Outcomes following LDRT (4 Gy). (A) FFLR at 2 and 4 months was 88.8% and 84.5%, respectively. (B) OS at 1 year following initial LDRT was 90% among the 19 patients. (C) PFS at 1 year following the last course of LDRT was 55%. Nine patients were progression-free at the time of analysis (with a median follow-up of 9.7 months), and 3 patients were completely off systemic therapy since last LDRT course.