CD274 and nasopharyngeal carcinoma: This study investigated the relationship between baseline serum thyroid-stimulating hormone (TSH) and clinical outcomes.<h4>Methods</h4>We conducted a multicenter, retrospective analysis of 153 recurrent/metastatic nasopharyngeal carcinoma (R/M NPC) patients from a prospective phase 2 trial of the PD-L1 inhibitor KL-A167.