Combined treatment modality for anaplastic oligodendroglioma and oligoastrocytoma: a 10-year update of a phase II study.

Abstract

To provide updated outcome data (10 years) of a Phase II study of combined surgery, postoperative radiotherapy, and adjuvant chemotherapy in patients with anaplastic oligodendroglioma and oligoastrocytoma. In 23 adult patients, surgery, postoperative radiotherapy (60 Gy in 30 daily fractions within 6 weeks), and adjuvant modified chemotherapy (procarbazine 60 mg/m(2) on Days 1-14, lomustine 100 mg/m(2) on Day 1, and vincristine 1.4 mg/m(2) [maximum 2 mg] on Days 1 and 8) were administered every 6 weeks for up to six cycles or until progression occurred. The median follow-up was 116 months for all patients. The median survival time was 118 months, and the 5-year and 10-year survival rate was 57% and 47%, respectively. The median time to tumor progression was 78 months, with a 5-year and 10-year progression-free survival rate of 52% and 39%, respectively. Gender, age, Karnofsky performance status, location, and histologic type did not influence survival. Patients with tumors <or=4 cm did better than those with tumors >4 cm (p = 0.0470), as did those with total tumor resection compared with those with subtotal tumor resection or biopsy only (p = 0.0024). Gender, Karnofsky performance status, location, and histologic type did not influence progression-free survival, but younger age (p = 0.0389), smaller tumor size (p = 0.0357), and more radical surgery (p = 0.0033) correlated positively with it. Acute high-grade (Grade 3 or worse) chemotherapy-related toxicity was mainly hematologic, with 3 patients (13%) experiencing acute Grade 4 toxicity. The results of this 10-year update confirmed that the trimodality approach is effective in patients with anaplastic oligodendroglioma and oligoastrocytoma.