PDCD1 and cancer: In the HNSCC cohort, the presence of <71% Ecad+ cancer cells, >21% Vim+, CD80+ and CD155+ cancer cells, and >7% Ecad−Vim+, Ecad−CD80+ and Ecad−CD155+ cancer cells might be risk factors for anti-PD-1/PD-L1 resistance (Supplementary Figs. 8f–j and 9e–h).