Phase II Randomized Trial of Temozolomide and Concurrent Radiotherapy in Patients With Brain Metastases

Abstract

PURPOSE: To determine the efficacy, tolerability, and safety of concurrent temozolomide and radiotherapy in patients with previously untreated brain metastases. PATIENTS AND METHODS: Fifty-two patients with brain metastases from solid tumors were randomized to oral temozolomide (75 mg/m2/d) concurrent with 40-Gy fractionated conventional external-beam radiotherapy (2 Gy, 5 d/wk) for 4 weeks versus 40-Gy radiotherapy alone. The group receiving temozolomide and radiotherapy continued temozolomide therapy (200 mg/m2/d) for 5 days every 28 days for an additional six cycles. The primary end points were radiologic response and neurologic symptom evaluation. RESULTS: The objective response rate was significantly (P = .017) improved in patients receiving temozolomide and radiotherapy versus radiotherapy alone. Among 24 patients assessable for response in the temozolomide group, 23 (96%) of 24 responded, including nine (38%) patients with a complete response and 14 (58%) patients with a partial response. With radiotherapy alone, 14 (67%) of 21 assessable patients responded, including seven (33%) complete responses and seven (33%) partial responses. There was marked neurologic improvement in the group receiving temozolomide, and the proportion of patients requiring corticosteroids 2 months after treatment was lower in the temozolomide group compared with radiotherapy alone (67% v 91%, respectively). Daily temozolomide concurrent with radiotherapy was generally well tolerated; however, grade ≥ 2 nausea (48% v 13%, P = .13) and vomiting (32% v 0%, P = .004) were significantly increased in the temozolomide group. Hematologic toxicity was predictable and reversible. CONCLUSION: Temozolomide is safe, and a significant improvement in response rate was observed when administered in combination with radiotherapy in patients with previously untreated brain metastases. A larger randomized trial is warranted to verify these results.