, and the record carries no DOI.

49. 49
    Gallagher BM, Ansari A, Atkins H, et al. Radiopharmaceuticals XXVII. 18F-labeled 2-deoxy-2-fluoro-d-glucose as a radiopharmaceutical for measuring regional myocardial glucose metabolism in vivo: tissue distribution and imaging studies in animals.J Nucl Med · 1977 · 18(10):990-6PMID 903484

    Mouse and dog biodistribution: FDG retained in heart and brain while clearing from liver, lung, kidney and blood; animal data, no DOI in the record.

50. 50
    Gallagher BM, Fowler JS, Gutterson NI, et al. Metabolic trapping as a principle of oradiopharmaceutical design: some factors resposible for the biodistribution of [18F] 2-deoxy-2-fluoro-D-glucose.J Nucl Med · 1978 · 19(10):1154-61PMID 214528

    The paper that named metabolic trapping; the record has no abstract and no DOI, and the title's two typing errors ('oradiopharmaceutical', 'resposible') are reproduced exactly as PubMed holds them.

51. 51
    Patronas NJ, Di Chiro G, Brooks RA, et al. Work in progress: [18F] fluorodeoxyglucose and positron emission tomography in the evaluation of radiation necrosis of the brain.Radiology · 1982 · 144(4):885-9doi:10.1148/radiology.144.4.6981123 · PMID 6981123

    Five patients: radiation necrosis read low and recurrent glioma read high, all confirmed by biopsy or autopsy; too small to estimate accuracy.

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    Keyes JW. SUV: standard uptake or silly useless value?J Nucl Med · 1995 · 36(10):1836-9PMID 7562051

    An editorial questioning the SUV; the record has no abstract or DOI, so only its title and date are relied on here.

53. 53
    Gould MK, Maclean CC, Kuschner WG, et al. Accuracy of positron emission tomography for diagnosis of pulmonary nodules and mass lesions: a meta-analysis.JAMA · 2001 · 285(7):914-24doi:10.1001/jama.285.7.914 · PMID 11180735

    Meta-analysis of 40 studies and 1,474 lung lesions; study quality was rated only fair and few data existed for nodules under 1 cm.

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    Retrospective review of the first 359 PET/CT studies in 347 patients; 14 (4.0%) had uptake in fat with no node or muscle correlate; the record carries no DOI.

55. 55
    Wahl RL, Jacene H, Kasamon Y, Lodge MA. From RECIST to PERCIST: Evolving Considerations for PET response criteria in solid tumors.J Nucl Med · 2009 · 50 Suppl 1:122S-50Sdoi:10.2967/jnumed.108.057307 · PMID 19403881

    Proposes PERCIST 1.0, including the 30% SUV decline for response and a liver reference region; a proposal based on literature review, not a validation study.

56. 56
    Badawi RD, Shi H, Hu P, et al. First Human Imaging Studies with the EXPLORER Total-Body PET Scanner.J Nucl Med · 2019 · 60(3):299-303doi:10.2967/jnumed.119.226498 · PMID 30733314

    First human images from a 194-cm total-body scanner; case studies, not a controlled trial, and five authors list affiliations with United Imaging Healthcare, a scanner manufacturer.

57. 57
    Kratochwil C, Flechsig P, Lindner T, et al. ⁶⁸Ga-FAPI PET/CT: Tracer Uptake in 28 Different Kinds of Cancer.J Nucl Med · 2019 · 60(6):801-805doi:10.2967/jnumed.119.227967 · PMID 30954939

    Retrospective quantification of FAPI uptake in 80 patients with 28 tumor types; describes uptake, not diagnostic accuracy against FDG.

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    Hofman MS, Lawrentschuk N, Francis RJ, et al. Prostate-specific membrane antigen PET-CT in patients with high-risk prostate cancer before curative-intent surgery or radiotherapy (proPSMA): a prospective, randomised, multicentre study.Lancet · 2020 · 395(10231):1208-1216doi:10.1016/S0140-6736(20)30314-7 · PMID 32209449

    Randomized trial in 302 men: PSMA PET/CT 92% accurate against 65% for conventional imaging; funded by Movember and the Prostate Cancer Foundation of Australia. About prostate cancer staging only.

59. 59
    Salvador F, Escolà-Vergé L, Barios M, et al. Usefulness of the FDG PET/CT in the management of cystic echinococcosis: A pilot study.Acta Trop · 2021 · 227:106295doi:10.1016/j.actatropica.2021.106295 · PMID 34954257

    Prospective pilot of 16 patients with hydatid cysts, all at transitional or inactive stages (CE3 to CE5): no correlation between FDG uptake and cyst viability; small, and it drew a published comment from the WHO collaborating center.

60. 60
    Manciulli T, Tamarozzi F, D'Alessandro GL, Gruener B, Brunetti E. Comment on "Usefulness of the FDG PET/CT in the management of cystic echinococcosis: A pilot study".Acta Trop · 2022 · 238:106775doi:10.1016/j.actatropica.2022.106775 · PMID 36462531

    A letter from the Pavia group that serves as the WHO collaborating center for cystic echinococcosis and the Ulm group; it has no abstract in PubMed, so only the fact of the published comment is relied on, not its argument.

61. 61
    Bentestuen M, Al-Obaydi N, Zacho HD. FAPI-avid nonmalignant PET/CT findings: An expedited systematic review.Semin Nucl Med · 2023 · 53(5):694-705doi:10.1053/j.semnuclmed.2023.02.001 · PMID 36813670

    Systematic review counting 2,372 nonmalignant FAPI-avid findings in 108 studies, 74% of them case reports; counts reports, not rates.

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    Peters L, Jiang W, Eberhardt N, Hagemann JB, Grüner B, Tappe D. FDG-PET/CT-Scans and Biomarker Levels Predicting Clinical Outcome in Patients with Alveolar Echinococcosis-A Single-Center Cohort Study with 179 Patients.Pathogens · 2023 · 12(8):1041doi:10.3390/pathogens12081041 · PMID 37624001

    Retrospective single-center cohort; in multivariate analysis the PET/CT result was the strongest predictor of outcome (odds ratio 8.908, 95% confidence interval 3.019 to 26.285).

63. 63
    Husmann L, Sah BR, Kotasidis F, et al. Whole-body dynamic FDG-PET/CT parametric imaging in alveolar echinococcosis.Ann Nucl Med · 2025 · 40(2):154-161doi:10.1007/s12149-025-02113-9 · PMID 41051686

    Patlak imaging in 20 data sets roughly doubled lesion-to-liver contrast, and ratios tracked antibody levels; one author is affiliated with GE Healthcare, which sells this technology. PubMed dates the record 2025; its print issue, 40(2), belongs to 2026.

64. 64
    Simon G, Grenouillet F, Richou C, et al. Correlation between imaging features and rEm18 antibodies in alveolar echinococcosis: results from a multicenter study in France.Parasite · 2025 · 32:8doi:10.1051/parasite/2024076 · PMID 39918234

    Retrospective analysis of the prospective EchinoVISTA cohort (NCT02876146), 45 patients; SUVmax 5.1 (interquartile range 4.4 to 6.2) against 2.6 (2.4 to 3.9) by antibody index.

65. 65
    Calame P, Richou C, Blagosklonov O, et al. Is a shortened postoperative albendazole duration after curative surgery for alveolar echinococcosis possible? Results from a prospective multicenter study.Parasit Vectors · 2025 · 18(1):465doi:10.1186/s13071-025-07095-1 · PMID 41250088

    Prospective multicenter study of 15 patients; small, and the antibody-index analysis was retrospective.

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    Gupta N, Choudhury PS, Rana A. ⁶⁸Ga-FAPI PET/CT in diagnosis, staging and management of gastric carcinoma: A systematic review and meta-analysis.Asia Ocean J Nucl Med Biol · 2026 · 14(2):135-150doi:10.22038/aojnmb.2026.93248.1690 · PMID 42558995

    Fourteen studies, 661 patients: FAPI outperformed FDG head to head in gastric cancer, with possible small-study effects; the authors recommend it as a complement, not a stand-alone test.

67. 67
    Torizuka T, Tamaki N, Inokuma T, et al. In vivo assessment of glucose metabolism in hepatocellular carcinoma with FDG-PET.J Nucl Med · 1995 · 36(10):1811-7PMID 7562048

    In 17 hepatocellular carcinomas, uptake tracked hexokinase and grade, and glucose-6-phosphatase reduced retention in some tumors; a small single-center series.

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    Godinez F, Mingels C, Bayerlein R, Mehadji B, Nardo L. Total Body PET/CT: Future Aspects.Semin Nucl Med · 2024 · 55(1):107-115doi:10.1053/j.semnuclmed.2024.10.011 · PMID 39542814

    Narrative review from the EXPLORER group at UC Davis; states that the first total-body PET/CT was cleared by the United States Food and Drug Administration in 2019 at UC Davis and that over 50 long-axial scanners are in use. PubMed dates the record 2024; its print issue, 55(1), belongs to 2025.

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    Shankar LK, Huang E, Litiere S, et al. Meta-Analysis of the Test-Retest Repeatability of [18F]-Fluorodeoxyglucose Standardized Uptake Values: Implications for Assessment of Tumor Response.Clin Cancer Res · 2023 · 29(1):143-153doi:10.1158/1078-0432.CCR-21-3143 · PMID 36302172

    Extension of the 2012 de Langen meta-analysis; 11 studies; repeatability improves with higher uptake and varies with lesion site.

70. 70
    Tavakoli S, Zamora D, Ullevig S, Asmis R. Bioenergetic profiles diverge during macrophage polarization: implications for the interpretation of 18F-FDG PET imaging of atherosclerosis.J Nucl Med · 2013 · 54(9):1661-7doi:10.2967/jnumed.112.119099 · PMID 23886729

    In cultured mouse macrophages, only LPS stimulation raised glucose uptake; M1 and M2 polarization did not. Cell culture, not imaging of lesions.

71. 71
    Zhang T, Zhang Y, Yang Z, et al. [Echinococcus multilocularis] protoscoleces enhance glycolysis to promote M2 Macrophages through PI3K/Akt/mTOR Signaling Pathway.Pathog Glob Health · 2022 · 117(4):409-416doi:10.1080/20477724.2022.2104055 · PMID 35876088

    Tapeworm protoscoleces pushed macrophages toward M2 with raised glycolytic enzymes; in vitro. PubMed's plain-text title drops the species name, restored here in brackets. PubMed dates the record 2022; its print issue, 117(4), belongs to 2023.

72. 72
    Sahlmann CO, Siefker U, Lehmann K, Meller J. Dual time point 2-[18F]fluoro-2'-deoxyglucose positron emission tomography in chronic bacterial osteomyelitis.Nucl Med Commun · 2004 · 25(8):819-23doi:10.1097/01.mnm.0000135600.23896.9d · PMID 15266177

    Dual-time-point imaging separated bacterial osteomyelitis from bone malignancy, except in the one patient with foreign-body granulomas; 17 plus 4 patients.

73. 73
    Stone M, Dalal I, Stone C, Dalal B. 18-FDG Uptake in Pulmonary Dirofilariasis.J Radiol Case Rep · 2015 · 9(4):28-33doi:10.3941/jrcr.v9i4.1869 · PMID 26622926

    A smoker's 13 mm nodule with mild uptake was resected and held a dead heartworm in a granuloma; one case, no SUV given.

74. 74
    Losada H, Hirsch M, Guzmán P, et al. Fascioliasis simulating an intrahepatic cholangiocarcinoma-Case report with imaging and pathology correlation.Hepatobiliary Surg Nutr · 2015 · 4(1):E1-7doi:10.3978/j.issn.2304-3881.2014.09.15 · PMID 25713810

    A liver lesion studied with CT, MRI and PET/CT and resected as intrahepatic cholangiocarcinoma proved to be granulomatous inflammation around Fasciola eggs; one case, uptake values not given in the abstract.

75. 75
    Adin ME, Nguyen D, Shin C, Pucar D. COVID-19 vaccine-associated reactive axillary lymph nodes on FDG PET/CT: a systematic review and meta-analysis.Nucl Med Commun · 2025 · 46(12):1232-1239doi:10.1097/MNM.0000000000002041 · PMID 40900040

    25 studies, 5,010 subjects; prevalence 38.6% ± 17.6, mean SUVmax 2.8 ± 1.2; measures uptake, not diagnostic error rates.

76. 76
    Karlsen W, Akily L, Mierzejewska M, et al. Is 18F-FDG-PET/CT an Optimal Imaging Modality for Detecting Immune-Related Adverse Events after Immune-Checkpoint Inhibitor Therapy? Pros and Cons.Cancers (Basel) · 2024 · 16(11):1990doi:10.3390/cancers16111990 · PMID 38893111

    Narrative review of the metabolic patterns of immune-related adverse events and of pseudoprogression.

77. 77
    Casali M, Lauri C, Altini C, et al. State of the art of ¹⁸F-FDG PET/CT application in inflammation and infection: a guide for image acquisition and interpretation.Clin Transl Imaging · 2021 · 9(4):299-339doi:10.1007/s40336-021-00445-w · PMID 34277510

    Italian consensus summarizing 291 papers on deliberate FDG imaging of infection and inflammation, and noting the lack of standardization in that field.

78. 78
    Salem N, Balkman JD, Wang J, et al. In vivo imaging of schistosomes to assess disease burden using positron emission tomography (PET).PLoS Negl Trop Dis · 2010 · 4(9)doi:10.1371/journal.pntd.0000827 · PMID 20877718

    Live Schistosoma mansoni take up FDG in vitro, and in athymic mice portal FDG tracked worm burden; immunodeficient mice, and the praziquantel effect was not significant.

79. 79
    Kashiide T, Kikuta S, Yamaguchi M, et al. Molecular and functional characterization of glucose transporter genes of the fox tapeworm Echinococcus multilocularis.Mol Biochem Parasitol · 2018 · 225:7-14doi:10.1016/j.molbiopara.2018.08.004 · PMID 30130566

    The tapeworm transporter EmGLUT1 carries 2-deoxyglucose in frog oocytes and is expressed at every life stage; it does not test fluorine-18 FDG or imaging.

80. 80
    Lindner T, Stenzel J, Koslowski N, et al. Anatomical MRI and [¹⁸F]FDG PET/CT imaging of Schistosoma mansoni in a NMRI mouse model.Sci Rep · 2020 · 10(1):17343doi:10.1038/s41598-020-74226-2 · PMID 33060721

    In immunocompetent mice, FDG-PET/CT could not grade schistosome infection; only splenic uptake differed. Animal data.

81. 81
    Galán-Puchades MT, Fuentes MV. On Taeniasis/Cysticercosis Mimicking Lymphoma on PET/CT Imaging.Clin Nucl Med · 2015 · 40(7):614doi:10.1097/RLU.0000000000000671 · PMID 25899585

    A letter commenting on the Jiang case; it has no abstract in PubMed, so only its existence and title are reported here, not its argument.

82. 82
    Takenaka J, Hirata K, Watanabe S, Takahata M, Kudo K. Bone Echinococcosis Mimicking Malignancy on FDG PET.Clin Nucl Med · 2023 · 48(11):e523-e525doi:10.1097/RLU.0000000000004838 · PMID 37793180

    One case; a mass across the second to fifth thoracic vertebrae with rim SUVmax 10.6; alveolar echinococcosis confirmed immunologically.

83. 83
    Eberhardt N, Haggenmüller B. Sectional Imaging for Alveolar Echinococcosis.Visc Med · 2025 · 41(6):320-327doi:10.1159/000548686 · PMID 41376838

    203 patients at Ulm, 2019 to 2023; in the 89 with both PET and MRI, PET activity in over 90% of Kodama type 2 and 3 lesions and none in type 5; retrospective, one specialist center.

84. 84
    Joseph SE, Makawi KS, Joseph P, Alsuwaidi HN. Disseminated Pulmonary and Hepatic Cystic Echinococcosis Presenting as Suspected Pulmonary Embolism and Mimicking Metastatic Malignancy.Cureus · 2026 · 18(8):e115184doi:10.7759/cureus.115184 · PMID 42798686

    One case, a 27-year-old; serology 1:640; diagnosis without histology.

85. 85
    Altinyay ME, Alharthi A, Alassiri AH, Syed GM. 18F-FDG Hypermetabolism in Spinal Cord Schistosomiasis.Clin Nucl Med · 2016 · 41(3):211-3doi:10.1097/RLU.0000000000001003 · PMID 26447373

    A prominently hypermetabolic spinal cord lesion spanning the sixth to ninth thoracic vertebrae that proved to contain Schistosoma mansoni eggs at biopsy; one case.

86. 86
    Lesmana CRA, Adiwinata R, Simca J, et al. Case Report: Pancreatic toxoplasmosis: role of endoscopic ultrasound in diagnosis.Front Gastroenterol (Lausanne) · 2026 · 5:1763923doi:10.3389/fgstr.2026.1763923 · PMID 42326016

    One case; biopsy showed chronic inflammation without malignancy; toxoplasmosis diagnosed with concurrent encephalitis.

87. 87
    Shah K, Prabhash K, Noronha V, et al. A diagnostic dilemma in a patient with lymphoma.Indian J Med Paediatr Oncol · 2013 · 34(2):114-6doi:10.4103/0971-5851.116197 · PMID 24049301

    Gastric wall thickening and lymphadenopathy on CT and PET after lymphoma treatment were Strongyloides at biopsy; one case.

88. 88
    Dai J, Wang H, Wang H, Tian R. Subtly Increased Focal FDG Activity in the Liver Due to Paragonimiasis.Clin Nucl Med · 2023 · 48(8):e407-e409doi:10.1097/RLU.0000000000004736 · PMID 37290448

    One case; biopsy showed Paragonimus westermani.

89. 89
    Kimura-Hayama ET, Higuera JA, Corona-Cedillo R, et al. Neurocysticercosis: radiologic-pathologic correlation.Radiographics · 2010 · 30(6):1705-19doi:10.1148/rg.306105522 · PMID 21071384

    Radiology review of neurocysticercosis, the most common cause of acquired epilepsy in endemic settings; about CT and MRI, not FDG.

90. 90
    Nguyen J, Puthillath A. Coexistence of Lung Cancer and Neurocysticercosis: A Rare Case.Cureus · 2024 · 16(4):e58456doi:10.7759/cureus.58456 · PMID 38765376

    One case; the PET findings concerned the lung and lymph nodes, not the brain lesion.

91. 91
    Mirgh SP, Shah VD, Sorabjee JS. A Microbial Old Friend with a New Face: A Rare Case of Pyrexia of Unknown Origin and Leukemoid Reaction.J Glob Infect Dis · 2017 · 9(3):117-119doi:10.4103/jgid.jgid_166_16 · PMID 28878524

    Disseminated cysticercosis presenting as fever of unknown origin with generalized muscle uptake on PET/CT; one case.

92. 92
    Savigamin C, Benjacholamas V, Sriprasart T. Pulmonary cysticercosis: A case report of abnormal lung nodule based on chest computerized tomography.Respir Med Case Rep · 2022 · 40:101764doi:10.1016/j.rmcr.2022.101764 · PMID 36386281

    A pulmonary cysticercosis nodule that was not FDG-avid but was biopsied because it grew slowly; one case.

93. 93
    Chung JK, Kim YK, Kim SK, et al. Usefulness of 11C-methionine PET in the evaluation of brain lesions that are hypo- or isometabolic on 18F-FDG PET.Eur J Nucl Med Mol Imaging · 2002 · 29(2):176-82doi:10.1007/s00259-001-0690-4 · PMID 11926379

    Methionine PET was raised in 31 of 35 FDG-cold brain tumors and not in 10 benign lesions, three of them cysticercosis; one Korean center, small benign group.

94. 94
    Vadi SK, Kumar R, Singh H, et al. 68Ga-Prostate-Specific Membrane Antigen Expression in Neurocysticercosis Lesions in a Patient With Prostate Carcinoma.Clin Nucl Med · 2018 · 43(4):e122-e124doi:10.1097/RLU.0000000000001990 · PMID 29401150

    PSMA tracer uptake in the walls of neurocysticercosis cysts; one case, mechanism (angiogenesis) proposed, not shown.

95. 95
    Brumpt E, Blagosklonov O, Calame P, et al. AE hepatic lesions: correlation between calcifications at CT and FDG-PET/CT metabolic activity.Infection · 2019 · 47(6):955-960doi:10.1007/s15010-019-01328-z · PMID 31165442

    In 61 patients at Besançon, 93% of alveolar echinococcosis liver lesions were hypermetabolic, and activity went with microcalcification; association, single center.

96. 96
    Ayituhongman A, Qizhou Z, Yongde Q, et al. Application of 11C-CHO in the imaging of cerebral alveolar echinococcosis: A prospective study.Medicine (Baltimore) · 2025 · 104(21):e42191doi:10.1097/MD.0000000000042191 · PMID 40419893

    In 8 patients with 35 cerebral lesions, the carbon-11 choline tracer found all 35 and FDG 24; small, single center, no tumor comparison group. The abstract names the tracer 11C-acetylcholine (11C-CHO); this page calls it choline because 11C-choline is the established tracer that matches the abstract's description of its prior use in prostate, esophageal and lung cancer, but the paper's own wording differs.

97. 97
    Shen Z, Wang Y, Chen X, et al. Clinical value of the semi-quantitative parameters of ¹⁸F-fluorodeoxyglucose PET/CT in the classification of hepatic echinococcosis in the Qinghai Tibetan area of China.BMC Med Imaging · 2024 · 24(1):194doi:10.1186/s12880-024-01371-9 · PMID 39085759

    In 36 resected lesions from 20 patients, SUVmax separated alveolar from cystic echinococcosis; small, retrospective, and both groups were parasitic.

98. 98
    Zhou Z, Lv Y, Zheng D, et al. Cerebral Echinococcosis Mimicking Malignancy on 68 Ga-FAPI PET/MR.Clin Nucl Med · 2025 · 50(8):795-797doi:10.1097/RLU.0000000000005778 · PMID 39994890

    A suspected glioma with FAPI SUVmax 6.0 was a hydatid cyst at resection; one case.

99. 99
    Sun R, Liu L, Zeng G, Chen X. 18 F-FDG PET/CT findings in a patient with cerebral schistosomiasis mimicking the metastatic tumor.Asian J Surg · 2022 · 46(1):585-586doi:10.1016/j.asjsur.2022.06.183 · PMID 35842381

    A letter reporting cerebral schistosomiasis that mimicked a metastatic tumor on FDG-PET/CT; it has no abstract in PubMed, so only its title is relied on. PubMed dates the record 2022; its print issue, 46(1), belongs to 2023.

100. 100
     Daghigh A, Grüner JM, Mørup P. Intestinal FDG-PET/CT imaging of an Eritrean with schistosomiasis seen in Denmark.Eur J Hybrid Imaging · 2019 · 3(1):17doi:10.1186/s41824-019-0064-4 · PMID 34191162

     Avid abdominal nodes in a migrant with schistosomiasis; the authors state that PET/CT neither detects schistosomes nor diagnoses schistosomiasis. One case.

101. 101
     D'Sa L, Pezzuto F, Lunardi F, et al. A Complex Case of Pulmonary Silico-Tuberculosis and Review of Literature.Diagnostics (Basel) · 2023 · 13(17)doi:10.3390/diagnostics13172728 · PMID 37685266

     A man with schistosomiasis-associated bladder cancer whose hypermetabolic lung nodules, resected as suspected metastasis, were silicosis and tuberculosis; one case.

102. 102
     Bouvard V, Baan R, Straif K, et al. A review of human carcinogens--Part B: biological agents.Lancet Oncol · 2009 · 10(4):321-2doi:10.1016/s1470-2045(09)70096-8 · PMID 19350698

     The Lancet Oncology summary of IARC Monograph 100B, which placed Clonorchis sinensis and Opisthorchis viverrini in Group 1; the record has no abstract, so it is cited for the classification and its date.

103. 103
     Kosaka S, Shimizu S, Nakayamada S, et al. A delayed diagnosis of fascioliasis: The importance of appropriate fecal diagnostic method.J Infect Chemother · 2023 · 30(5):454-458doi:10.1016/j.jiac.2023.11.006 · PMID 37944698

     PET and a lymph node biopsy were done on suspicion of malignancy before Fasciola eggs were found with the right stool method; one case. PubMed dates the record 2023; its print issue, 30(5), belongs to 2024.

104. 104
     Schulz N, Herrán de la Gala D, Rozenblum L, et al. Radiological and FDG-PET imaging features of Epstein-Barr virus-positive primary central nervous system lymphomas.J Neurol · 2026 · 273(8)doi:10.1007/s00415-026-13974-z · PMID 42410107

     Multicenter retrospective series, 58 cases from 2008 to 2025; FDG hypermetabolic in 25 of 30 scanned.

105. 105
     Zhou W, Zhao J, Xing Y, et al. Diffuse hepatic amebiasis detected by FDG PET/CT.Clin Nucl Med · 2015 · 40(2):e167-70doi:10.1097/RLU.0000000000000605 · PMID 25275416

     Early hepatic amebiasis with diffuse heterogeneous liver uptake plus orbital and ear foci; one case.

106. 106
     Chandra P, Chakravarthy S, Jain D, Nath S. Hypermetabolic Diffuse Proximal Small Bowel Wall Thickening on Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography? Consider Strongyloidiasis among the Differentials.Indian J Nucl Med · 2018 · 33(4):368-369doi:10.4103/ijnm.IJNM_96_18 · PMID 30386068

     Hypermetabolic small-bowel wall thickening in a patient on high-dose steroids, diagnosed as strongyloidiasis at endoscopic biopsy; one image report.

107. 107
     Terasaka Y, Inaba H, Furuta S, et al. [Human pulmonary dirofilariasis].Kyobu Geka · 2011 · 64(12):1096-9PMID 22187872

     A 2.5 cm nodule with no FDG accumulation, judged benign, resected at the patient's choice and found to be dirofilariasis; one case, article in Japanese with an English abstract.

108. 108
     Travis WD, Brambilla E, Noguchi M, et al. International association for the study of lung cancer/american thoracic society/european respiratory society international multidisciplinary classification of lung adenocarcinoma.J Thorac Oncol · 2011 · 6(2):244-85doi:10.1097/JTO.0b013e318206a221 · PMID 21252716

     Consensus classification; states that the terms BAC and mixed subtype adenocarcinoma are no longer used.

109. 109
     Rosica D, Cheng SC, Hudson M, et al. Effects of hyperglycemia on fluorine-18-fluorodeoxyglucose biodistribution in a large oncology clinical practice.Nucl Med Commun · 2018 · 39(5):417-422doi:10.1097/MNM.0000000000000829 · PMID 29629997

     Notes guideline glucose cutoffs ranging from 120 to 200 mg/dL and finds mostly mild effects on biodistribution below 200 mg/dL; retrospective, one center.

110. 110
     Huang H, Altunay B, Schäfer L, et al. Diagnostic Efficacy of FAPI-PET/CT Versus [18F]FDG-PET/CT in Upper-Abdominal Malignancies: A Systematic Review and Meta-Analysis.Diagnostics (Basel) · 2026 · 16(4):520doi:10.3390/diagnostics16040520 · PMID 41750670

     31 studies, 1,377 participants; a relative-risk meta-analysis; sensitivity 98% against 79%, specificity 83% against 87%.

111. 111
     Msherghi A, Abuajamieh M, Ekreer M, et al. Comparative diagnostic performance of [68Ga]Ga-FAPI PET/CT and [18F]FDG PET/CT in biliary tract cancers: a systematic review and meta-analysis.Eur J Nucl Med Mol Imaging · 2025 · 52(11):4200-4212doi:10.1007/s00259-025-07264-5 · PMID 40214739

     Pooled odds ratio 4.87 (95% confidence interval 1.75 to 13.56) for primary tumor detection; moderate heterogeneity for metastases.

112. 112
     Wan QC, Bai L, Wang ZY, Ji B. Diagnostic Performance of FAPI PET/CT for the Detection of Lymph Node Metastases in Lung Cancer Patients: A Meta-analysis.Acad Radiol · 2024 · 32(5):3030-3038doi:10.1016/j.acra.2024.09.026 · PMID 39406578

     Seven studies, 409 patients; head-to-head area under the curve 0.97 against 0.80, specificity 94% against 66%. PubMed dates the record 2024; its print issue, 32(5), belongs to 2025.

113. 113
     Guo W, Xu W, Meng T, et al. FAP-targeted PET/CT imaging in patients with breast cancer from a prospective bi-center study: insights into diagnosis and clinic management.Eur J Nucl Med Mol Imaging · 2025 · 52(7):2317-2334doi:10.1007/s00259-025-07108-2 · PMID 39883140

     Prospective, two centers, 61 patients; sensitivity for the primary tumor 100% against 79% for FDG; management changed in 9 of 59.

114. 114
     Gupta N, Purohit P, Sood S, Rana A. Fibroblast activation protein inhibitor PET/computed tomography versus 18F-fluorodeoxyglucose PET/computed tomography in inflammatory bowel disease: a systematic review and exploratory meta-analysis with focus on ulcerative colitis.Nucl Med Commun · 2026 · published online 17 Julydoi:10.1097/MNM.0000000000002209 · PMID 42461088

     Eleven studies; an exploratory segment-level synthesis only, with no patient-level pooled estimate.

115. 115
     Rowe SP, Buck A, Bundschuh RA, et al. [18F]DCFPyL PET/CT for Imaging of Prostate Cancer.Nuklearmedizin · 2022 · 61(3):240-246doi:10.1055/a-1659-0010 · PMID 35030637

     Review noting the United States approval of piflufolastat F 18 after the OSPREY and CONDOR trials; a narrative review.

116. 116
     Yan Y, Zhuo H, Li T, et al. Advancements in PSMA ligand radiolabeling for diagnosis and treatment of prostate cancer: a systematic review.Front Oncol · 2024 · 14:1373606doi:10.3389/fonc.2024.1373606 · PMID 38577331

     Systematic review recording United States Food and Drug Administration approval of gallium-68 PSMA-11 for imaging and lutetium-177 PSMA-617 for therapy.

117. 117
     Fendler WP, Eiber M, Beheshti M, et al. PSMA PET/CT: joint EANM procedure guideline/SNMMI procedure standard for prostate cancer imaging 2.0.Eur J Nucl Med Mol Imaging · 2023 · 50(5):1466-1486doi:10.1007/s00259-022-06089-w · PMID 36604326

     Joint European and American procedure guideline; a consensus document, not outcome evidence.

118. 118
     Malan N, Vangu MD. Normal Variants, Pitfalls, and Artifacts in Ga-68 Prostate Specific Membrane Antigen (PSMA) PET/CT Imaging.Front Nucl Med · 2022 · 2:825512doi:10.3389/fnume.2022.825512 · PMID 39354969

     Review calling 'prostate specific' a misnomer because the protein, a folate hydrolase, appears in other benign and malignant conditions; a narrative review.

119. 119
     Meena A, Singh H, Mittal BR, Kumar R, Goyal S. 18F-PSMA Expression in Amoebic Liver Abscesses Mimics as Metastatic Prostate Cancer.Clin Nucl Med · 2025 · 51(5):e326-e327doi:10.1097/RLU.0000000000006138 · PMID 41021891

     One case; PSMA uptake in the periphery of early amebic liver lesions that ultrasound had read as necrotic hepatic metastases. PubMed dates the record 2025; its print issue, 51(5), belongs to 2026.

120. 120
     Schiller EL, Bueding E, Turner VM, Fisher J. Aerobic and anaerobic carbohydrate metabolism and egg production of Schistosoma mansoni in vitro.J Parasitol · 1975 · 61(3):385-89PMID 1169294

     Adult schistosomes used glucose and made lactate at the same rate with or without oxygen, showing no Pasteur effect; in vitro, says nothing about PET signal.