However, five other studies did not find a relationship between PD-L1 status and tumor aggressiveness in cohorts of 64 to 96 carcinomas [14, 40–43], and two further studies even reported a link between high PD-L1 levels and histological parameters of aggressive urothelial cancers in 236 and 248 carcinomas [8, 10]. This evidence concerns the gene CD274 and carcinoma.