KRAS and neoplasm: This initial presentation, along with the histological finding of well-differentiated adenocarcinoma and a molecular profile without mutations in KRAS, NRAS, and BRAF, and programmed death-ligand 1 (PD-L1) expression < 1% (CPS < 1) with a low TMB tumor mutational burden (5 mut/Mb), suggested a poor response to immunotherapy, favoring the use of anti-EGFR over checkpoint inhibitors.