CD274 and melanoma: TMB is correlated with clinical response to cytotoxic T lymphocyte–associated antigen−4 blockade in advanced melanoma and with anti–programmed cell death protein−1 (PD-1) and/or PD-L1 blockade in melanoma (Snyder et al., 2014; Van Allen et al., 2015; Hugo et al., 2016; Johnson et al., 2016; Goodman et al., 2017; Cristescu et al., 2018).