The incidence of melanoma is rising and until recently, metastatic melanoma had a poor survival prognosis. Manipulation of two newly discovered immune pathways have shown impressive results. The first is treatment with anti-cytotoxic T-lymphocyte-antigen (CTLA)-4 antibody which blocks the inhibitory receptor CTLA-4. The other is anti-programmed cell death (PD)-1 antibody which blocks the inhibitory receptor PD-1 on T-cells. Thereby, the T-cells are kept activated and able to attack cancer cells.