Comparative analysis of programmed cell death ligand 1 assays in renal cell carcinoma.

Programmed death 1 (PD-1)/PD-L1 target therapy may be beneficial for patients with papillary type 2 RCC, even if they are categorised as a heterogeneous group. PD-L1 assays should be carefully selected, and accurate histological subtyping of RCC is needed prior to decisions on PD-L1 testing, because of the different PD-L1 expression observed among varying RCC subtypes.