Treatment of Uveal Melanoma

Uveal melanoma (UM) comprises approximately 5 % of all melanoma diagnoses in the USA each year. Approximately half of patients with UM eventually develop metastases, most commonly involving the liver. Historically, prognosis for these patients has been poor, with death occurring 6-12 months from the time of metastases. Multiple trials of cytotoxic treatments largely extrapolated from cutaneous melanoma have been ineffective in metastatic UM. Trials of regional hepatic-directed therapy have led to high response rates, but these have yet to be translated into a survival benefit. Recently, it was discovered that the majority of UMs harbor activating mutations in genes encoding one of two G-alpha protein subunits, GNAQ and GNA11. This knowledge has led to the rational development of clinical trials specifically for UM utilizing targeted inhibitors of the activated signaling pathways such as mitogen-activated protein kinase, Akt, and protein kinase C. A recent trial of the oral MEK inhibitor selumetinib was the first to show clinical benefit for any systemic therapy in a randomized fashion. This increasing understanding of the biology of UM offers hope that novel treatments will continue to benefit patients with metastatic disease.