Background: The optimal treatment of anaplastic gliomas is controversial. Standard of care in most centers is still radiotherapy. This phase III study compared the efficacy and safety of radiotherapy vs chemotherapy in patients (pts) with newly-diagnosed, supratentorial gliomas of WHO grade III.

Methods: Pts were randomized 2:1:1 between June 1999 and February 2005 in 34 German centers to receive (i) a 6-week course of radiotherapy (1,8-2 Gy fractions, total dose 54-60 Gy) or (ii) four 6-week cycles of CCNU at 110 mg mg/m2 on day 1, vincristine at 2 mg on days 8 and 29 and procarbazine at 60 mg/m2 on days 8-21 or eight 4-week cycles of 200 mg/m2 temozolomide on days 1-5. Treatment was stopped prematurely at disease progression or occurrence of unacceptable toxicity. At this time or at disease progression, treatment in the radiotherapy group was continued with one of the chemotherapies (1:1 randomization) and with radiotherapy in both chemotherapy groups. The primary endpoint was time-to-treatment-failure (TTF) defined as progression after radiotherapy and one chemotherapy in either sequence, or any time before if further therapy could not be employed. Assuming a 50% improvement in TTF of starting with chemotherapy, 318 pts were to be enrolled to provide 80% power to achieve statistical significance at a one-sided level of 0.05.