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Byung-Tae Kim

Publications and source records attributed to Byung-Tae Kim.

At least 19 recordsLinked to original sources
PubMed2007

Use of integrated 18F-FDG PET/CT to improve the accuracy of initial cervical nodal evaluation in patients with head and neck squamous cell carcinoma.

BACKGROUND: We investigated the accuracy of performing cervical nodal evaluation with using integrated (18)F-fluoro deoxyglucose positron emission tomography (PET)/CT for squamous cell carcinoma (SCC) of the head and neck as compared with using PET and contrast-enhanced CT (CECT) alone. METHODS: The presence of metastatic lymphadenopathy in each cervical nodal group (level I-VI) and the nodal (N) classification of 47 patients with SCC of the head and neck were determined by using PET, CECT, and PET/CT, respectively, and the results were verified according to the histopathologic findings. RESULTS: Among the 91 foci that had abnormal uptake on PET, the combined PET/CT images provided additional information over PET for the anatomical localization and lesion characterization of 18 sites (19.8%) in 17 patients (36.2%). PET/CT also showed the best results among the three imaging modalities for the sensitivity, specificity, and accuracy (91.8, 98.9, and 97.1%, respectively) for predicting metastatic nodes on a level-by-level analysis, and PET/CT had a higher accuracy (85.1%) for the pathologic nodal classification over the clinical examinations (68.1%) or PET (70.2%). CONCLUSIONS: Combined PET/CT images are more accurate than the PET or CECT images alone for conducting cervical node evaluation in the patients suffering with head and neck SCC.

Aged↗
PubMed2006

Curcumin and dehydrozingerone derivatives: synthesis, radiolabeling, and evaluation for beta-amyloid plaque imaging.

Alzheimer's disease (AD) is pathologically characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain, and thus, the in vivo imaging of plaques and tangles would be beneficial for the early diagnosis of AD. It has been suggested that 5-hydroxy-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,4,6-heptatrien-3-one (curcumin) may be responsible for low age-adjusted prevalence of AD in India. In the present study, eight novel derivatives of curcumin and 4-(4-hydroxy-3-methoxyphenyl)-3-buten-2-one (dehydrozingerone) were synthesized and their binding affinities for beta-amyloid (Abeta) aggregates were measured. Of these ligands, fluoropropyl-substituted curcumin (8) showed the highest binding affinity (Ki=0.07 nM), and therefore, 8 was radiolabeled and evaluated as a potential probe for Abeta plaque imaging. Partition coefficient measurement and biodistribution in normal mice demonstrated that [18F]8 has a suitable lipophilicity and reasonable initial brain uptake. Metabolism studies also indicated that [18F]8 is metabolically stable in the brain. These results suggest that [18F]8 is a suitable radioligand for Abeta plaque imaging.

Amyloid↗
PubMed2006

Stage T1 non-small cell lung cancer: preoperative mediastinal nodal staging with integrated FDG PET/CT--a prospective study.

PURPOSE: To prospectively evaluate the sensitivity and specificity of integrated fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) and computed tomography (CT) (PET/CT) for the preoperative diagnosis of mediastinal nodal metastasis in stage T1 non-small cell lung cancer (NSCLC), with surgical and histologic results as reference standards. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. From June 2003 to February 2005, 150 patients (89 men and 61 women; mean age, 59 years) with stage T1 NSCLC at stand-alone CT underwent integrated PET/CT and surgical staging. Two observers (one radiologist and one nuclear medicine physician) evaluated prospectively and in consensus the mediastinal nodes by analyzing both PET (functional) and CT (anatomic) images. Nodal stages were determined by using the American Joint Committee on Cancer staging system and surgical and histologic findings as the reference standard. Statistical evaluation of malignant lymph nodes was performed on per-nodal-station and per-person bases. RESULTS: A total of 568 mediastinal nodal stations were evaluated. Nodes were positive for malignancy in 34 (23%) of 150 patients and 55 (10%) of 568 nodal stations. For depiction of malignant nodes, the respective sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of integrated PET/CT were 42% (23 of 55), 100% (513 of 513), 100% (23 of 23), 94% (513 of 545), and 94% (536 of 568) on per-nodal-station basis and 47% (16 of 34), 100% (116 of 116), 100% (16 of 16), 87% (116 of 134), and 88% (132 of 150) on a per-patient basis. CONCLUSION: Integrated FDG PET/CT provides high specificity and positive predictive value of mediastinal nodal staging in stage T1 NSCLC, although the sensitivity is low.

Adult↗
PubMed2006

Prognostic significance of vascular endothelial growth factor expression and microvessel density in esophageal squamous cell carcinoma: comparison with positron emission tomography.

BACKGROUND: This study investigated whether the expression of vascular endothelial growth factor (VEGF) in a primary tumor and the intratumoral microvessel density (MVD) were independent prognostic factors in patients with an esophageal squamous cell carcinoma (SCC) in comparison with positron emission tomography (PET) by using (18)F-fluorodeoxyglucose (FDG) and stage. METHODS: Fifty-one patients with a newly diagnosed esophageal SCC who underwent preoperative FDG-PET and esophagectomy with intent to cure were enrolled in this study. The VEGF expression level, the intratumoral MVD, and the Ki-67 labeling index were evaluated by using immunohistochemical staining. Only significant variables in the univariate survival analysis were examined by multivariate survival analysis with the Cox proportional hazards model. RESULT: Cancer-related deaths occurred in 17 of 51 patients during the follow-up. Univariate survival analysis showed that the pathologic stage, pNM, maximum standardized uptake value of the primary tumor, tumor length on PET, number of PET-positive lymph nodes, PET stage, Ki-67 labeling index, intratumoral MVD, and the presence of VEGF expression were significant prognostic predictors for the overall survival. Multivariate analysis revealed that the pathologic stage, number of PET-positive nodes (0, 1, 2, or > or = 3), intratumoral MVD (cutoff, 60/mm(2)), and presence of VEGF expression were independent significant prognostic predictors for overall survival. CONCLUSION: In addition to the pathologic stage, the intratumoral MVD, the presence of VEGF expression, and the number of FDG-PET-positive nodes were independent prognostic predictors in patients with an esophageal SCC undergoing curative surgery.

Adult↗
PubMed2006

Depressed heart rate response to vasodilator stress for myocardial SPECT predicts mortality in patients after myocardial infarction.

BACKGROUND: As heart rate (HR) response during vasodilator stress myocardial perfusion studies can be a marker of HR variability, we investigated its prognostic value in patients after myocardial infarction (MI). METHODS: Subjects were 147 survivors of MI who underwent vasodilator stress thallium-201 scintigraphy. HR response was measured as peak to basal (P/B) ratios during vasodilator infusion. End points for survival analysis were all-cause deaths, non-fatal recurrent MI, and soft events. RESULTS: HR response was significantly depressed in the post-MI patients compared to controls (p<0.0005). HR response correlated to LVEF (r=0.37, p<0.0001) and summed stress scores (r=-0.18, p<0.05), but not with antianginal medication. During 58+/-30 mo of follow-up, there were 15 deaths, 7 recurrent MI, and 11 soft events. Low HR response, old age, low LVEF, and high difference score were significant univariate risk factors for death. Multivariate analysis identified low HR response (p=0.03), high stress score (p=0.02), and low LVEF (p=0.05) as independent predictors of mortality. The predictive value of HR response was incremental to that offered by other variables (p=0.02). CONCLUSIONS: HR response, readily attained during vasodilator stress myocardial perfusion studies, may provide useful additional prognostic information in post-MI patients.

Analysis of Variance↗
PubMed2006

Mycobacterium abscessus pulmonary infection presenting as a solitary pulmonary nodule.

Nontuberculous mycobacterial pulmonary infection is a rare cause of a solitary pulmonary nodule. All previously reported cases were caused by Mycobacterium avium complex, and a solitary pulmonary nodule caused by other NTM species has been very rarely reported. We describe the first case of Mycobacterium abscessus infection presenting as a solitary pulmonary nodule in a 51-year-old asymptomatic adult patient.

Female↗
PubMed2006

Pharmacokinetics and biodistribution of a small radioiodine labeled nerve growth factor fragment.

Nerve growth factor (NGF) exerts various actions on neuronal and non-neuronal tissues and has potential therapeutic utility, but difficulties in using the whole protein have stimulated interest in small NGF fragments. We radioiodinated a small cyclic peptide derived from NGF using the Bolton-Hunter method [125I-C(92-96)], and confirmed binding to high affinity NGF receptors by cross-linkage analysis. Pharmacokinetic characteristics in intravenously injected mice were T 1/2 alpha 5.2 min, T 1/2beta 121.3 min, clearance 11.8+/-0.5 ml/min, and volume of distribution 69.7+/-4.6 ml. Dose-proportionate increases in areas-under-curve and peak-concentrations indicated linear pharmacokinetics. Biodistribution data revealed that clinically relevant doses allowed C(92-96) accumulation sufficient to elicit biological responses in receptor expressing organs including the lungs, liver, spleen, and pancreas.

Animals↗
PubMed2006

Is subnanomolar binding affinity required for the in vivo imaging of acetylcholinesterase? Studies on 18F-labeled G379.

Acetylcholinesterase (AChE) is an important cholinergic marker of Alzheimer's disease (AD) and shows reduced activity in postmortem AD brain tissues. 1-(4-Fluorobenzyl)-4-[(5,6-dimethoxy-1-oxoindan-2-fluoro-2-yl)methyl]piperidine (G379, ), an AChE inhibitor with a subnanomolar IC(50) (0.56 nM), was prepared as a (18)F-labeled radioligand ([(18)F]) and evaluated in mice. Metabolism studies of [(18)F] showed no metabolites in the mouse brain. Tissue distribution studies demonstrated its uniform regional distribution in the mouse brain, suggesting that this radioligand is not suitable for the in vivo imaging of AChE. This result along with reports on radiolabeled N-benzylpiperidine lactam benzisoxazole (IC(50) < 1 nM) and other radiolabeled benzylpiperidine derivatives (IC(50) > 1 nM) suggested that a subnanomolar IC(50) may not be the only important factor in determining the suitability of a radioligand for in vivo studies of AChE.

Acetylcholinesterase↗
PubMed2006

In vitro metabolism studies of (18)F-labeled 1-phenylpiperazine using mouse liver S9 fraction.

The in vitro metabolism of 1-(4-[(18)F]fluoromethylbenzyl)-4-phenylpiperazine ([(18)F]1) and 1-(4-[(18)F]fluorobenzyl)-4-phenylpiperazine ([(18)F]2) was investigated using mouse liver S9 fraction. Results were compared to those of in vivo metabolism using mouse blood and bone and to in vitro metabolism using mouse liver microsomes. Defluorination was the main metabolic pathway for [(18)F]1 in vitro and in vivo. Based on TLC, HPLC and LC-MS data, [(18)F]fluoride ion and less polar radioactive metabolites derived from aromatic ring oxidation were detected in vitro, and the latter metabolites were rapidly converted into the former with time, whereas only the [(18)F]fluoride ion was detected in vivo. Similarly, the in vitro metabolism of [(18)F]2 using either S9 fraction or microsomes showed the same pattern as the in vivo method using blood; however, the radioactive metabolites derived from aromatic ring oxidation were not detected in vivo. These results demonstrate that liver S9 fraction can be widely used to investigate the intermediate radioactive metabolites and to predict the in vivo metabolism of radiotracers.

Animals↗
PubMed2006

Synthesis and evaluation of 4-[(18)F]fluorothalidomide for the in vivo studies of angiogenesis.

In this study, we prepared 2-(2,6-dioxopiperidin-3-yl)-4-[(18)F]fluoroisoindole-1,3-dione (4-[(18)F]fluorothalidomide; [(18)F]1) for the in vivo studies of angiogenesis. Radiochemical synthesis of [(18)F]1 was carried out by labeling 4-trimethylammoniumthalidomide trifluoromethanesulfonate with nBu(4)N[(18)F]F in dimethyl sulfoxide (DMSO), followed by reverse-phase HPLC purification. Decay-corrected radiochemical yield of [(18)F]1 was 50-60%, with an effective specific activity of 42-120 GBq/micromol (end of synthesis). Incubation of the radioligand with human umbilical vein endothelial cells (HUVEC-C; American Type Culture Collection) showed a time-dependent increase in the uptake of the radioligand, and the uptake was inhibited by 8-11% in the presence of 10 microM thalidomide, indicating nonspecific binding of the radioligand. Positron emission tomography (PET) images of mice implanted with tumors in their right flanks revealed a marked accumulation of radioactivity in the livers, kidneys and bladders of the mice, and brain uptake appeared at approximately 40 min after injection. However, no radioactivity uptake was detected in the implanted tumor. Thin-layer chromatography (TLC), HPLC and LC-MS analyses of mouse liver microsomal metabolites of [(18)F]1 and 1 with or without nicotinamide adenine dinucleotide phosphate (NADPH) clearly revealed that the radioligand did not go through metabolic activation but underwent nonenzymatic hydrolysis at physiological pH. Therefore, these results would appear to indicate that [(18)F]1 may not be suitable for the in vivo studies of angiogenesis at least in mice, although it was reported that thalidomide and/or its hydrolysis products may be responsible for its activity in humans.

Animals↗
PubMed2006

Incidence and radio-uptake patterns of femoral head avascular osteonecrosis at 1 year after renal transplantation: a prospective study with planar bone scintigraphy.

OBJECTIVES: We prospectively investigated the incidence of femoral head avascular osteonecrosis (AVN) and radio-uptake patterns of femoral heads on bone scintigraphy at 1 year after renal transplantation. METHODS: A total of 237 subjects (473 femoral heads) were included. A bone scintigraphy was performed at 12 +/- 1.1 months after renal transplantation, and 17 hips were painful at the time of bone scintigraphy. We graded the radioactivity in each femoral head as normal (grade 0), mildly increased (grade I), and definitely increased (grade II). Typical photon defects in the upper lateral femoral heads were evaluated separately. AVN was confirmed with clinical follow-up of more than 1 year and MRI and/or plain radiography findings. RESULTS: Femoral head AVN was detected in 15 of the 237 patients and 23 of the 473 femoral heads. When grade I and II activities were used as positive criteria, bone scintigraphy had a sensitivity of 91.3% (100% with pain) and specificity of 74.0% (100% with pain) for AVN diagnosis. When only grade II activity was considered positive, the rates were 56.5% (80.0% with pain) and 99.5% (100% with pain), respectively. The presence of a typical photon defect had a low sensitivity of 47.8%, although the specificity was high (99.1%). CONCLUSIONS: The incidence of femoral head AVN was low among a prospective cohort of renal transplantation recipients at the time of 1 year after engraftment. Planar bone scintigraphy is sufficient to diagnose AVN in symptomatic patients at risk for femoral head AVN using grade I and II activities as positive criteria.

Adult↗
PubMed2006

Focal parenchymal lung lesions showing a potential of false-positive and false-negative interpretations on integrated PET/CT.

OBJECTIVE: We describe a number of benign focal lung lesions with increased 18F-FDG uptake that simulate lung cancer and malignant lesions that lead to false-negatives due to little 18F-FDG uptake on integrated PET/CT images. CONCLUSION: The integration of clinical history, morphologic findings of lung parenchymal lesions on the CT component, and metabolic activities on the PET component of integrated PET/CT can help reduce false interpretation of the study. A lung biopsy may be needed for lesions showing increased 18F-FDG uptake on PET for tissue confirmation irrespective of their morphology on CT.

Adult↗
PubMed2006

Sentinel lymph node radiolocalization with 99mTc filtered tin colloid in clinically node-negative squamous cell carcinomas of the oral cavity.

The objective of this study was to evaluate the feasibility of sentinel lymph node biopsy by using a radiotracer lymphatic mapping technique in patients with squamous cell carcinoma of the oral cavity, and the diagnostic value of this technique. We studied twenty patients with previously untreated squamous cell carcinomas of the oral cavity and N0 necks. After the peritumoral injection of 99mTc filtered tin colloid preoperatively, lymphoscintigraphy and intraoperative mapping using a gamma detector were performed to localize sentinel nodes. An open biopsy of the sentinel node was followed by complete neck dissection. We identified the sentinel nodes in 19 of 20 patients (95.0%) by lymphoscintigraphy and in all (100%) by intraoperative gamma detector. In all cases, the status of the sentinel node accurately predicted the pathologic status of the neck with the false negative rate being 0%. The negative predictive value for the absence of cervical metastases was 100%. In conclusion, our radiolocalization technique of sentinel nodes using 99mTc filtered tin colloid in N0 squamous cell carcinomas of the oral cavity is technically feasible and appears to accurately predict the presence of the occult metastatic disease.

Adult↗
PubMed2006

Characteristics and regulation of 123I-MIBG transport in cultured pulmonary endothelial cells.

UNLABELLED: 123I-Metaiodobenzylguanidine (123I-MIBG) is used for lung scintigraphy to assess pulmonary endothelial cell integrity, but its processing at the cellular level has not been investigated to date. We thus characterized the mechanisms that mediate 123I-MIBG transport in pulmonary endothelial cells and investigated the effects of stimuli associated with pulmonary dysfunction. METHODS: Calf pulmonary artery endothelial (CPAE) cells were examined for 123I-MIBG uptake and efflux rates and evaluated for the presence of norepinephrine (NE) transporters by Western blotting. The specificity of 123I-MIBG uptake was investigated with inhibitors of the uptake 1 and uptake 2 transport systems. In addition, we tested the effects of hypoxia (1% O2), phorbol 12-myristate 13-acetate (PMA, a protein kinase C [PKC] activator), and NG-nitro-L-arginine methyl ester (L-NAME) (a nitric oxide synthase inhibitor) treatments on CPAE cell 123I-MIBG uptake. RESULTS: CPAE cells demonstrated a time-dependent increase in 123I-MIBG uptake that reached a relative plateau (mean +/- SD) at 4 h of 375.6% +/- 5.9% the 30-min level. When the culture medium was changed after 30 min of uptake, 123I-MIBG gradually was eluted from the cells at an efflux rate of 43.8% over 2 h. Western blotting confirmed the presence of NE transporters in CPAE cells. The uptake 1 inhibitors desipramine, imipramine, and phenoxybenzamine at 50 micromol/L reduced 123I-MIBG uptake to 55.3% +/- 2.7%, 62.4% +/- 3.5%, and 48.0% +/- 2.2% control levels, respectively, whereas none of the uptake 2 inhibitors had an effect. Exposure to hypoxia resulted in a reduction in 123I-MIBG uptake to 77.5% +/- 0.2% and 50.0% +/- 3.4% control levels at 0.5 and 4 h, respectively. PMA (10 ng/mL) and L-NAME (2 nmol/L) decreased 123I-MIBG uptake to 76.7% +/- 9.0% and 86.5% +/- 5.6% control levels, respectively. CONCLUSION: Pulmonary endothelial cells express NE transporters and actively take up 123I-MIBG through the specific uptake 1 system. Furthermore, 123I-MIBG transport can be reduced by hypoxia, PKC activation, and nitric oxide deficiency, which may contribute partly to the lower levels of lung uptake observed in diseases that compromise pulmonary endothelial cell integrity.

3-Iodobenzylguanidine↗
PubMed2006

Tissue characterization of solitary pulmonary nodule: comparative study between helical dynamic CT and integrated PET/CT.

UNLABELLED: Recent advances in the technology of helical multidetector CT allow precise evaluations of nodule hemodynamics. In addition, the efficacy of tissue characterization has improved, and now sensitivity and specificity of >90% are achieved. Moreover, the efficacy of PET for the tissue characterization of solitary pulmonary nodules (SPNs) has also become of importance. The purpose of this study was to compare the diagnostic accuracy of helical dynamic (HD) CT (HDCT) and integrated PET/CT for pulmonary nodule characterization. METHODS: One hundred nineteen patients with an SPN underwent both HDCT (unenhanced scans, followed by series of images at 30, 60, 90, 120 s and at 5 and 15 min after intravenous injection of contrast medium) and integrated PET/CT. On HDCT, a nodule was regarded as malignant with a net enhancement of > or =25 Hounsfield units (HU) and a washout of 5-31 HU. On integrated PET/CT, nodules were considered malignant with a > or =3.5 maximum standardized uptake value and an 18F-FDG uptake greater than that of mediastinal structures. The sensitivity, specificity, and accuracy of the 2 modalities for malignancy were compared using the McNemar test. RESULTS: There were 79 malignant and 40 benign nodules. The sensitivity, specificity, and accuracy for malignancy on HDCT were 81% (64/79 nodules), 93% (37/40), and 85% (101/119), respectively, whereas those on integrated PET/CT were 96% (76/79), 88% (35/40), and 93% (111/119), respectively (P = 0.008, 0.727, and 0.011, respectively). All malignant nodules were interpreted correctly on either HDCT or PET/CT. CONCLUSION: Integrated PET/CT is more sensitive and accurate than HDCT for the malignant nodule characterization; therefore, PET/CT may be performed as the first-line evaluation tool for SPN characterization. Because HDCT has high specificity and acceptable sensitivity and accuracy, it may be a reasonable alternative for nodule characterization when PET/CT is unavailable.

Adult↗
PubMed2006

Focal thyroid lesions incidentally identified by integrated 18F-FDG PET/CT: clinical significance and improved characterization.

UNLABELLED: In this retrospective study, we investigated whether the (18)F-FDG uptake pattern and CT findings improved the accuracy over the standardized uptake value (SUV) for differentiating benign from malignant focal thyroid lesions incidentally found on (18)F-FDG PET/CT. We also defined the prevalence of these lesions and their risk for cancer. METHODS: (18)F-FDG PET/CT was performed on 1,763 subjects without a previous history of thyroid cancer from May 2003 to June 2004. Two nuclear medicine physicians and 1 radiologist interpreted PET/CT images, concentrating on the presence of focal thyroid lesions, the maximum SUV of the thyroid lesion, the pattern of background thyroid (18)F-FDG uptake, and the CT attenuation pattern of the thyroid lesion. RESULTS: The prevalence of focal thyroid lesions on PET/CT was 4.0% (70/1,763). Diagnostic confirmation was done on 44 subjects by ultrasonography (US)-guided fine-needle aspiration (n = 29) or US with clinical follow-up (n = 15). Among 49 focal thyroid lesions in these 44 subjects, 18 focal thyroid lesions of 17 subjects were histologically proven to be malignant (papillary cancer in 16, metastasis from esophageal cancer in 1, non-Hodgkin's lymphoma in 1). Therefore, the cancer risk of focal thyroid lesions was 36.7% on a lesion-by-lesion basis or 38.6% on a subject-by-subject basis. The maximum SUV of malignant thyroid lesions was significantly higher than that of benign lesions (6.7 +/- 5.5 vs. 10.7 +/- 7.8; P < 0.05). When only the maximum SUV was applied to differentiate benign from malignant focal thyroid lesions for the receiver-operating-characteristic curve analysis, the area under the curve (AUC) of PET was 0.701. All 16 focal thyroid lesions with very low attenuation or nonlocalization on CT images, or with accompanying diffusely increased thyroid (18)F-FDG uptake, were benign. When those lesions were regarded as benign lesions, irrespective of the maximum SUV, the AUC of PET/CT was significantly improved to 0.878 (P < 0.01). CONCLUSION: Focal thyroid lesions incidentally found on (18)F-FDG PET/CT have a high risk of thyroid malignancy. Image interpretation that includes (18)F-FDG uptake and the CT attenuation pattern, along with the SUV, significantly improves the accuracy of PET/CT for differentiating benign from malignant focal thyroid lesions.

Adult↗
PubMed2006

18F-FDG PET/CT of thymic epithelial tumors: usefulness for distinguishing and staging tumor subgroups.

UNLABELLED: The purpose of our study was to assess the usefulness of integrated PET/CT using 18F-FDG for distinguishing thymic epithelial tumors according to the World Health Organization (WHO) classification. METHODS: Thirty-three patients (age range, 34-68 y; mean age, 54.6 y) with thymic epithelial tumors, who underwent both integrated PET/CT and enhanced CT, were included. The clinicopathologic stages, maximum standardized uptake values (SUVs), and uptake patterns of tumors on integrated PET/CT images, and various enhanced CT findings, are described according to the simplified (low-risk [types A, AB, and B1] and high-risk [types B2 and B3] thymomas and thymic carcinomas) subgroups of the WHO classification. Discriminant analysis was performed to determine the relative capabilities of integrated PET/CT and enhanced CT findings to differentiate tumor subgroups. RESULTS: Tumors included 8 low-risk thymomas, 9 high-risk thymomas, and 16 thymic carcinomas. The maximum SUVs of high-risk thymomas (P < 0.001) and low-risk thymomas (P < 0.001) were found to be significantly lower than those of thymic carcinomas. Homogeneous 18F-FDG uptake within tumors was more frequently seen in thymic carcinomas than in high-risk thymomas (P = 0.027) or low-risk thymomas (P = 0.001). The uptake pattern (homogeneous vs. heterogeneous) on integrated PET/CT images and the presence of mediastinal fat invasion on enhanced CT images were found to be useful for differentiating tumor subgroups. In addition, integrated PET/CT helped detect lymph node metastases, which were not identified on enhanced CT in 2 patients. CONCLUSION: Integrated PET/CT was found to be useful for differentiating subgroups of thymic epithelial tumors and for staging the extent of the disease.

Adenocarcinoma↗