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

Abstract

Purpose: 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.

Methods and materials: 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.

Results: 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.

Conclusion: The results of this 10-year update confirmed that the trimodality approach is effective in patients with anaplastic oligodendroglioma and oligoastrocytoma.