Molecular characterization of mucosal melanomas. Molecular characterization of mucosal melanomas

Mucosal melanoma is a deadly disease that carries the worst prognosis amongst subtypes of melanoma. Like all melanomas, mucosal melanomas are frequently driven by activating mutations in the MAPK and/or PI3K pathways; however, unlike melanomas that arise on sun-exposed skin, mucosal melanomas harbor few point mutations. Instead, most somatic alterations involve structural alterations, which appear early during tumor progression. Molecular studies in mucosal melanoma generally only profile point mutations without interrogating copy number alterations, and pathogenic mutations are only found in 30% of cases. We sequenced 38 mucosal melanomas, and in addition to profiling point mutations, we looked for copy number alterations that amplify oncogenes or delete tumor suppressors.