In CUP, the PD-L1 positivity rate was 5.6-48.6% (tumor cells [TC] or tumor proportion score [TPS]: 5.6-36.1%, immune cell score [IC]: 8.3-48.6%, combined positive score [CPS]: 16.7%) using different cutoff values for 22C3 (TPS ≥ 1%, CPS ≥ 10), SP142 (TC ≥ 50%, IC ≥ 10%), SP263, and 28 - 8 (TC and IC ≥ 1%). The gene discussed is CD274; the disease is neoplasm.