When patients with ES-SCLC develop brain only progression, should they switch systemic therapy along with brain radiation? This multicenter cohort study included 889 patients with ES-SCLC of whom 203 (22.8%) developed brain only progression on first line systemic therapy. They then received one of three different treatment strategies: continuation of first line therapy with brain RT, switching to a different systemic therapy with brain RT, or switching to a different systemic therapy without any brain RT. Among these, continuing the original radiation along with brain RT was associated with superior overall survival (14.7 months v 9.8 months with new systemic therapy plus RT v 10.2 months with new systemic therapy alone). The greatest benefit was seen in those who had received immunotherapy as part of first line therapy and those with a longer initial progression free interval. This suggests isolated intracranial progression can be effectively controlled by radiation and may not be a reason to throw in the towel when first line therapy is effective everywhere else in the body. Of final note, there were not differences in survival outcomes between those who received whole brain RT vs SRS. | Lu, J Clin Oncol 2026
