PDCD1 and metastatic melanoma: A group of 137 patients with metastatic melanoma, NSCLC, and RCC treated with WBRT, SRS, or extracranial RT before or after initiation of PD-1 blockade experienced a median OS 249 days (8 months; interquartile range (IQR) 90–689) following the start of anti-PD-1 therapy though OS was 25.7 months in the cohort receiving brain RT as first form of palliative RT [120].