Results of a clinical trial with polychemotherapy of anaplastic oligodendrogliomas

Introduction: Anaplastic gliomas are incurable tumors. The subgroup of anaplastic oligodendrogliomas seem to be chemosensitive tumors, so that an adjuvant nitrosourea-based chemotherapy was proposed in 1992 by Cairncross et al. In a clinical trial, we tried to evaluate the hypothesis that these tumours are indeed chemosensitive. Patients and Methods: In the last two years, seven patients with anaplastic oligodendrogliomas WHO III agreed to a postoperative adjuvant chemotherapy trial. Five of them were treated according to the above regimen with BCNU, vincristine and procarbazine. Two patients received an individualized therapy regimen depending on the rsults of in-vitro-chemosensitivity-testing. The full chemotherapy schedule consisted of 12 cycles with an interval of four to six weeks. Every four months or in cases of a suspected tumor progression, CT, MRI as well as IMT-SPECT to monitor for biological activity were performed to define the therapy state. Chemotherapy was stopped in cases of progression and patients were either irradiated or reoperated if possible. Results: All patients treated with BCNU, vincristine and procarbazine showed tumor progression under chemotherapy. One patient died 8 months after surgery, 4 patients (80%) were reoperated with the neuropathologically proven diagnosis of a secondary glioblastoma. In the individualized group, both patients completed chemotherapy in complete remission without any tumor 27 and 17 months after surgery. Discussion and conclusions: In contrast to the actual neurooncological literature, anaplastic oligodendrogliomas seem to be not primarily chemosensitive.