Positron emission tomography/computed tomography (PET/CT) has dramatically altered the landscape of noninvasive glioma evaluation, offering complementary insights to those gained through magnetic resonance imaging (MRI). PET/CT scans enable a multifaceted analysis of glioma biology, supporting clinical applications from grading and differential diagnosis to mapping the full extent of tumors and planning subsequent treatments and evaluations. With a broad array of specialized radiotracers, researchers and clinicians can now probe various biological characteristics of gliomas, such as glucose utilization, cellular proliferation, oxygen deficiency, amino acid trafficking, and reactive astrogliosis. This review aims to provide a recent update on the application of versatile PET/CT radiotracers in glioma research and clinical practice.

Purpose: We aimed to compare different reference regions and select one with the most clinical relevance on C11-acetate (ACE) positron emission tomography/computed tomography (PET/CT) in patients with cerebral glioma. Methods: We retrospectively reviewed 51 patients with cerebral glioma who underwent baseline ACE PET/CT at diagnosis.Other than the standardized uptake value (SUV) of the primary tumor, SUVs of the reference regions including the normal gray matter, white matter, choroid plexus, and cerebellum were measured. Then, the SUV ratio (SUVR = tumor SUV max /reference region SUV mean ) was calculated. The effect of patient age on the SUV mean of each reference was examined and the SUVRs of each reference region were compared between grades. age, sex, tumor size, histological grades, SUVR , and the presence of isocitrate dehydrogenase (IDH) mutation were included for survival analyses. Results: Except for the cerebellum showing a mild negative correlation, we found no correlations between age and SUV mean using the gray matter, white matter, and choroid plexus (r = − 0.280, P < = 0.047). Only the SUVR -choroid plexus was able to differentiate between the WHO grades (Grade II vs. III, P < = 0.035; grade III vs. IV, P < < 0.001; grade II vs. IV, P < 0.001). Multivariate Cox proportional hazards models found that the SUVR-choroid plexus and IDH mutation were statistically significant for predicting OS. Conclusion Of the different reference regions used for grading cerebral gliomas, the choroid plexus was found to be the most optimal.In addition, the SUV ratio is useful to predict the overall survival in the model with the choroid plexus as a reference region.

Purpose: We assessed prognostic implication of bone marrow uptake on baseline F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in patients with advanced-stage diffuse large B-cell lymphoma (DLBCL). Methods: We retrospectively reviewed 140 patients with stage III and IV DLBCL, who underwent baseline F-18 FDG PET/CT at diagnosis. Bone marrow uptake on F-18 FDG PET/CT (BM FDG) was compared with findings on bone marrow biopsy (BMB), and patients were grouped based on these results: BMB-positive and BM FDG-positive (group 1), BMB-positive and BM FDG-negative (group 2), BMB-negative and BM FDG-positive (group 3), and BMB-negative and BM FDG-negative (group 4). The prognostic value of clinicopathologic factors and BM FDG for predicting progression-free survival (PFS) and overall survival (OS) was assessed using a Cox proportional hazards model. Differences in PFS and OS were examined by the Kaplan-Meier method. Results: BMB was the only significant indicator in predicting PFS, and age, IPI score higher than 3, and BM FDG significantly predicted OS. Group 1 showed inferior PFS than group 2 (median PFS, 7.4 vs. 13.9 months; p = 0.04). In contrast, there was no significant difference either in PFS or OS between group 2 and group 3. Conclusion We showed that BM FDG-positive predicted a poorer survival in patients with advanced stage DBLCL. We also found that BMB-negative and BM FDG-positive patients had similar PFS or OS to BMB-positive and BM FDG-negative patients. Further study in a larger population is needed to clarify clinical significance of BM FDG in these patients.

A renal oncocytoma was diagnosed in an 8-year-old female Maltese dog with a history of renal cysts. Tumor cells were not detected until six months after observation of renal cysts. Nephrectomy was performed to treat the neoplasia. Tumor-like masses with numerous nodules were observed in the inner surface of cysts present in the caudal part of the left kidney. Histologically, the tumor consisted of cells with abundant eosinophilic cytoplasm. The diagnosis was based on histological features, periodic acid-Schiff reaction, and immunohistochemical cytokeratin staining. Based on a literature review, this is the first canine renal oncocytoma case reported in Korea.
Adenoma, Oxyphilic ; Animals ; Child ; Cytoplasm ; Diagnosis ; Dogs ; Eosinophils ; Female ; Humans ; Keratins ; Kidney ; Korea ; Nephrectomy ; Periodic Acid-Schiff Reaction

A renal oncocytoma was diagnosed in an 8-year-old female Maltese dog with a history of renal cysts. Tumor cells were not detected until six months after observation of renal cysts. Nephrectomy was performed to treat the neoplasia. Tumor-like masses with numerous nodules were observed in the inner surface of cysts present in the caudal part of the left kidney. Histologically, the tumor consisted of cells with abundant eosinophilic cytoplasm. The diagnosis was based on histological features, periodic acid-Schiff reaction, and immunohistochemical cytokeratin staining. Based on a literature review, this is the first canine renal oncocytoma case reported in Korea.