CD8A and metastatic melanoma: To determine if a bulk immune cell presence could be correlated to responsiveness, we performed CD8+ and CD3+ immunohistochemical staining and cell counting to quantify T-cells at the invasive margin and intratumoral region in metastatic melanoma tissue samples, matched for size, prior to any exposure to ICI therapies (Fig. 1a,c) (N = 4 per group).