Immunotherapy for mucosal melanoma

Abstract Mucosal melanoma (MM) is extremely rare in Caucasians, whereas it is the second predominant melanoma subtype in Asian and other non-Caucasian populations. Distinct from cutaneous melanoma in terms of epidemiology, biology, and molecular characteristics, MM is characterized by more aggressive biological behavior, lower mutational burden, more chromosomal structure variants, and poorer prognosis. Because of the rarity of MM, its biological features are not fully understood, and potential novel therapies are less well depicted. Whereas immunotherapy has shown encouraging efficacy for cutaneous melanoma, its efficacy in MM is unclear due to limited sample sizes in clinical trials. Thus, in this review, we describe the epidemiological, clinical, and molecular features of MM and summarize the efficacies of different immunotherapies for MM, including immune checkpoint inhibitors, vaccines, oncolytic virus therapy, adoptive T-cell therapy, and various combination therapies.