IDH1(R132H) Immunoexpression in Glioma

Abstract

Background and objectives: Gliomas are the most common type of primary brain tumors. They result from accumu-- lation of multiple genetic alterations. Isocitrate dehydrogenase 1 mutations are detected in gliomas. This study aimed to assess IDH1 immunoexpression in different types of gliomas and to correlate the results with patient’s age, gender, tumor site, tumor type and grade. Methods:During the period from January 2015 –January 2017, 97 cases of gliomas were collected from Rizgary Teaching Hospital and private laboratories in Erbil city. Typing and grading of tumors were done according to World Health Organization classification of brain tumors 2007.Immunohistochemical staining was done for IDH1 using monoclonal Antibody IDH1R132. Results: Out of 97 cases of gliomas; 16 were grade I, 27 were grade II, 10 were anaplastic gliomas grade III and 44 cases were glioblastomas; grade IV. Positive IDH1 immunoex- pression was observed in 36 (37.1%) cases of gliomas. The highest prevalence of IDH1 was found in the age group 30-44 years (52.8%), in supratentorial tumors (44.3%) and in grade II and III astrocytoma (72.2% and 75%).Highly significant correlation was found between Isocitrate dehydrogenase 1 expression and age of the patients, tumor type and grade while a significant correlation was found between Isocitrate dehydrogenase 1 expression and tumor site. Conclusions:Our study concluded that Isocitrate dehydrogenase 1 is 36 (37.1%) expressed in gliomas and it is sig- nificantly associated with patient’s age, tumor site, histological type and grade, thus it may act as a good diagnostic and prognostic marker for gliomas.