CD274 and melanoma: Although for tumors of some localizations such as NSCLC, or TNBC, PD-L1 testing is really critical for using immuno-oncological drugs in first line treatment as mono-therapy or in combinations with the best efficacy and toxicity profile, for others such as melanoma, immunotherapy is effective in itself, is minimally associated with the level of PD-L1 expression and, apparently, does not require its dynamic assessment over time.