PDCD1 and melanoma: In the context of predictive personalized immunotherapy, it is noteworthy that the expression of PD-L1 in a range of different types of tumor biopsies (melanoma, NSCLC, renal cell carcinoma, colon carcinoma, bladder carcinoma, and hematologic malignancies) is predictive of a favorable outcome to PD-1/PD-L1-targeted therapy (29).