Department of Pathology and Laboratory Medicine, All India Institute of Medical Science, Rishikesh, Uttarakhand, India.
Department of Internal Medicine, Northeast Ohio Medical University, Canton Medical Education Foundation, Ohio, USA.
J Cancer Res Ther. 2020 Oct-Dec;16(6):1476-1481. doi: 10.4103/jcrt.JCRT_22_17.
Isocitrate dehydrogenase-1 (IDH1) mutation is now an established early event in gliomagenesis. The ability to detect this mutation by several techniques including immunohistochemistry makes it a significant marker for diagnosing and prognosticating gliomas. This study was done to assess the expression of mutant IDH1 in different grades of gliomas and evaluate its utility in differentiating reactive gliosis from glioma and defining surgical margins of these tumors in the operative specimens.
A total of fifty cases including equal number of Grade I, II, III, and IV gliomas and gliosis were included in the study. Formalin-fixed, paraffin-embedded tissue sections from these lesions were immunostained with IDH1 and Ki-67 antibody, and percentage of tumor cells that stained positive with these markers was assessed.
Grades II, III, and IV showed consistent immunopositivity for IDH1. No immunostaining was noted in Grade I glioma and gliosis. Mean Ki-67 labeling index correlated with grades of gliomas with low activity in Grade I and high activity in Grade IV. Individual tumor cells infiltrating into adjacent normal brain parenchyma also stained positive with IDH1 antibody.
Immunostaining for IDH1 mutation can be utilized as a reliable marker in the precise diagnosis of diffuse gliomas and also in objective assessment of surgical margins to differentiate gliomas from gliosis.
异柠檬酸脱氢酶-1（IDH1）突变现在是胶质瘤发生的早期事件。通过包括免疫组织化学在内的几种技术检测到这种突变，使其成为诊断和预测胶质瘤的重要标志物。本研究旨在评估突变型 IDH1 在不同级别胶质瘤中的表达，并评估其在区分反应性神经胶质增生与胶质瘤以及定义这些肿瘤手术切缘方面的效用。
共纳入 50 例病例，包括数量相等的 I 级、II 级、III 级和 IV 级胶质瘤和神经胶质增生。对这些病变的福尔马林固定、石蜡包埋组织切片进行 IDH1 和 Ki-67 抗体免疫染色，并评估这些标记物染色阳性的肿瘤细胞百分比。
II 级、III 级和 IV 级均显示出一致的 IDH1 免疫阳性。I 级胶质瘤和神经胶质增生未见免疫染色。Ki-67 标记指数与胶质瘤的分级相关，I 级活性低，IV 级活性高。浸润到邻近正常脑组织的单个肿瘤细胞也用 IDH1 抗体染色阳性。
IDH1 突变的免疫染色可作为弥漫性胶质瘤精确诊断的可靠标志物，也可用于客观评估手术切缘，以区分胶质瘤与神经胶质增生。
