LAUSR

Key Points Question When compared with prior therapies, are immune checkpoint inhibitors for metastatic melanoma associated with development of second primary cancers? Findings In this cohort study of 5016 patients with metastatic melanoma between 2005 and 2016, the overall risk of second primary cancers increased after the introduction of immune checkpoint inhibitors. Risks for cancer of the small intestine and myeloma were higher than before the era of immune checkpoint inhibitors. Meaning In this study, a change in the incidence of second primary cancers was found; screening for these cancers may be warranted in patients treated with immune checkpoint inhibitors for metastatic melanoma.