Factors possibly influencing the prognosis of oligodendroglioma.

Fifty-seven cases of oligodendroglioma (including eight cases of malignant oligodendroglioma) treated at the University of Tokyo Hospital between 1961 and 1985 were analyzed for factors influencing the survival rate. Factors related to a poor outcome were findings of malignancy and symptoms of dementia. Survival rate and postoperative survival period were not influenced significantly by radiation therapy, extent of resection, tumor characteristics, or ABO blood groups.