The role of palliative radiotherapy for brain metastases

Brain metastases (BRM) are common complications of malignancy, frequently associated with disability and death. Clinical trials have addressed a few of the issues arising from treatment options for BRM. Phase III trials have shown superior survival for patients with solitary resectable BRM (SRBRM) when palliative radiation treatment (RT) to the brain is preceded by resection compared to brain RT alone, but no trial has explored resection plus brain RT compared to resection alone. One Phase III trial in patients with solitary unresected BRM comparing lower to higher doses of RT has shown a small survival advantage with higher-dose radiotherapy. All other trials, however, comparing different radiation doses and fractionation schedules have failed to indicate improved outcomes from treatment more intense than 2000 cGy in 5 fractions over 1 week (in any subset of patients with unresected BRM). A panel of radiation oncologists and medical oncologists discussed a literature review and results of Phase III trials of therapy for BRM. The panel was instructed to identify from these trials any evidence for the efficacy, indications, toxicity and fractionation of palliative RT for BRM. The panel concluded that unresected BRM is a possible indication for brain RT. The panel concluded that the benefits and toxicities of brain RT for unresected BRM are not characterized adequately to allow a stronger recommendation. The panel concluded that there is no evidence for superiority for any dose or schedule of brain RT for BRM more protracted or intense than 2000 cGy in 5 fractions over one week. The panel recommended further study in order to characterize the benefits and toxicities of brain RT for unresectable BRM. The panel considered the potential value of conducting a Phase III trial comparing palliative care and strategies that included brain RT to the same strategies excluding brain RT; the panel did not, however, reach consensus on the feasibility of such a trial.