Epidemiology of glial tumors of brain according to the WHO classification 2016: A 10-year study

Introduction: Central nervous system (CNS) tumors consist of two broad groups, glial and non-glial. Glial neoplasms, the most common primary intracranial tumors,constitute a group of aggressive cancer derived from astrocytes, ependymal cells, oligodendrocytes and mixed glial cells, with high morbidity and mortality rates. Eachentity is characterized by heterogeneity that makes variability in the etiology, morphology, clinical behavior, histopathological classification, prognosis, diagnosis, outcome, treatment, etc. The purpose of this study was to extend our information of the glial tumor epidemiology. Methods: It was a retrospective study of 80 paraffin embedded blocks of glial specimens recorded in Vali-Asr Hospital, Arak, Iran from 2006 to 2015 (with follow up at December 2016). We re-analyzed the incidence of them by tumor grades(according to the last WHO classification-2016), gender, age, size and anatomical localization. Results: The incidence of glial tumors consists of 10 pilocystic, 12 diffuse, 9anaplastic astrocytomas, 35 glioblastoma multiform (GBM), 3 grade I and II, 6 anaplastic ependymomas, 2 subependymomas, 1 ependymoblastoma and 2 anaplastic oligodendrocytomas. The male:female ratio was calculated 3:1. Conclusion: The majority of the cases were GBM (35 cases), and the mean age of the patients was 43.36±21.79 years. The most frequent location of tumors was frontal lobe followed by the temporal, parietal, frontoparietal, temporoparietal, parietooccipital lobe and spinal cord. This gliomas registry study provides essential information that could develop glial management and healthcare practice.

Epidemiology of glial tumors of brain according to the WHO classification 2016: A 10-year study Keywords:

epidemiology , glioma , glial tumor , astrocytoma , ependymoma , oligodendrocytoma , pathology , central nervous system , brain