Who gains from repeat radiosurgery for progressive previously treated brain metastases?—a case series

Background: Characterization of potential beneficiaries from repeat radiosurgery (RRS) for progressive previously treated brain metastases (PPT-BRM) has not received much attention, perhaps because many patients with BRM die following salvage radiosurgery. These individuals remain at risk for neurological deterioration when BRMs are left untreated. Methods: We attempted to study the advantaged people from our four patients and 531 patients identified in a literature search who were treated with RRS for PPT-BRMs. Results: The 2% incidence rate of PPT-BRM from our institution was lower than rates in previous reports (range, 4–25%). The overall efficacy and minimal morbidty associated with RRS have consistently been demonstrated. Even though RRS for PPT-BRM is believed to be essential in patients with good functional status, descriptions of people who benefitted from RRS are poorly documented. Conclusions: RRS for PPT-BRM, generally efficacious, is associated with a low toxicity profile. It is vital that there is careful patient selection for RRS of PPT-BRM given the overall dismal outlook and the potential serious effect of neglected beneficial treatment as well as the intervention-related radionecrosis on the quality of remaining life. Based on the available evidence, we advocate the continued but cautious use of salvage RRS in these people. More research is needed about the patients gaining benefit from the re-irradiation.