Survey of malignant pleural mesothelioma treatment in Japan: Patterns of practice and clinical outcomes in tomotherapy facilities.

We conducted a nationwide survey of tomotherapy for malignant pleural mesothelioma (MPM) in Japan. Fifty-six facilities were surveyed and data on 31 patients treated curatively between 2008 and 2017 were collected from 14 facilities. Twenty patients received hemithorax irradiation after extrapleural pneumonectomy (EPP) (first group). Five patients received irradiation without EPP (second group), while six received salvage radiotherapy for local recurrence (salvage group). Among the seven patients not undergoing EPP, five (four in the second group and one in the salvage group) were treated with lung sparing pleural irradiation (LSPI) and two with irradiation to visible tumors. Two-year overall survival (OS) rates in the first and second groups were 33% and 60%, respectively (median, 13 vs 30 months, P = 0.82). In the first and second groups, 2-year local control (LC) rates were 53 and 67%, respectively (P = 0.54) and 2-year progression-free survival (PFS) rates were 16% and 60%, respectively (P = 0.07). Distant metastases occurred in 15 patients in the first group and three in the second group. In the salvage group, the median OS was 18 months. Recurrence was observed in the irradiated volume in four patients. The contralateral lung dose was higher in LSPI than in hemithorax irradiation plans (mean, 11.0 ± 2.2 vs 6.1 ± 3.1 Gy, P = 0.002). Grade 3 or 5 lung toxicity was observed in two patients receiving EPP and hemithorax irradiation, but not in those undergoing LSPI. In conclusion, outcomes of EPP and hemithorax irradiation were not satisfactory, whereas LSPI appeared promising and encouraging.

Determinants of extraaortic arterial 18F-FDG accumulation in asymptomatic cohorts: sex differences in the association with cardiovascular risk factors and coronary artery stenosis.

UNLABELLED: The objective of this study was to evaluate extraaortic arterial (18)F-FDG accumulation in asymptomatic cohorts by sex and to clarify the association between extraaortic arterial (18)F-FDG accumulation and cardiovascular risk factors (CRFs) and coronary artery stenosis (CAS). METHODS: Five hundred twenty-one asymptomatic individuals (351 men and 170 women) who underwent cancer and CAS screening were enrolled. We evaluated extraaortic arterial (18)F-FDG accumulation in the carotid artery (CA) and iliofemoral artery (IFA) and classified the accumulation patterns into 3 types. Type 1 patients had no extraaortic arterial (18)F-FDG accumulation, type 2 had accumulation in either the CA or the IFA, and type 3 had accumulation in both the CA and IFA. CRFs (age, low-density lipoprotein [LDL] and high-density lipoprotein [HDL] cholesterol, triglyceride concentration, visceral abdominal fat, hypertension, diabetes, and smoking) and significant CAS were examined in relation to each accumulation type. RESULTS: The men showed more extensive extraaortic arterial (18)F-FDG accumulation than the women. Type 3 accumulation (60.4% vs. 37.1%, P < 0.0001) was more frequently observed in men, whereas type 2 (34.2% vs. 44.7%, P = 0.02) and type 1 (5.4% vs. 18.2%, P < 0.0001) accumulation were more frequent in women. The CRFs other than smoking tended to be worse with extensive extraaortic arterial (18)F-FDG accumulation. A multivariate logistic regression analysis showed that hypertension, age, LDL cholesterol, triglyceride, and visceral abdominal fat were significantly associated with type 3 accumulation in men, and LDL cholesterol and HDL cholesterol (inversely) were significantly associated with type 3 accumulation in women. CAS was found in 4.2% (9/212) of male patients and in 1.6% (1/63) of female patients with type 3 accumulation, whereas no CAS was found in the other 2 types. CONCLUSION: The men showed more extensive extraaortic arterial (18)F-FDG accumulation than the women. LDL cholesterol was associated with extensive extraaortic arterial (18)F-FDG accumulation in both sexes, but the other CRFs associated with extensive extraaortic (18)F-FDG arterial accumulation differed between the sexes. The type 3 accumulation was considered to pose a risk of CAS, especially in male patients, whereas non-type 3 accumulation presented little risk.

Assessment of FDG retention differences between the FDG-avid benign pulmonary lesion and primary lung cancer using dual-time-point FDG-PET imaging.

PURPOSE: The aim of this study was to clarify FDG retention differences between FDG-avid benign pulmonary lesions (BPLs) and primary lung cancers (PLCs), and between tuberculous and non-tuberculous BPLs using dual-time-point FDG-PET imaging. METHODS: Thirty-four BPLs and 47 PLCs with a maximal standardized uptake value (SUVmax) >2.5 and a maximal axial diameter >10 mm were enrolled. We compared the retention index (RI) among different types of lesions, and evaluated the relationship between RI and SUVmax at 1 h (SUV1). Glucose transporter-1 (Glut-1) and hexokinase (HK)-2 expression was assessed in eight non-tuberculous BPLs. RESULTS: BPLs and PLCs showed similar high RIs (mean ± SD 33.6 ± 22.6 and 32.5 ± 23.7, respectively; p = 0.95). In BPLs, both tuberculous and non-tuberculous lesions showed high RIs (39.1 ± 25.8 and 30.3 ± 20.3, respectively; p = 0.43). However, BPLs and PLCs exhibited a different relationship between RI and SUV1. BPLs tended to show lower RIs with higher SUV1s, and a mild negative correlation, whereas PLCs showed persistent high RIs and no significant correlation. Glut-1 and HK-2 expression was found in 75 and 12.5 % of non-tuberculous BPLs, respectively. CONCLUSIONS: FDG-avid BPLs could show high RIs regardless of their being tuberculous and non-tuberculous lesions, and no significant difference with PLC RIs was found. FDG-avid BPLs and PLCs showed different relationships between RI and SUV1, and it seemed to be related with different mechanisms of high FDG retention. However, the mechanisms of high FDG retention in FDG-avid BPLs remain unclear, and this matter requires further investigation.

FDG-PET/CT findings of peritoneal lymphomatosis.

Peritoneal lymphomatosis (PL) is an extensive lymphomatous infiltration of the intraperitoneal portion of the subperitoneal space, which is a rare presentation of lymphoma. Using CT or MRI findings alone, it is difficult to differentiate between lymphomatosis, carcinomatosis, and other pathological entities.We experienced two PL cases and herein report the FDG-PET/CT findings. High FDG uptakes were found in omental and peritoneal infiltration, gastric wall involvement, and lymph node involvement in the epiphrenic region, although retroperitoneal lymph node involvement was absent. Systemic abnormal FDG uptakes suggested PL rather than carcinomatosis, and FDG-PET/CT findings were useful for the diagnoses.

A case of diffuse-type primary hepatic lymphoma mimicking diffuse hepatocellular carcinoma.

Primary hepatic lymphoma (PHL) is a very rare disease, especially in the diffuse type. We report a case of a middle-aged man with hepatitis C virus infection who developed diffuse-type PHL mimicking diffuse hepatocellular carcinoma (HCC). Contrast-enhanced computed tomography (CT) and magnetic resonance imaging showed diffusely infiltrated hypovascular lesions throughout the liver, but no intrahepatic portal venous thrombus was observed. Diffusion-weighted imaging and (18)F-FDG positron emission tomography/CT, respectively, showed a very low apparent diffusion coefficient value and high FDG uptake. These findings were more suggestive of diffuse-type PHL than diffuse HCC. Liver biopsy examination confirmed a diagnosis of diffuse large B-cell lymphoma. Systemic staging revealed no evidence of nodal or bone marrow involvement, so PHL was diagnosed. The patient was treated with chemotherapy and achieved complete remission. We suggest that a combination of image modalities may enable differentiation of diffuse-type PHL from diffuse HCC.

Chest wall and axillary lymph node FDG uptake associated with cancer vaccine therapy for lung cancer.

Cancer vaccines are now undergoing clinical investigations, and clinical trials of therapeutic cancer vaccines have been conducted mainly for advanced cancer patients. We experienced 2 cases of multifocal F-18 fluoro-2-deoxy-D-glucose uptake in the chest wall and axillary lymph nodes associated with personalized peptide vaccine therapy for recurrent lung cancer. In this article, we report fluoro-2-deoxy-D-glucose -positron emission tomography and positron emission tomography/computed tomography findings.

Comparison of diffusion-weighted MRI and 2-[fluorine-18]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) for detecting primary colorectal cancer and regional lymph node metastases.

PURPOSE: To examine the usefulness of diffusion-weighted MRI (DW-MRI) for the detection of both primary colorectal cancer and regional lymph node metastases, and compare its performance with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in the same patients. MATERIALS AND METHODS: We studied 25 patients with known colorectal cancer. All underwent both DW-MRI and FDG-PET studies. The images were retrospectively assessed by visual inspection and the imaging findings were compared with histopathological findings on surgical specimens. RESULTS: Of the 27 primary colorectal lesions surgically excised in 25 patients, 23 (85.2%) were true-positive on both DW-MRI and FDG-PET. Two cancers were false-negative on DW-MRI but true-positive on FDG-PET, and two were false-negative on both DW-MRI and FDG-PET. With respect to the detectability of metastatic lymph nodes, DW-MRI and FDG-PET manifested a sensitivity of 80% (8/10) and 30.0% (3/10), a specificity of 76.9% (10/13) and 100% (13/13), and an accuracy of 78.3% (18/23) and 69.6% (16/23), respectively. CONCLUSION: DW-MRI is inferior to FDG-PET for the detection of primary lesions, but superior for the detection of lymph node metastases.

The detection rates and tumor clinical/pathological stages of whole-body FDG-PET cancer screening.

OBJECTIVE: FDG-PET has been used for cancer screening, mainly in East-Asia, and cancers are found not infrequently. However, their stages have not been clarified. We examined the detection rates of various cancers using whole-body PET for the screening of cancers in asymptomatic individuals, focusing on their clinical and pathological stages. METHODS: Whole-body PET was obtained as a part of our cancer screening program among 3,426 healthy subjects. All subjects participated in a course of PET examination in conjunction with conventional examinations including a medical questionnaire, tumor markers, immunological fecal occult blood test, neck and abdominal ultrasonography and whole body computed tomography. A diagnosis and staging was obtained by an analysis of the pathological findings or by an analysis of the clinical follow-up data. RESULTS: Malignant tumors were discovered in 65 lesions found in 3,426 participants (1.90%). The PET findings were true-positive in 46 of the 65 cancer cases. The cancers were found in the following organs: the colon 14; thyroid gland 10; stomach 7; lung 5; liver 3; breast 2; and one each in the kidney, gallbladder, esophagus, pancreas and retroperitoneum. The stages were as follows: stage 0 5, stage I 17, stage II 10, stage III 7, and stage IV 6. One was an unknown primary. There were 19 false-negative findings (0.6%) on PET. Six cancers (0.18%) were missed in our screening program. CONCLUSIONS: PET imaging has the potential to detect a wide variety of cancers at potentially curative stages. Most PET-negative cancers are early stage cancers, and thus can be detected using other conventional examinations such as endoscopy.