First-line treatment of NRAS-mutated metastatic melanoma with a MEK inhibitor.

Until recently, standard treatment for advanced melanoma comprised basically dacarbazine and interleukin-2, leading to low response rates and significant toxicity. These days, new treatments such as immunotherapy (anti-CTLA4 and anti-PD1 antibodies) and targeted therapy with BRAF/MEK-inhibitor combinations for patients harboring a BRAF mutation are available. In BRAF wild-type patients harboring an NRAS mutation, not fit for immunotherapy treatment options are still dismal. We describe an 84-year-old patient with widespread metastatic melanoma. He presented in July 2015 with a cerebral hemorrhage under anticoagulation for atrial fibrillation. Computed tomography revealed extensive metastatic disease (liver, lung, bones, lymph nodes, heart, and brain). Molecular testing was negative for BRAF but showed the presence of an NRAS mutation in exon 3 (pQ61K [c.181C>A]). The patient received as first-line treatment two cycles of cobimetinib showing a good partial remission and manageable side effects.