Immunohistochemical staining showed that the tumor cells were positive for CK-p, Vimentin, PAX8, CAIX, P504S, Claudin7, FH, a small amount of positive RCC, Ki-67 (20%+), P53 (10%+), and TFE-3 (weakly positive). This evidence concerns the gene PAX8 and renal cell carcinoma.