Our data showed that 22/23 Xp11.2 tRCCs, all 7 PRCC-TFE3 RCCs and 3/40 non- Xp11.2 tRCCs were positive for TFE3 IHC, which indicated the meaninglessness of TFE3 IHC in diagnosing PRCC-TFE3 RCC. This evidence concerns the gene TFE3 and renal cell carcinoma.