Malignant Melanoma with Concurrent BRAF E586K and NRAS Q81K Mutations

Abstract

Cutaneous melanoma is an aggressive malignant tumor of melanocytes which accounts for 80% of skin cancer-related deaths. A number of driver mutations have been identified in melanoma, with the mutually exclusive BRAF V600E and NRAS Q61A mutations together accounting for roughly 70% of mutations. Simultaneous BRAF V600E and NRAS Q61A mutations in melanoma are rare, with evidence suggesting that up to 2.9% (2/69) of primary cutaneous melanomas carry both mutations. Here we describe a 42-year-old man with concurrent BRAF E586K and NRAS Q81K driver mutations. To our knowledge, this is the first description of these driver mutations occurring simultaneously in primary cutaneous melanoma.

Keywords: Concurrent BRAF E586K and NRAS Q81K mutations; Cutaneous melanoma; Skin cancer.

Fig. 1

Representative HE and IHC staining results of the cutaneous melanoma removed from the patient's back. a High-power staining of the melanoma showing epithelioid pleomorphic malignant cells. b IHC staining showing S100 positivity typical of melanomas. c IHC staining showing dual Mart-1 (membranous) and Ki-67 (nuclear) positivity, also consistent with melanomas.