Tanycytes are specialized form of ependymal cells chiefly found in the third ventricle (infundibular recess), and have processes extending into the hypothalamus. Histomorphologic and ultrastructural characteristics similar to tanycyte has been reported in several brain tumors, including tanycytic ependymoma, astroblastoma, chordoid glioma, pilomyxoid astrocytoma, and subependymoma. This article briefly reviews these brain tumors from the standpoint of tanycytic differentiation.

The use of some different positron emission tomography (PET) imaging agents is expected to lead the useful way for applications toward efficient malignancy grading and diagnosis of brain tumors. In this study, the usefulness of ¹⁸ F-fluorodeoxyglucose (FDG), ¹¹ C-methionine (MET), ¹⁸ F-fluoro-3’-deoxy-3’-L-fluorothymidine (FLT) and ¹⁸ F-fluoromisonidazole (FMISO) PET images was retrospectively reviewed. In malignant lymphomas, tumor FDG uptake was significantly higher with accelerated phosphorylation activity compared with that observed in the normal cortex. PET studies using MET and FLT are useful for tumor detection in gliomas. MET transport may be increased by an increased number of microvessels combined with a higher density or activity of LAT1 in the tumor endothelial cells in high-grade gliomas. FLT uptake in the tumor is also significantly related to transport through the disrupted BBB, but not through phosphorylation activity. The viable hypoxic tissue assessed by FMISO PET was related to the neovascularization in glioblastomas. FMISO PET appears to be a suitable biomarker for predicting a highly malignant tumor in patients with glioma. PET imaging is a noninvasive modality that is useful in management of brain tumors.

Gliomas have been diagnosed according to the histological classification published by the World Health Organization (WHO). However, recent advance in tumor genetics validated clinical value of genetic analysis in glioma management, and genetic classification is considered to have advantage to histological classification in predicting the patients’ outcome. In 2016, WHO revised classification of tumors of the central nervous system, and remarkable revision was made in various tumors. Of them, classification of diffuse glioma of lower grade was advanced in practical manner. Those tumors are classified by key genetic aberrations including mutation of isocitrate dehydrogenase 1/2 gene (IDH1/2) and codeletion of chromosomal arms 1p and 19q. Mutation in TP53, ATRX and promoter of TERT are helpful in subgrouping the tumors.

In this review, biological aspects of genetic aberrations applied to 2016 WHO classification are discussed to help understanding of oncology in relation with management for grade II-III diffuse gliomas.

The first Tokyo brain tumor meeting was held in 1980, and 36 years passed now.The author is assigned the secretariat of the Tokyo brain tumor meeting by 2007 and makes an effort for theadministration of the main meeting in spite of being poor ability as a representative organizer now.I report process and the present conditions that 30 years pass, and came to reach the 119th from breeding ofthis Tokyo brain tumor meeting afterwards this time.