Proton Stereotactic Radiosurgery for Brain Metastases: A Single-Institution Analysis of 370 Patients.

To the best of our knowledge, this is the first reported series of proton SRS for the management of brain metastases. Moderate-dose proton SRS is well tolerated and can achieve good local control outcomes, comparable to those obtained with conventional photon SRS strategies. Although proton SRS remains resource-intensive, future strategies evaluating its selective utility in patients who would benefit most from integral dose reduction should be explored.