<h4>Background</h4>Dipeptidyl peptidase 4 (DPP4) plays diverse physiological roles, but its pan-cancer significance and immunomodulatory functions remain poorly characterized.<h4>Methods</h4>We performed an integrative pan-cancer analysis of DPP4, incorporating transcriptomic, genomic, and immunogenomic approaches. The gene discussed is DPP4; the disease is cancer.