We report a rare case of synchronous clear cell renal cell carcinoma and multilocular cystic renal cell neoplasia of low malignant potential in the same kidney. The tumors were seen incidentally in a 45-year-old man. Pathologic study revealed that the former tumor was nucleolar grade 2, and the multilocular cystic renal cell neoplasia of low malignant potential was nucleolar grade 1. At immunohistochemistry, the clear cells in both tumors were positive for CD10 and CA IX. Interestingly, these uncommon synchronous tumors showed a different KRAS/NRAS mutation analysis that was characterized by KRAS mutation at codon p.G12C in the clear cell renal cell carcinoma, while this mutation was not present in the case of multilocular cystic renal cell neoplasia of low malignant potential. NRAS mutation was not seen in any of the tumors.
- Clear cell renal cell carcinoma
- Multilocular cystic clear cell renal cell neoplasm of low malignant potential
ASJC Scopus subject areas
- Pathology and Forensic Medicine
- Cell Biology