CTLA4 and metastatic melanoma: This study included forty patients with metastatic melanoma (stage IV or unresectable stage III American Joint Committee on Cancer [AJCC], 8th edition [24]) treated with anti-PD-1 alone (nivolumab or pembrolizumab; 65%, 26/40) or in combination with anti-CTLA-4 (anti-PD-1 + ipilimumab; 35%, 14/40), who had progressive disease or stable disease for less than or equal to 6 months (Table 1 and Supplementary Table S2).