Phase II randomized trial of temozolomide and concurrent radiotherapy in patients with brain metastases

To determine the efficacy, tolerability, and safety of concurrent temozolomide and radiotherapy in patients with previously untreated brain metastases.

Fifty-two patients with brain metastases from solid tumors were randomized to oral temozolomide (75 mg/m(2)/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/m(2)/d) for 5 days every 28 days for an additional six cycles. The primary end points were radiologic response and neurologic symptom evaluation.

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 >or= 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.

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.