In an independent study of melanoma patients, the frequency of TCF1+PD-1+ CD8 TILs did not predict the responsiveness to immune checkpoint blockades, which was different from an earlier study, but a higher percentage of Tpex cells among PD-1+ CD8 TILs was associated with prolonged progression-free survival in responders (9). This evidence concerns the gene PDCD1 and melanoma.