Bi Y, et al. - Researchers investigated the expressions of programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1) and their clinicopathologic and prognostic relevance in a relatively large population of medullary thyroid carcinoma (MTC) patients. They analyzed surgical specimens from 87 MTC patients during a median follow-up of 37.7 months. In MTC patients, PD-1/PD-L1 pathway was expressed and showed a significant correlation with the distant metastases at surgery. This suggest PD-1/PD-L1 as a promising therapeutic target in MTC.