However, PD-1/PD-L1 inhibitors show substantial antitumor effects in only a small subset of patients, with most individuals exhibiting a low response rate to these treatments [10], especially those with microsatellite stable (MSS)/mismatch repair-proficient (pMMR) colorectal cancer (CRC) subtypes [11]. The gene discussed is PDCD1; the disease is colorectal cancer.