Reiko Nakajima

Clinical role of early dynamic FDG-PET/CT for the evaluation of renal cell carcinoma

ObjectivesWe studied the usefulness of early dynamic (ED) and whole-body (WB) FDG-PET/CT for the evaluation of renal cell carcinoma (RCC).MethodsOne hundred patients with 107 tumours underwent kidney ED and WB FDG-PET/CT. We visually and semiquantitatively evaluated the FDG accumulation in RCCs in the ED and WB phases, and compared the accumulation values with regard to histological type (clear cell carcinoma [CCC] vs. non-clear cell carcinoma [N-CCC]), the TNM stage (high stage [3–4] vs. low stage [1–2]), the Fuhrman grade (high grade [3–4] vs. low grade [1–2]) and presence versus absence of venous (V) and lymphatic (Ly) invasion.ResultsIn the ED phase, visual evaluation revealed no significant differences in FDG accumulation in terms of each item. However, the maximum standardized uptake value and tumour-to-normal tissue ratios were significantly higher in the CCCs compared to the N-CCCs (p < 0.001). In the WB phase, in contrast, significantly higher FDG accumulation (p < 0.001) was found in RCCs with a higher TNM stage, higher Furman grade, and the presence of V and Ly invasion in both the visual and the semiquantitative evaluations.ConclusionsED and WB FDG-PET/CT is a useful tool for the evaluation of RCCs.Key Points• ED and WB FDG-PET/ CT helps to assess patients with RCC• ED FDG-PET/CT enabled differentiation between CCC and N-CCC• FDG accumulation in the WB phase reflects tumour aggressiveness• Management of RCC is improved by ED and WB FDG-PET/CT

Evaluation of renal cell carcinoma histological subtype and fuhrman grade using 18F-fluorodeoxyglucose-positron emission tomography/computed tomography

AbstractObjectivesWe evaluated 18F-fluorodeoxyglucose (FDG) uptake by renal cell carcinomas (RCCs) to determine whether different histological subtypes and Fuhrman grades can be distinguished.MethodsWe retrospectively reviewed the records and maximum standardised uptake value (SUVmax) of 147 patients with 154 RCCs who underwent FDG-positron emission tomography (PET)/computed tomography (CT) prior to tumour resection.ResultsThe SUVmax was significantly lower in chromophobe RCC (chRCC) tumours than in clear cell RCC (ccRCC; p = 0.003) and papillary RCC (pRCC; p = 0.034) tumours. The mean tumour SUVmax was 4.58 ± 4.1 (range, 1.29–30.4) for ccRCC, 3.98 ± 1.9 (range, 0.49–6.72) for pRCC, and 1.93 ± 0.9 (range, 0.89–3.41) for chRCC. The SUVmax was not significantly different between the ccRCC and pRCC groups. In ccRCC and pRCC tumours, high-grade tumours had a significantly greater SUVmax (p < 0.001 and p < 0.05) than low-grade tumours by analysis of variance (ANOVA) and the Mann-Whitney U test. In ccRCC, multivariate regression analysis indicated that the SUVmax was a significant indicator of Fuhrman grade. No significant differences in uptake were observed between high- and low-grade chRCC tumours.ConclusionsThe SUVmax obtained using FDG-PET/CT may be an important indicator for predicting tumour grade in ccRCC and pRCC.Key Points• FDG accumulation reflects tumour aggressiveness and correlates with Fuhrman grade. • FDG-PET/CT enables the differentiation of high- and low-grade ccRCC and pRCCs. • FDG-PET/CT may valuable in the identification of some high-grade RCCs.

Etanercept-induced sarcoidosis in rheumatoid arthritis: FDG PET findings.

We report the F-FDG PET/CT findings of an etanercept-induced sarcoidosis in a patient with rheumatoid arthritis. A 68-year-old woman with rheumatoid arthritis who had been treated with etanercept and methotrexate showed multiple lung nodules and hilar lymph node swellings on CT. She underwent FDG PET/CT for cancer screening. Intense FDG uptakes were found in the multiple lung nodules, bilateral hilar lymph nodes, a periurethral masslike lesion, and cranial meningeal nodules. A histopathological examination revealed epithelioid granuloma with multinucleated giant cells, which was compatible with sarcoidosis.

Pathogenesis and FDG-PET/CT findings of Epstein–Barr virus-related lymphoid neoplasms

Epstein–Barr virus (EBV) is one of the most common viruses, infecting more than 90% of the adult population worldwide. EBV genome is detected in some lymphoid neoplasms. Not only their histopathological subtypes, but also their backgrounds and their clinical courses are variable. A number of B-cell lymphoproliferative disorders associated with the immunocompromised state are related to EBV infection. The incidences of these disorders have been increasing along with generalization of organ transplantations and use of immunosuppressive treatments. Furthermore, some EBV-positive lymphoma can also occur in immunocompetent patients. While evaluating patients with generalized lymphadenopathy of unknown cause by positron emission tomography/computed tomography with 2-deoxy-2-[18F]fluoro-d-glucose (FDG-PET/CT), the possibility of lymphoid neoplasms should be considered in some patients, and a careful review of the background and previous history of the patients is necessary. In this review article, we describe the pathogenesis of EBV-related lymphoid neoplasms and then present FDG-PET/CT images of representative diseases. In addition, we also present a review of other EBV-related diseases, such as infectious mononucleosis and nasopharyngeal carcinoma.

Sclerosing angiomatoid nodular transformation (SANT) of the spleen: a case report with FDG-PET findings and literature review.

We report the 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings of sclerosing angiomatoid nodular transformation (SANT) of the spleen. The patient was a 37-year-old woman with a splenic mass incidentally found on abdominal ultrasound. FDG-PET/CT showed weak FDG accumulation (maximum standardized uptake value = 3.65). An unenhanced CT scan showed a low density and well-circumscribed splenic tumor that demonstrated weak enhancement from the arterial to delayed phase. Although hemangioma or hamartoma of the spleen was preoperatively diagnosed, histopathological examination revealed SANT. Therefore, when a splenic tumor with weak contrast medium enhancement and low FDG accumulation is observed, SANT should be considered as a differential diagnosis. Although CT and magnetic resonance imaging features of SANT have been reported, there are few reports on FDG-PET/CT findings. We report the radiological features of SANT, including FDG-PET/CT, and review the literature on SANT.

Diagnostic Ability of FDG-PET/CT in the Detection of Malignant Pleural Effusion.

Abstract We investigated the role of F-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) for the differential diagnosis of malignant and benign pleural effusion. We studied 36 consecutive patients with histologically proven cancer (excluding malignant mesothelioma) who underwent FDG-PET/CT for suspected malignant pleural effusion. Fourteen patients had cytologically proven malignant pleural effusion and the other 22 patients had either negative cytology or clinical follow-up, which confirmed the benign etiology. We examined the maximum standardized uptake values (SUVmax) of pleural effusion and the target-to-normal tissue ratio (TNR), calculated as the ratio of the pleural effusion SUVmax to the SUVmean of the normal tissues (liver, spleen, 12th thoracic vertebrae [Th12], thoracic aorta, and spinalis muscle). We also examined the size and density (in Hounsfield units) of the pleural effusion and pleural abnormalities on CT images. TNR (Th12) and increased pleural FDG uptake compared to background blood pool were significantly more frequent in cases with malignant pleural effusion (P < 0.05 for both). The cutoff TNR (Th12) value of >0.95 was the most accurate; the sensitivity, specificity, and accuracy for this value were 93%, 68%, and 75%, respectively. FDG-PET/CT can be a useful method for the differential diagnosis of malignant and benign pleural effusion.

11C-methionine PET/CT findings in benign brain disease

Abstract11C-methionine (MET) is one of the most commonly used positron emission tomography (PET) tracers for evaluation of malignant brain tumor, with MET-PET being a sensitive technique for visualization of primary and recurrent malignant brain tumors. However, previous reports have demonstrated MET uptake in lesions associated with benign brain diseases. These diseases usually show an increase in MET uptake similar to that of malignant tumors. This pitfall in MET-PET image interpretation is important not only for nuclear medicine professionals, but also for radiologists. In this review, we demonstrate the imaging characteristics of MET uptake in benign brain disease, and recommend physician interpretation of imaging findings and disease characteristics for optimal patient management. Benign uptake must be identified to prevent misdiagnosis and unnecessary surgical operations.