RESPONSE RATE AND PROGNOSTIC FACTORS OF RECURRENT OLIGODENDROGLIOMA TREATED WITH PROCARBAZINE, CCNU, AND VINCRISTINE CHEMOTHERAPY

Objectives: To determine the response rate and factors correlated with response of oligodendroglial tumors to procarbazine, lomustine (CCNU) , and vincristine (PCV) chemotherapy. Design: Retrospective, observati onal multicenter study. Methods: Patients treated with PCV or intensif ied PCV chemotherapy for a recurrent oligodendroglial tumor after surg ery and radiation therapy with measurable disease were retrospectively evaluated for response. A 50% reduction in cross-sectional enhancing tumor area was considered a partial response. Stabilized or responding patients received six cycles of PCV unless unacceptable toxicity occu rred. Results: Fifty-two patients were included; median time to progre ssion (MTP) for the entire group was 10 months. In 17% of patients a c omplete response (MTP, 25 months) was obtained, and in 46% a partial r esponse (MTP, 12 months) was obtained. Median overall survival was 20 months. Although treatment was discontinued for toxicity in seven pati ents, it was generally well tolerated. The intensified PCV regimen was more toxic. Patients initially presenting with seizures and patients with tumor necrosis in histologic specimens had a better response rate in contrast to patients who had their first relapse within 1 year of first treatment (surgery and radiation therapy). Conclusions: Oligoden droglial tumors are chemosensitive, but most patients will have relaps ed after 12 to 16 months. New studies must aim at improving initial tr eatment and second-line chemotherapy.