HNF1B and cholangiocarcinoma: The expression of Pax8 (Fig. 2c) was positive, but the expression CK7 and HNF1β(Fig. 2d) was positive and that of CD10 and ER was negative, which indicate that the tumor has the feature of clear cell carcinoma of the ovary, not renal cell carcinoma nor cholangiocarcinoma.