The following is a summary of “Distinct genomic features in a retrospective cohort of mucosal, acral, and vulvovaginal melanomas,” published in the MAY 2023 issue of Dermatology by Shi, et al.

Sun-protected melanomas have a different pathogenesis than sun-exposed melanomas. While sun-protected melanomas share several epidemiologic factors, their genetic heterogeneity is not well understood. For a study, researchers sought to investigate the genomic profile of melanomas in sun-protected areas (acral, mucosal, and vulvovaginal) and to determine whether mucosal melanomas have distinct genomic features.

Whole transcriptome messenger RNA and DNA sequencing (1,711 genes), messenger RNA expression profiling, tumor mutational burden, ultraviolet signature, and copy number variant analysis were performed on 29 volar/digital acral, 7 mucosal, and 6 vulvovaginal melanomas.

Significant genetic heterogeneity was observed, especially in acral melanomas, where 36% had BRAF alterations, compared to none in other melanomas (P = .0159). Nonzero ultraviolet signatures were more frequent in acral melanomas, indicating greater ultraviolet involvement. Mucosal melanomas formed a distinct group with increased expression of cell cycle and proliferation genes. Various targetable aberrations were identified, such as AURKA and ERBB2, in mucosal and acral melanomas, respectively.

Sun-protected melanomas have significant genetic heterogeneity, with mucosal melanomas having upregulation in cell cycle and proliferation genes, potentially explaining their aggressive behavior. Ultraviolet radiation may play a role in a subset of acral melanomas, but not other melanomas. The study provided valuable insights into the genetic profiles of sun-protected melanomas.

Source: jaad.org/article/S0190-9622(19)32374-6/fulltext