BRAF, KIT, and NRAS Mutations of Acral Melanoma in White Patients.

Abstract

Malignant acral melanoma (AM) is relatively infrequent in white patients. Molecular investigations have returned variable results regarding the mutational pattern. We sought to describe the mutation profile and clinicopathologic features of AM. We investigated BRAF, KIT, and NRAS mutational status in a series of 31 AM samples from white patients. Nodular melanoma was the most common histopathologic subtype (48.4%), followed by acral lentiginous melanoma (25.8%) and superficial spreading melanoma (25.8%). BRAF, KIT, and NRAS mutational rates were 12.9%, 17.2%, and 30.0%, respectively. We observed significant associations between KIT mutational status and a thinner Breslow thickness compared with wild-type (WT) status (P = .002), NRAS mutation status and younger age compared with WT. In patients presenting at least one mutation, triple-WT patients presented metastases most frequently. Although these data represent preliminary results, better knowledge of tumor biology and prognosis of AM can support the clinical approach and follow-up.