Objective: The role of chemotherapy in the treatment of low-grade oligodendrogliomas and oligoastrocytomas is still unclear. A Phase II study was conducted to determine the benefits and toxicity of the procarbazine, lomustine, and vincristine (PCV) regimen in patients with low-grade oligodendrogliomas and oligoastrocytomas recurrent after surgery alone or surgery with radiotherapy.
Methods: Patients with both enhancing and nonenhancing tumors were treated with up to six cycles of standard PCV, and response was evaluated by conventional criteria based on computed tomography or magnetic resonance imaging.
Results: Sixteen of 26 patients (62%) responded to PCV: 3 (12%) experienced complete response, 13 (50%) experienced partial response, 8 (31%) had stable disease, and 2 (8%) had progressive disease. All symptomatic patients who responded and three with stable disease improved in seizure frequency, lateralizing signs, and symptoms of intracranial hypertension. The response rate for patients with enhancing lesions revealed by computed tomography or magnetic resonance imaging (74%) was significantly higher than that of patients with nonenhancing lesions (29%) (P < 0.05). Both oligodendrogliomas and oligoastrocytomas responded to PCV, with complete responses occurring in association with pure tumors only. The median time to tumor progression of all 26 patients was 24 months and was significantly longer for those with oligodendrogliomas compared with those with oligoastrocytomas (32 versus 12 mo) (P < 0.001). Chemotherapy was well tolerated, with mild hematological toxicity and rare skin rashes being the most frequent sequelae.
Conclusion: These results suggest that chemotherapy with PCV is effective in the treatment of recurrent low-grade oligodendrogliomas and oligoastrocytomas.