PAX8 and papillary renal cell carcinoma: Papillary renal cell carcinoma, type 1 is a PAX8+ , vimentin+ , CK7+ , AMACR+ , WT1−, CD57−, BRAF− tumor as opposed to metanephric adenoma that is positive for WT1, CD57, and BRAF but negative for CyK7.