Multiple radiation sessions reduce recurrence after brain metastasis surgery

A randomized trial has found that focused radiation delivered over three to five sessions, rather than one, reduced cancer recurrence after surgery for large brain metastases. These are tumours formed when cancer spreads to the brain from elsewhere in the body.

The study involved 242 patients who had surgery to remove a large metastasis. They were randomly assigned to receive radiation in one session or several. After one year, 87% of the multi-session group remained free from recurrence at the surgical site, compared with 81% of the single-session group, a statistically significant improvement.

Radiation after surgery targets microscopic cancer cells that may remain. Spreading treatment across several visits gives healthy brain tissue time to recover between doses while allowing an effective dose to reach the treatment area.

Patients in the multi-session group also lived a median of about 29 months, compared with 20 months. Researchers called that difference unexpected and said more work is needed to understand why it occurred. Side effects did not differ significantly between the groups, and researchers observed no difference in quality of life.

The findings, presented at the American Society for Radiation Oncology’s annual meeting, strengthen evidence for using several radiation sessions after surgery for large brain metastases. Additional visits can be burdensome, however, making the balance between treatment time and preventing recurrence important for patients.