Besides the example of anti-cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) antibody (ipilimumab) for the treatment of patients with advanced melanoma [32-34], programmed death 1 (PD-1) might extend the spectrum of immunotherapy clinical activity in tumor types traditionally not considered to be immunogenic, such as metastatic non-small-cell lung cancer [35]. Here, CTLA4 is linked to melanoma.