CD274 and neoplasm: Although Zheng et al. [12] found a statistically positive correlation between PD-L1 positivity and tumor size, no statistically significant difference was found as comparing with tumor size and PD-L1 immunopositivity in our study, which might be due to positive expression of PD-L1 in 75% of all patients as compared with 52.5% expression according to the study by Zheng et al.