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Purpose: Dialysis patients are at an increased risk of developing renal cell carcinoma (RCC); however, differentiating between RCC and benign cysts can sometimes be difficult using modalities, such as computed tomography (CT) and ultrasonography. 18 F-Fluorodeoxyglucose positron emission tomography (FDG-PET)/CT efficiently detects malignant tumors; however, physiological accumulation of FDG in the kidney limits its efficacy in detecting renal tumors. However, in patients with severely impaired renal function, the renal accumulation of FDG is decreased, possibly improving the detection of renal malignancies in this patient population. This study evaluated the usefulness of FDG-PET/CT as a screening tool for detecting RCC in patients with end-stage renal disease., Materials and Methods: This prospective study recruited 150 participants from 2012 to 2016 who were on dialysis or underwent renal transplantation and were on dialysis until transplantation. FDG-PET/CT was performed to screen for RCC. Three radiologists independently evaluated the images. No protocol was defined for the additional management of positive examinations, leaving decisions to the discretion of each participant. Negative examinations were observed until the end of 2019., Results: In total, 150 participants (mean age, 58 ± 13 years; 105 men) underwent FDG-PET/CT. Twenty patients (13.4%) were diagnosed as positive. Fifteen patients underwent additional examinations and/or procedures, and RCC was found in seven patients. Of the four patients who underwent surgical resection, the pathological results were clear cell RCC in one, papillary RCC in one, and acquired cystic disease-associated RCC in two. Two participants were diagnosed with RCC on bone biopsy, and one was diagnosed on dynamic CT but opted for observation. The sensitivity, specificity, and negative predictive value were 100%, 93.9%, and 100%, respectively., Conclusion: FDG-PET/CT was useful for detecting RCC in patients with end-stage renal disease. Our findings show the potential use of FDG-PET/CT as a screening tool for RCC in this patient population., (© 2024. The Author(s).)

Metformin is widely used to treat diabetes, but induces changes in glucose uptake in both normal organs and tumors. Here, we review the effects of metformin on the uptake of 1 8 F-fludeoxyglucose ( 18 F-FDG) in tissues and tumors, and its influence on 18 F-FDG positron emission tomographic imaging ( 18 F-FDG PET), as well as the mechanisms involved. This is an important issue, because metformin has diverse effects on tissue uptake of 18 F-FDG, and this can affect the quality and interpretation of PET images. Metformin increases glucose uptake in the gastrointestinal tract, cerebral white matter, and the kidney, while regions of the cerebrum associated with memory show decreased glucose uptake, and the myocardium shows no change. Hepatocellular carcinoma and breast cancer show increased glucose uptake after metformin administration, while thyroid cancer shows decreased uptake, and colon and pancreatic cancers show no change. A high-energy diet increases 18 F-FDG uptake, but this effect is blocked by metformin. Withdrawal of metformin 48 h before PET image acquisition is widely recommended. However, based on our review of the literature, we propose that the differentiation of metformin discontinuation could be reasonable. But future clinical trials are still needed to support our viewpoint.

Objectives: Molecular imaging constitutes a promising technique for the early detection of rheumatoid arthritis (RA). Macrophages and hypoxia play significant roles in inflamed synovium. In the present study, we evaluated the efficacy of radiopharmaceuticals that target macrophage mannose receptors ( 99m Tc-labeled mannosylated dextran or 99m Tc(CO) 3 -DCM20) and hypoxia (copper(II) diacetyl-di(N 4 -methylthiosemicarbazone) or Cu-ATSM) for the early detection of RA in collagen-induced arthritis (CIA) mice models., Methods: CIA model was developed in DBA/1 mice, and the clinical score for arthritis was visually assessed on a regular basis. Two biodistribution studies were performed in a paired-labeled format using 2-deoxy-2- 18 F-fluoro-D-glucose ( 18 F-FDG) as a reference: (1) 99m Tc(CO) 3 -DCM20 with 18 F-FDG and (2) 67 Cu-ATSM with 18 F-FDG., Results: The accumulation levels of 99m Tc(CO) 3 -DCM20 and 67 Cu-ATSM in forepaws, hindpaws, and knee joints of CIA mice were significantly higher than that of control mice. In contrast, 18 F-FDG uptake in hindpaws and knee joints showed no significant difference between CIA and control mice. The radioactivity levels of 99m Tc(CO) 3 -DCM20 and 67 Cu-ATSM were significantly correlated with the clinical scores for the paws., Conclusion: These results suggest the potential usefulness of 99m Tc(CO) 3 -DCM20 and radiolabeled Cu-ATSM for the imaging and early detection of RA.

Positron emission tomography (PET) imaging with 18 F-labeled α-methyl-substituted amino acids exerts significant influence on differential diagnosis of malignant tumors and tumor-like lesions. Exclusive uptake via L-type amino acid transporter 1 (LAT1), a tumor-specific transporter, accounts for their excellent tumor specificity and low background accumulation. However, further refinement and optimization in their tumor accumulation and pharmacokinetics are sorely needed. To address these issues, we newly designed 18 F-labeled α-methyl-phenylalanine ( 18 F-FAMP) regioisomers (2-, 3-, or 4- 18 F-FAMP) and stereoisomers (L- or D-form), and we comprehensively evaluated their potential as tumor-imaging agents. 18 F-FAMPs were prepared from α-methyl phenylalanine by electrophilic radiofluorination and purified by reversed-phase HPLC. In biodistribution studies on normal mice, L-2- 18 F-FAMP and the three D- 18 F-FAMPs showed faster blood clearance and lower renal accumulation than L-3- 18 F-FAMP or L-4- 18 F-FAMP. In LS180 human colorectal cancer cell line xenograft mice, L-2- 18 F-FAMP exhibited significantly higher tumor accumulation than the D- 18 F-FAMPs or a clinically relevant tracer, L-3- 18 F-α-methyl-tyrosine ( 18 F-FAMT) ( p < 0.05). The renal accumulation levels of L-2- 18 F-FAMP were significantly lower than that of 18 F-FAMT ( p < 0.01). LAT-1 specificity of L-2- 18 F-FAMP was validated in the cellular uptake studies. The PET imaging with L-2- 18 F-FAMP clearly visualized the tumor as early as 1 h after injection, and the high tumor accumulation level was retained for 3 h. These findings suggest that L-2- 18 F-FAMP constitutes a potential PET tracer for tumor-specific imaging.

18 F-Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is usually used to screen malignancy in patients with dermatomyositis (DM). Additionally, it is well known that FDG-PET/CT provides valuable information for evaluating the activity of several inflammatory diseases, such as sarcoidosis, atherosclerosis, inflammatory bowel disease and rheumatoid arthritis. Therefore, the objective of this study was to evaluate the clinical usefulness of FDG-PET/CT for the detection of inflammatory lesions and disease activity of both myopathy and interstitial lung disease (ILD) in DM patients. We measured the maximum standardized uptake value (SUVmax) in the muscles and lungs in 22 DM patients, and compared with magnetic resonance imaging (MRI) and high-resolution computed tomography (HRCT) findings in the same muscle and lung regions as well as with clinical findings. We found that the location of increased FDG uptake was nearly consistent with the region of ILD and myositis detected by HRCT or MRI, respectively. There was a significant positive correlation between lung HRCT score and SUVmax in each lung. Serum Krebs von den Lungen-6 levels also revealed significant positive correlation with total SUVmax of right and left lungs. Regarding FDG-PET/CT and myopathy, total SUVmax in the muscles was significantly correlated with serum cytokeratin levels. Our results suggest that FDG uptake (SUVmax) might be useful for not only the detection of malignant tumors, but also the evaluation of the location and activity of ILD and myositis in DM patients., (© 2019 Japanese Dermatological Association.)

18 F- or 131 I-labeled (4-fluoro-3-iodobenzyl)guanidine (FIBG) has been a promising yet unattainable derivative of radioiodine-labeled meta-iodobenzylguanidine (MIBG), because of the complex radiofluorination method. In this study, we proposed a 2-step radiosynthetic method to obtain 18 F-FIBG and evaluated the diagnostic and therapeutic potential of 18 F-FIBG and 131 I-FIBG in a pheochromocytoma model (PC-12). Methods: 18 F-FIBG was prepared from a (mesityl)(aryl)iodonium salt precursor in the presence of a copper catalyst. Biodistribution studies, PET imaging, and a therapeutic study were performed on the PC-12 xenograft mice with either 18 F- or 131 I-FIBG. The association between the therapeutic effect and the tumor uptake of pretherapy 18 F-FIBG PET was also evaluated. Results: The copper-mediated radiofluorination method readily yielded 18 F-FIBG, as well as its regioisomer, 18 F-IFBG. The isolated 18 F-FIBG showed a higher accumulation in the PC-12 xenograft tumor than in any other tissue. The high tumor uptake of 18 F-FIBG allowed clear tumor visualization in the PET images as early as 1 h after injection, with an excellent tumor-to-background ratio. A biodistribution study with 131 I-FIBG revealed its higher and prolonged retention in the tumor in comparison with 125 I-MIBG. As a result, a therapeutic dose of 131 I-FIBG delayed tumor growth significantly more than did 131 I-MIBG. The tumor uptake of 18 F-FIBG was proportional to the therapeutic effect of 131 I-FIBG. Conclusion: These results suggest the potential usefulness of FIBG as a diagnostic and therapeutic agent for the management of norepinephrine transporter (NET)-expressing tumors., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

Purpose: Dual-energy computed tomography (DECT) can be used for visual determination of iodine distribution in the myocardium (iodine image); however, the accuracy and reproducibility of the process remains debatable. Because of the low contrast-to-noise ratio of CT, we hypothesized that quantitative measurement may be more accurate for detecting myocardial ischemia. In this study, we evaluated our quantitative method by comparing it with visual analysis using Tc-tetrofosmin (TF) stress-rest single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) as the reference standard., Materials and Methods: Forty-three patients who had a significant stenosis on cardiac rest DECT and had received Tc-TF stress-rest SPECT MPI within 1 month were retrospectively analyzed. The regions of interest were set on iodine images in accordance with the American Heart Association (AHA) 17-segment model (a total of 731 segments). The regions of interest values were divided by the amount of iodine (mg) per unit weight (kg) and defined as perfusion value (perfusion value analysis). All segments were also visually analyzed and receiver operating characteristic curve analysis performed to identify the superior analysis., Results: The receiver operating characteristic curve analysis showed that perfusion value analysis is significantly superior to visual analysis [the area under the curve: 0.921 (95% confidence interval, 0.860-0.981) versus 0.685 (95% confidence interval, 0.580-0.791), respectively, P<0.05], with 93.8% sensitivity, 99.1% specificity, 98.9% accuracy, 83.3% positive predictive value, and 99.7% negative predictive value (P<0.01)., Conclusions: Quantitative analysis of the iodine image of rest DECT, called perfusion value analysis, is more accurate than visual analysis when compared with Tc-TF SPECT MPI as the reference standard.

Background: L-[3-18F]-α-methyltyrosine (18F-FAMT) solely accumulates in tumor cells via an amino acid transport system. This selective uptake pattern results in a very high tumor-to-background ratio, enabling clear delineation of the tumor. The purpose of the present study was to assess the significance of 18F-FAMT PET, which shows little nonspecific uptake compared to 18F-flourodeoxyglucose position emission tomography (FDG PET) in esophageal cancer patients., Methodology: PET-CT studies with 18F-FAMT and 18F-FDG were performed as part of pretreatment work-up in 82 patients with histologically confirmed esophageal cancer. We evaluated nonspecific uptakes of 18F-FDG and 18F-FAMT PET., Results: The nonspecific uptake of 18F-FAMT PET was lower than that of 18F-FDG PET (p = 0.282). In the operation group, 26.1% demonstrated nonspecific uptake in 18F-FDG PET, whereas only 2.38% (1 case) demonstrated nonspecific uptake in 18F-FAMT PET (p = 0.433). In the inoperable group, 47.5% showed nonspecific uptake in 18F-FDG PET, whereas 5.0% showed nonspecific uptake in 18F-FAMT PET (p = 0.079)., Conclusion: A crucial point for the diagnostic value of PET is distinguishing specific and nonspecific uptake. 18F-FAMT-PET is a very superior modality with regard to the lower rate of nonspecific uptake in esophageal cancer., (© 2017 S. Karger AG, Basel.)

We aimed evaluate F-fluorodeoxyglucose uptake at major joints for differentiating patients with rheumatoid arthritis (RA) from those with non-RA arthritis using F-fluorodeoxyglucose (FDG)-positron emission tomography (PET).Eighteen patients with RA (13 women; age, 66.8 ± 13.2 years) and 17 patients with non-RA (6 women; age, 50.8 ± 12.5 years) were included. Twelve joints of each patient were examined: shoulder, elbow, wrist, hip, knee, and ankle on both sides. A visual scoring (VS) system was used; quantitative parameters such as maximum standardized uptake value (SUVmax), metabolic active volume (MAV), and total lesion glycolysis (TLG) were evaluated. Total score and value of each parameter were compared between the RA and non-RA groups.Total VS score (mean, 37.7 ± 9.0 vs 21.9 ± 7.2; P < .0001) and SUVmax (mean, 28.1 ± 8.5 vs 17.9 ± 5.8; P < .001) were significantly higher in the RA group than in the non-RA group. A significant between-group difference was also observed with respect to total MAV (608.3 ± 370.7 vs 176.5 ± 217.8; P < .001) and total TLG (1139.3 ± 759.1 vs 289.5 ± 395.4; P < .001). Receiver operating characteristic curve analysis revealed that total VS had the highest area under curve (.92), with sensitivity and specificity of 88.9% and 76.4%, respectively.Quantitative PET parameters could differentiate RA from non-RA. Total VS score, however, appears to be the best convenient qualitative tool for diagnosing RA.

Purpose: The aim of the current study was to evaluate the utility of F-18-fluoro-2-deoxy-D-glucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) in assessing patients diagnosed with immunoglobulin G4 (IgG4)-related disease (IgG4-RD) with inflammation of the head and neck glands., Methods: We reviewed the records of 17 patients (16 men and 1 woman) with IgG4-RD exhibiting inflammation of the head and neck glands (lacrimal or salivary glands; LSG) who were diagnosed by excisional biopsy of the LSG. F-18 FDG PET/CT images were retrospectively evaluated for locations of high FDG accumulation, and the maximum standardized uptake value (SUVmax) of each lesion was calculated., Results: In 15 of 17 patients (88 %), FDG accumulation was observed in organs outside of the biopsied LSG. High FDG accumulation was most frequently seen in the lymph node (71 %), followed by the non-biopsied LSG (41 %). FDG accumulation was also found in other typically affected organs including the prostate and retroperitoneum (18 %), kidney and lung (12 %), and pancreas (1 %). FDG accumulation was most commonly observed in two lesions outside of the biopsied site (41 %)., Conclusions: Detection of the multi-organ involvement before treatment is important for patients with IgG4-RD. F-18 FDG PET/CT is an effective tool for assessing the location of extra-LSG lesions in patients with IgG4-RD with LSG inflammation.

Background/aim: The amino acid positron emission tomography (PET) tracer [(18)F]-3-fluoro-alpha-methyltyrosine ((18)F-FAMT) is known to be highly specific for malignancies. We evaluated the accumulation of (18)F-FDG or (18)F-FAMT in lymph nodes (LN) prior to definitive chemoradiotherapy (CRT) for esophageal cancer., Patients and Methods: We retrospectively reviewed 30 patients with esophageal squamous cell carcinoma. All patients received definitive CRT. The relationship between the accumulation of (18)F-FDG PET or (18)F-FAMT PET in LNs prior to CRT and clinical outcomes was assessed., Results: A correlation was observed between LNs in which most of (18)F-FAMT was accumulated and complete response (CR) rate, but was not for (18)F-FDG. Additionally, for (18)F-FAMT, the CR rate was significantly higher in the LN accumulated lesion ≤ 1 group than in the LN accumulated lesion >2 group., Discussion: To predict the outcome of definitive CRT in patients with esophageal cancer, it is important to evaluate the LN status., (Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Background: [18F]-3-fluoro-alpha-methyl tyrosine (18F-FAMT) as an amino acid tracer in positron emission tomography (PET) has been widely investigated in several tumor types. Herein we investigated the clinical significance of 18F-FAMT PET uptake as a prognostic marker together in our updated data of patients with esophageal cancer., Patients and Methods: We retrospectively assessed the treatment outcomes of 42 patients with histologically-confirmed esophageal cancer. The survival rate was analyzed using the median peak standardized uptake value (SUV) with 2.2 as the cut-off value., Results: FAMT uptakes were significantly correlated with factors reflecting tumor progression. Moreover, a significant correlation was observed between FAMT uptake and disease-free survival (p=0.023). Moreover, on evaluation of individual lymph node groups, the specificity and positive predictive value were significantly higher for 18F-FAMT-PET than for 18F-FDG-PET and computed tomography (CT)., Conclusion: 18F-FAMT is an important pre-treatment diagnostic modality and its accumulation is a good predictor of disease-free survival (DFS) in patients with operable esophageal cancer., (Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Background: Hepatic angiomyolipoma is a rare benign mesenchymal tumor. We report an unusual case of a patient with multiple hepatic angiomyolipomas exhibiting high (18) F-fluorodeoxyglucose (FDG) uptake., Case Presentation: A 29-year-old man with a medical history of tuberous sclerosis was admitted to our hospital for fever, vomiting, and weight loss. Abdominal dynamic computed tomography revealed faint hypervascular hepatic tumors in segments 5 (67 mm) and 6 (10 mm), with rapid washout and clear borders; however, the tumors exhibited no definite fatty density. Abdominal magnetic resonance imaging revealed that the hepatic lesions were slightly hypointense on T1-weighted imaging, slightly hyperintense on T2-weighted imaging, and hyperintense with no apparent fat component on diffusion-weighted imaging. FDG-positron emission tomography (PET) imaging revealed high maximum standardized uptake values (SUVmax) of 6.27 (Segment 5) and 3.22 (Segment 6) in the hepatic tumors. A right hepatic lobectomy was performed, and part of the middle hepatic vein was also excised. Histological examination revealed that these tumors were characterized by the background infiltration of numerous inflammatory cells, including spindle-shaped cells, and a resemblance to an inflammatory pseudotumor. Immunohistochemical evaluation revealed that the tumor stained positively for human melanoma black-45. The tumor was therefore considered an inflammatory pseudotumor-like angiomyolipoma. Although several case reports of hepatic angiomyolipoma have been described or reviewed in the literature, only 3 have exhibited high (18) F-FDG uptake on PET imaging with SUVmax ranging from 3.3-4.0. In this case, increased (18) F-FDG uptake is more likely to appear, particularly if the inflammation is predominant., Conclusion: Although literature regarding the role of (18) F-FDG-PET in hepatic angiomyolipoma diagnosis is limited and the diagnostic value of (18) F-FDG-PET has not yet been clearly defined, the possibility that hepatic angiomyolipoma might exhibit high (18) F-FDG uptake should be considered.

Objectives: Adenocarcinoma in situ (AIS), which is considered to be pathologically non-invasive in the new International Association for the Study of Lung Cancer/the American Thoracic Society/the European Respiratory Society classification, might be present in patients who show a part-solid nodule on thin-section computed tomography (CT) scan., Methods: Between 2008 and 2011, 556 clinical Stage IA (c-Stage IA) lung cancer patients underwent pulmonary resection. For all the patients, the findings obtained by preoperative thin-section CT were reviewed and categorized as pure ground-glass nodule (GGN), part-solid nodule or pure-solid nodule based on the findings on thin-section CT, i.e. based on the consolidation/tumour ratio (CTR). A part-solid nodule was defined as a tumour with 0 < CTR < 1.0, which indicated focal nodular opacity that contained both solid and GGN components. All the patients were evaluated by positron emission tomography (PET), and the maximum standardized uptake value (SUVmax) was recorded. Several clinicopathological features were investigated to identify predictors of AIS in clinical Stage IA lung cancer patients with a part-solid nodule radiologically, using multivariate analyses., Results: One-hundred and twelve c-Stage IA lung cancer patients showed a part-solid appearance on thin-section CT. Among them, AIS was found in 10 (32%) of the tumours with 0 < CTR ≤ 0.5, in contrast to 3 (5%) with 0.5 < CTR < 1.0. According to multivariate analyses, SUVmax and CTR significantly predicted AIS in patients with a part-solid nodule (P = 0.04, 0.02). The mean SUVmax of the patients with AIS was 0.57 (0-1.6). Moreover, in the subgroup of part-solid nodule with a SUVmax of ≤1.0 and a CTR of ≤0.40, which were calculated as cut-off values for AIS based on the results for a receiver operating characteristic curve, 6 (40%) patients with these criteria showed a pathological non-invasive nature, even patients with a part-solid nodule., Conclusions: Among c-Stage IA adenocarcinoma with a part-solid nodule on thin-section CT scan, an extremely low level of SUVmax could reflect a pure GGN equivalent radiologically and AIS pathologically. The preoperative tumour SUVmax on PET could yield important information for predicting non-invasiveness in patients with a part-solid nodule.

Carcinoembryonic antigen (CEA) is an attractive target molecule of radioimmunotherapy (RIT). To enhance RIT's therapeutic efficacy, the fractionation of radiolabeled antibody doses is an attractive strategy. In this study, a fully human anti-CEA monoclonal antibody (mAb) C2-45 was selected by virtue of its lack of immunogenicity, and the effectiveness of fractionated RIT with yttrium-90 (⁹⁰Y)-labeled mAb C2-45 was evaluated. In LS180 tumor-bearing mice, indium-111 (¹¹¹In)-labeled mAb C2-45 showed high and persistent tumor accumulation. Therapeutic studies were performed with single doses of ⁹⁰Y-mAb C2-45 (100 or 200 μCi) or double doses of 100 μCi ⁹⁰Y-mAb C2-45 at different intervals (5, 10, and 15 days). All ⁹⁰Y-mAb C2-45-treated mice showed inhibition of tumor progression, while the time to tumor progression was much longer in both the 200-μCi-treated group and the double 100-μCi-treated group than in the single 100-μCi-treated group. The therapeutic effect of the double 100 μCi administration at days 0 and 15 lasted significantly longer than that in the other treatment groups. These findings indicate that ⁹⁰Y-mAb C2-45 may be a promising agent for the treatment of CEA-positive cancer and that the fractionation of ⁹⁰Y-labeled antibody doses could enhance the therapeutic effect if performed according to an appropriate protocol.

Aims: L-[3-(18)F]-α-Methyltyrosine ((18)F-FAMT) has high specificity for malignant tumors on positron emission tomography (PET), and its role and potential usefulness has been previously investigated in operable esophageal carcinoma. We aimed to assess the ability of (18)F-FAMT PET to predict the response of esophageal cancer to definitive chemoradiotherapy., Patients and Methods: We retrospectively reviewed 40 patients with esophageal cancer imaged with (18)F-FAMT PET. The relationship between (18)F-FAMT PET uptake before chemoradiotherapy and clinical outcomes was assessed., Results: The primary tumor was visualized in 95% patients. (18)F-FAMT uptake was significantly positively correlated with lymph node metastasis. The low-(18)F-FAMT accumulation group had significantly higher complete response (CR) rates than did the high-accumulation group. The addition of a lymph node metastasis category with low (18)F-FAMT uptake provides a more precise predictor of CR., Conclusion: (18)F-FAMT uptake prior to treatment is a good predictor of CR rate after CRT for esophageal cancer.

A 62-year-old male presented with sudden onset of low back and right leg pain. Contrast-enhanced computed tomography demonstrated an abdominal aortic aneurysm (AAA), along with a large mass lesion causing vertebral body erosion. Magnetic resonance imaging (MRI) suggested that the mass lesion consisted of a chronic hematoma. Fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) demonstrated increased uptake around the mass lesion, but not around the AAA. Surgical intervention was performed, and the subsequent histological diagnosis was chronic contained rupture of AAA. The mass lesion consisted of chronic hematoma and necrosis with inflammatory cell infiltration and hemosiderin deposition. This condition mimics some neoplastic diseases, but MRI and FDG-PET findings may help establish the correct diagnosis.

Aim: We investigated the significance of pre-treatment screening by (18)F-fluorodeoxyglucose positron-emission tomography (FDG-PET) in patients with esophageal cancer., Patients and Methods: We retrospectively evaluated the clinical significance of screening in 200 patients with primary esophageal cancer using FDG-PET., Results: Out of 200 patients, 34 (17%) had synchronous multiple primary tumors; 31 patients had two types of cancers (15.5%) and three patients had three types (1.5%). The 37 second and third primary tumors were 13 stomach cancers (35.1%), 13 head and neck cancers (35.1%), seven colon (18.9%) and two lung (5.4%) cancers. When PET was performed at initial treatment for esophageal cancer, the diagnostic sensitivity of FDG-PET/Computed tomography (CT) for the second and third synchronous primary cancer were 53.8% (7/13) for the stomach; head and neck, 61.5% (8/13); colon, 42.9% (3/7); and lung, 50% (1/2), for an overall sensitivity of 54.1% (20/37 sites)., Conclusion: FDG-PET/CT for patients with esophageal cancer may find both metastases from the primary esophageal cancer and other types of synchronous primary cancers.

Purpose: L-[3-(18)F]-α-Methyltyrosine ((18)F-FAMT) was developed as an amino acid tracer for PET imaging to provide better specificity than 2-[(18)F]fluoro-2-deoxy-D-glucose ((18)F-FDG) PET for cancer diagnosis. We investigated the diagnostic usefulness of (18)F-FAMT in oral squamous cell carcinoma (OSCC). The correlation between tumour uptake of (18)F-FAMT and L-type amino acid transporter 1 (LAT1) expression was determined., Methods: The study group comprised 68 OSCC patients who underwent both (18)F-FAMT and (18)F-FDG PET. Resected tumour sections were stained by immunohistochemistry for LAT1, CD98 and Ki-67, and microvessel density was determined in terms of CD34 and p53 expression., Results: The sensitivity of primary tumour detection by (18)F-FAMT and (18)F-FDG PET was 98 % and 100 %, respectively. The sensitivity, specificity and accuracy of (18)F-FAMT PET for detecting malignant lymph nodes were 68 %, 99 % and 97 %, respectively, and equivalent values for (18)F-FDG PET were 84 %, 94 % and 94 %, respectively. The specificity and accuracy of (18)F-FAMT were significantly higher than those of (18)F-FDG. The uptake of (18)F-FAMT was significantly correlated with LAT1 expression, cell proliferation and advanced stage. The expression of LAT1 in OSCC cells was closely correlated with CD98 levels, cell proliferation and angiogenesis., Conclusion: (18)F-FAMT PET showed higher specificity for detecting malignant lesions than (18)F-FDG PET. The uptake of (18)F-FAMT by OSCC cells can be determined by the presence of LAT1 expression and tumour cell proliferation.

Purpose: The usefulness of (18)F-FDG PET/CT for bone metastasis evaluation has already been established. The amino acid PET tracer [(18)F]-3-fluoro-alpha-methyl tyrosine ((18)F-FAMT) has been reported to be highly specific for malignancy. We evaluated the additional value of (18)F-FAMT PET/CT to complement (18)F-FDG PET/CT in the evaluation of bone metastasis., Methods: This retrospective study included 21 patients with bone metastases of various cancers who had undergone both (18)F-FDG and (18)F-FAMT PET/CT within 1 month of each other. (18)F-FDG-avid bone lesions suspicious for malignancy were carefully selected based on the cut-off value for malignancy, and the SUVmax of the (18)F-FAMT in the corresponding lesions were evaluated., Results: A total of 72 (18)F-FDG-positive bone lesions suspected to be metastases in the 21 patients were used as the reference standard. (18)F-FAMT uptake was found in 87.5 % of the lesions. In the lesions of lung cancer origin, the uptake of the two tracers showed a good correlation (40 lesions, r = 0.68, P < 0.01). Bone metastatic lesions of oesophageal cancer showed the highest average of (18)F-FAMT uptake. Bone metastatic lesions of squamous cell carcinoma showed higher (18)F-FAMT uptake than those of adenocarcinoma. No significant difference in (18)F-FAMT uptake was seen between osteoblastic and osteolytic bone metastatic lesions., Conclusion: The usefulness of (18)F-FAMT PET/CT for bone metastasis detection regardless of the lesion phenotype was demonstrated. The fact that (18)F-FAMT uptake was confirmed by (18)F-FDG uptake suggests that (18)F-FAMT PET/CT has the potential to complement (18)F-FDG PET/CT for the detection of bone metastases.

A 77-year-old man who had undergone mitral valve replacement 5 years previously presented with an intrapericardial mass. Computed tomography and magnetic resonance imaging showed that the mass lesion contained hematoma components. Positron-emission tomography (PET) with 2-[¹⁸F]fluoro-2-deoxy-D-glucose (FDG) revealed uptake in the peripheral rim of the mass. These findings suggested the presence of hematoma associated with a malignant lesion. Surgical resection was performed, and the histological diagnosis was chronic expanding intrapericardial hematoma without neoplastic changes. Chronic expanding intrapericardial hematoma is a rare disease but should be considered when an expanding mass is found in a patient after cardiac surgery. The FDG-PET findings of chronic expanding hematomas, including FDG uptake in the peripheral rim of the mass as a result of inflammation, should be recognized as a potential interpretive pitfall that mimics a malignant tumor.

Objectives: To evaluate whether there is a correlation between the differences in joint uptake of 2-[18F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) and the improvement of clinical findings in RA patients undergoing anti-TNF therapies., Methods: Twenty-two patients who received anti-TNF therapies, including infliximab for 16 patients and etanercept for 6 patients, were assessed. PET with (18)F-FDG studies and clinical assessments were performed at baseline and 6 months after the initiation of therapy. The maximal standardized uptake value (SUV(max)) was used as a representative value for the assessment of the FDG uptake in the bilateral shoulder, elbow, wrist, hip, knee and ankle joints. Spearman's rank correlation test was applied to assess the correlation between the SUV and the clinical parameters., Results: The ΔSUV (12 joints), the difference in the SUV(max) of the affected 12 joints before and after treatment, was positively correlated with the ΔDAS28 (r = 0.609, P = 0.003), ΔDAS28-CRP (r = 0.656, P = 0.001) and Δtender joint count (TJC) (r = 0.609, P = 0.003). There were also significantly positive correlations between ΔSUV (8 joints); the difference in the SUV(max) of the bilateral shoulder, elbow, wrist and knee joints before and after treatment and the ΔDAS28 (r = 0.642, P = 0.001), ΔDAS28-CRP (r = 0.712, P < 0.001) and ΔTJC (r = 0.608, P = 0.003), respectively., Conclusion: The FDG uptake observed in the inflamed RA joints may reflect disease activity. The FDG-PET response was correlated with the clinical response to the biologic treatment of RA.

A 63-year-old man underwent computed tomography (CT) using intravenous low-osmolar iodine contrast medium (LOCM) 6 days after undergoing high-dose (131)I-MIBG therapy for metastatic pheochromocytoma. Immediately after the CT examination, his blood pressure increased to 260/160 mmHg (from 179/101 mmHg before the examination). Phentolamine mesilate was administered, and the blood pressure rapidly went back to normal. Although hypertensive crisis after administration of LOCM is rare, this case suggests that high-dose (131)IMIBG therapy may be a risk factor for hypertensive crisis after administration of intravenous LOCM.

Hepatocellular carcinoma (HCC) has variable 18F-fluoro-2-deoxy-D-glucose (18F-FDG) uptake and the relationship between 18F-FDG uptake with the expression of glucose transporters (Gluts) and hexokinase II (HK-II) has not been extensively examined. Present study explored the role of 18F-FDG positron emission tomography (PET) as a clinical significance and the association with Gluts and HK-II in patients with HCC. Whole body 18F-FDG PET, immunohistochemistry and western blot analysis of Glut-1 to Glut-5 and HK-II were performed in 31 patients (24 male and 7 female, range 48-75 years) with HCC. Significant correlation was found between 18F-FDG uptake and overall expression of Glut-2 (rho=0.55, p=0.002) and HK-II (rho=0.37, p=0.04). Expression of HK-II was correlated with Glut-2 (rho=0.57, p=0.0009) but not with other Gluts, which indicated that Glut-2 is a major glucose transporter. The prognosis of patients with SUV >/=2 and positive Glut-2 were significantly worse than that with SUV <2 and negative Glut-2 (p=0.005 and p=0.03), respectively. Multivariate analysis showed that SUV and lymph node metastasis were independent prognostic factors. The present study indicated that combined evaluation of 18F-FDG uptake and expression of Glut-2 might have an important role for management of patients with HCC.

Objective: Recent studies have provided new insights into the role of lymph nodes (LNs) in rheumatoid arthritis (RA). The aim of this study was to evaluate the metabolic activity of the axillary LNs in relation to that of the upper limb joints and the clinical assessment of disease activity in RA patients treated with biologic therapies.Method: 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) scans were acquired for 64 patients with RA at baseline and after 6 months of biologic therapy, and the patients' clinical status was evaluated. The maximum standardized uptake value (SUVmax), metabolic active volume, and total lesion glycolysis (TLG) were used to assess glucose metabolism in the LNs and 12 joints. Clinical evaluations included serum markers and the Disease Activity Score based on 28-joint count-erythrocyte sedimentation rate (DAS28-ESR).Results: Changes in the SUVmax and TLG for the axillary LNs correlated significantly with those of the ipsilateral wrist joints. There was a positive correlation between the changes in the three metabolic parameters of the axillary LNs and the changes in disease activity after treatment. After 6 months of biologic therapy, all metabolic parameters for the axillary LNs in patients with a DAS28-ESR < 3.2 were significantly lower than those of patients with a DAS28-ESR ≥ 3.2.Conclusion: A relationship between the glucose metabolism of the axillary LNs and the ipsilateral wrist joints was demonstrated by the 18F-FDG-PET/CT parameters. The metabolic activity and active volume of axillary LNs may reflect the therapeutic response to the biologic treatment of RA. [ABSTRACT FROM AUTHOR]