PDCD1 and colorectal carcinoma: In patients with CRC receiving CAR-T and anti-PD-1/PD-L1 immunotherapy, SSTR2 could better discriminate between immune responders and non-responders (areas under the receiver operating characteristic curve, 0.933 and 0.782, respectively), and patients receiving CAR-T cells had a better OS, with statistically significant differences.