CTLA4 and metastatic melanoma: The treatment of metastatic melanoma has been revolutionized in the last three years, with the FDA registration of YervoyTM, a monoclonal antibody blocking lymphocyte regulatory receptor cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), and shortly afterward, the entry to the clinic of Zelboraf, a small molecule inhibitor of mutated B-RAF.