PIK3CA and nonpapillary renal cell carcinoma: To investigate whether SALL4 overexpression is enriched in tumors with driver gene mutations, we analyzed the association between SALL4 expression and the mutation profile of most commonly altered genes (VHL, PBRM1, SETD2, KDM5C, BAP1, PTEN, MTOR, TP53 and PIK3CA) in ccRCC.