Grading of oligodendrogliomas

Abstract

The purpose of this study was to determine the effectiveness of histologic grading of oligodendrogliomas in a retrospective study. 323 cases with adequate clinical information and confirmatory histological material were acquired from the files of the AFIP. A grading system was devised using the following criteria: endothelial proliferation, necrosis, nuclear/cytoplasmic ratio, cell density and pleomorphism. The grading system separated 23% of the cases into grade A, 49% into grade B, 22% into grade C and 6% into grade D. Statistical analysis showed that the grading system significantly correlated with survival (P ⩽ 0.01). Median survival periods for each grade were as follows: grade A, 94 months; grade B, 51 months; grade C, 45 months; grade D, 17 months. Of the five factors comprising grade, only pleomorphism was significantly correlated with survival by itself (P ⩽ 0.01). It is concluded that grading of this form of glioma can be an effective estimate of prognosis. Cancer 52:2107‐2114, 1983. Copyright © 1983 American Cancer Society