Background: Patients with brain metastases who have a favorable survival prognosis may benefit from intensive treatments, including neurosurgery and radiosurgery. However, many patients cannot receive such treatments, and whole-brain radiotherapy (WBRT) alone is their only option. The most common WBRT schedule is 30 grays (Gy) in 10 fractions. In this retrospective study, the authors investigated whether these patients benefit from a dose escalation beyond 30 Gy.
Methods: Data from 109 patients who received 30 Gy in 10 fractions were compared with 75 patients who received 40 Gy in 20 fractions. All patients had a favorable survival prognosis. Both groups were compared for local control (LC) and overall survival (OS). Subgroup analyses were performed for patients who had less radiosensitive tumors (N = 27) and for other patients (N = 157).
Results: The LC rate at 1 year was 28% after 30 Gy and 44% after 40 Gy (P = .064). On multivariate analysis, the 40 Gy dose was associated with improved LC (P = .047). The survival rate at 1 year was 50% after 30 Gy and 61% after 40 Gy (P = .007). On multivariate analysis, the 40 Gy dose was associated with improved OS (P = .008). On subgroup analysis of patients who had less radiosensitive tumors, the 1-year LC rate was 7% after 30 Gy and 38% after 40 Gy (P = .031); and the 1-year OS rate was 40% and 73%, respectively (P = .008). On subgroup analysis of patients who had other tumor types, the 1-year LC rate was 31% after 30 Gy and 45% after 40 Gy (P = .26); and the 1-year OS rate was 52% and 59%, respectively (P = .08).
Conclusions: Escalation of the WBRT dose beyond 30 Gy resulted in better outcomes, particularly for patients who had less radiosensitive tumors.
Copyright © 2011 American Cancer Society.