However, we prefer to attribute this inconsistency in patients with melanoma to the heterogeneity caused by the large proportion of studies investigating CTLA-4 inhibitors (OS: 3 in 7; PFS: 1 in 3), as the additional subgroup analysis revealed that restricting the melanoma cohort to treatment with PD-1 inhibitors yielded significant association between irAE development and a favorable OS. Here, PDCD1 is linked to melanoma.