Abstract
Introduction Gliomas are common primary brain tumors. Immunohistochemical components, such as isocitrate dehydrogenase (IDH) mutations, GFAP (glial fibrillary acidic protein), ATRX (alpha-thalassemia/mental retardation, X-linked), and Ki-67, play a pivotal role in glioma diagnostic classification and risk stratification in prior literature. This study aimed to evaluate the association of IDH1 (R132H) IHC as a surrogate marker within the World Health Organization (WHO) integrated framework and to correlate the expression of IDH1 (R132H) with clinicopathological parameters in gliomas. Methods A hospital-based cross-sectional study was conducted on 30 histologically confirmed glioma cases, with an age range from 1 to 70 years. Clinicopathological parameters such as age of the patient, gender, tumor location, histological type, and World Health Organization tumor grade were recorded. Immunohistochemistry for IDH1 (R132H), Ki-67, GFAP, and ATRX was performed. Associations were assessed using Fisher's exact test (2×2 tables) and Fisher-Freeman-Halton exact test (r×c tables), with p < 0.05 considered significant. Results IDH1 (R132H) immunopositivity was seen in 19 cases (63.3%). ATRX retention was observed in 63.3% of cases, GFAP positivity in 93.3%, and a high Ki-67 index in 50% of cases. IDH1 (R132H) IHC status showed a statistically significant association with age, histological type, and WHO grade. No statistically significant association was observed with gender, ATRX, GFAP, or Ki-67 expression. Conclusion IDH1 (R132H) immunohistochemical expression showed a significant association with established clinicopathological indicators, including patient age, histological type, and WHO tumor grade. In this hospital-based cross-sectional study, IDH1 (R132H) IHC-negative status was more frequently observed in higher-grade tumors. These findings support the use of immunohistochemistry as an accessible adjunct in glioma diagnosis and clinicopathological stratification; outcome-based prognostic significance requires longitudinal follow-up.