Previous studies reported poor concordance (kappa value: 0.124–0.340) between PD-L1 (E1L3N) and PD-L1 (SP142) in lung cancer [48], but a high concordance rate between PD-L1 (E1L3N) and PD-L1 (SP142) (more than 85 %) in malignant melanoma [49]. Here, CD274 is linked to lung cancer.