PDCD1 and melanoma: Additionally, a separate report found that 67% of melanoma patients who developed resistance following the initial response to anti-PD-1 monotherapy or a combination of anti-PD-1 and anti-CTLA-4 therapy exhibited increased numbers of intratumoral V-domain Ig suppressor of T cell activation (VISTA)+ lymphocytes upon disease progression compared with pretreatment levels (86).