Effective chemotherapy using PCV (procarbazine, lomustine and vincristine) has been documented in anaplastic oligodendrogliomas and oligoastrocytomas. A pilot study using PCV was conducted for relapsing patients with anaplastic oligodendrogliomas and oligoastrocytomas. Preliminary results are reported. Fourteen patients were enrolled. All received at least two courses of PCV and were evaluable for response. Eleven patients (78%) responded to chemotherapy with complete responses in 2 patients. Response was more obvious regarding contrast enhanced areas than volumes changes (11 responses versus 7). A story of seizure was the main clinical prognostic factor for response. All toxicities were manageable and no treatment related death occurred. Chemotherapy is an effective treatment in aggressive oligodendrogliomas. Further studies must assess the role of chemotherapy in the multidisciplinary management of oligodendroglioma.