Radiotherapy alone versus radiotherapy plus concomitant and post-radiotherapy temozolomide in newly diagnosed anaplastic astrocytoma

Abstract

12523 Background: Malignant gliomas (glioblastoma multiforme and anaplastic astrocytoma) occur more frequently than other types of primary central nervous system tumors, having a combined incidence of 5–8/100,000 population. Even with aggressive treatment using surgery, radiation, and chemotherapy, median reported survival is less than 1 year. Temozolomide, a new drug, has shown promise in treating malignant gliomas. in this study we evaluate the value of adding temozolomide concomitantly with radiotherapy and for 6 cycles after in newly diagnosed anaplastic astrocytoma over radiotherapy alone. Methods: patients with newly diagnosed , histologically confirmed anaplastic astrocytoma were randomly assigned to receive, group A radiation therapy alone ( localized irradiation 60 Gy, fractionated 2 Gy / fraction, 5 fractions / week for 6 weeks) orgroup B radiation therapy alone ( localized irradiation 60 Gy, fractionated 2 Gy / fraction, 5 fractions / week for 6 weeks) plus temozolomide 200 mg per square meter daily for 5 days orally from the 1st day of radiotherapy to be repeated every 28 days for a total of 8 cycles ( 2 during radiotherapy and 6 after). The primary end point were overall survival and safety. Results: A total of 70 patients were randomized , with 35 in each treatment group. Median age was 41 years in group A and 43 years in group B. Surgical resection was complete in 5 % patients,partial resection in 88 % and stereotactic biopsy in 7% patients. In the temozolomide group median survival was 16.7 months and it was only 11.3 months in the radiotherapy alone group. Temozolomide was also associated with a high response rate 62%(CR 8.5% and PR 54.2 %) versus 37% in radiotherapy alone group with minimal additinal toxicity in the temozolomide arm. Conclusions: This randomized phase II trial suggest that temozolomid is effective and add statistically significant survival benefit over radiotherapy alone in newly diagnosed anaplastic astrocytoma with minimal toxicity. No significant financial relationships to disclose.