In addition, the present study further investigated whether the number of somatic mutations in the DDR genes of P/LP group was associated with improved survival following programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) or cytotoxic T-lymphocyte-associated protein 4 immunotherapy in CRC patients. The gene discussed is PDCD1; the disease is colorectal carcinoma.