CDKN2A and metastatic melanoma: In a retrospective study of 19 metastatic melanoma patients with germline CDKN2A mutations, with 11 of the 19 carriers (58%) responding to immunotherapy, it was found that response to immunotherapy was significantly higher than that observed in clinical trials (p = 0.03, binomial test against an expected rate of 37%); a higher rate of complete responses was also observed, with six of the 19 carriers (32%) achieving a complete response (p = 0.01, binomial test against an expected rate of 7%) [5].