PROLIFERATING CELL NUCLEAR ANTIGEN AND KI-67 IMMUNOHISTOCHEMISTRY OF OLIGODENDROGLIOMAS WITH SPECIAL REFERENCE TO PROGNOSIS

Background. The biologic behavior of oligodendrogliomas is somewhat un predictable. A supplementary prognostic factor is, therefore, desirabl e. Methods. Thirty-two pure supratentorial oligodendrogliomas were inv estigated using proliferating cell nuclear antigen (PCNA) and Ki-67 im munohistochemical analyses. The correlation of PCNA and Ki-67 labeling index (LI) with prognosis were studied, and the correlation of LI wit h clinical data was evaluated. Results. The PCNA LI had a range of 0-1 7% (mean, 5.27%; standard deviation [SD] = 4.65), and the Ki-67 LI had a range of 0-29% (mean, 4.19%; SD = 5.66). In general, the PCNA LI se emed to be higher than the Ki-67 LI. The mean survival time was 4.4 ye ars, and 5- and 10-year survival rates were 38% and 19%, respectively. Ki-67 and PCNA staining indicated that patients with a high LI (>3% a nd >4%, respectively) had a significantly higher mortality, with mean survival time of 23.5 months and 26.2 months, respectively. No signifi cant correlation between LI (or survival) and tumor size, cerebral loc alization, radiation, resection/biopsy, sex, age, or cytologic atypia was found. Conclusions. The use of Ki-67 and PCNA LI higher than 3% an d 4%, respectively, appears reliable as prognostic factors when invest igating pure supratentorial oligodendrogliomas.