Outcomes after whole brain reirradiation in patients with brain metastases

Abstract

Purpose: Patients with brain metastases are often treated with whole brain radiation therapy (WBRT) for purposes of palliation. The treatment of those who experience subsequent intracranial disease progression can include a second course of WBRT, although there is controversy surrounding its safety and efficacy. This study examines the outcomes in patients at Massachusetts General Hospital who underwent reirradiation.

Patients and methods: We examined the medical records of 17 patients at Massachusetts General Hospital with brain metastases who were initially treated with WBRT between 2002 and 2008 and were subsequently retreated with a second course of WBRT. The median dose for the first course of WBRT was 35 Gy (range, 28-40 Gy), with a fraction size of 2 to 3 Gy (median, 2.5 Gy). The median dose at reirradiation was 21.6 Gy (range, 14-30 Gy), with a fraction size of 1.5 to 2 Gy (median, 1.8 Gy).

Results: The second course of WBRT was administered upon radiographic disease progression in all patients. Of 10 patients with complete follow-up data, 8 patients experienced complete or partial symptom resolution, and 2 did not show clinical improvement. The time to radiographic progression was 5.2 months. The median overall survival for all patients after diagnosis of metastases was 24.7 months. The median survival time after initiation of reirradiation was 5.2 months (95% CI, 1.3-8.7). In 6 patients with stable extracranial disease, the median survival time after retreatment was 19.8 months (95% CI, 2.7-∞), compared with 2.5 months (95% CI, 0.8-5.5) for those with extracranial disease progression (p = 0.05). Acute adverse reactions occurred in 70.5% of patients but were mild to moderate in severity.

Conclusion: In select patients and especially those with stable extracranial disease, reirradiation may be an appropriate and effective intervention to provide symptomatic relief and slow intracranial disease progression. Side effects were minimal and did not cause substantial changes in quality of life.