The positive immunohistochemical expression was as follows: RCC (6/8), PAX-8 (3/3), and PAX-2 (4/4), CK7 (10/10), Vimentin (4/4), and EMA (6/6), and AMACR (6/6), CA9 (0/4), CD117 (0/5), CD10 (2/9). Here, CA9 is linked to renal cell carcinoma.