Clear Cell Renal Cell Carcinoma
Definition
- Carcinoma of the kidney composed predominantly of nests and sheets of clear cells
Alternate/Historical Names
- Conventional type renal cell carcinoma
- One of several different neoplasms previously diagnosed as granular cell renal cell carcinoma (some cases)
Diagnostic Criteria
- Grossly circumscribed mass
- Frequently hemorrhagic and necrotic
- Soft yellow areas frequent, alternating with fibrous to mucoid areas
- May appear necrotic but frequently are viable
- Multifocal in about 5% of cases
- More frequent in familial cases
- Sheets and nests of cells surrounded by extensive capillary network
- Frequently forms alveolar lumens
- No lumenal border differentiation
- Frequently dilates to form micro- and macrocystic pattern
- If exclusively cystic, see multilocular cystic renal cell carcinoma
- Lumens may contain eosinophilic proteinaceous fluid or RBCs
- Tubular and papillary foci rare
- Consider clear cell tubulopapillary carcinoma if present
- Frequently forms alveolar lumens
- Predominantly composed of clear cells
- Higher grade tumors often lose clear cell cytoplasm but may still have underlying recognizable low grade clear cell areas
- Frequent granular eosinophilic areas
- Rarely predominant
- If extensively granular and eosinophilic, consider oncocytoma
- Sharp cell borders
- Cytoplasm contains lipid and glycogen
- Features reported in rare cases
- Rhabdoid cells in 5% of cases
(Gokden 2000)
- Abundant eccentric cytoplasm containing large eosinophilic inclusions
- Eccentric large round nuclei, may be multinucleate
- Keratin, EMA, vimentin positive
- 25% of cases with rhabdoid areas have sarcomatoid areas
- Eosinophilic 5-7 mm hyaline globules (Jagirdar 1985)
- Basophilic inclusions
- Myospherulosis (Chau 2000)
- Coarse brown granular pigment (one case, Kamishima 1995, Fukuda 1997)
- Melanin (one case, Lei 2001)
- Rhabdoid cells in 5% of cases
(Gokden 2000)
- Nuclei range from round and regular at low grade to pleomorphic at high grade
- Nuclear features and nucleolar size incorporated into grading
- Dysplasia of adjacent non-carcinomatous tubules has been reported
- Multiple and/or familial clear cell carcinomas may be seen in von Hippel Lindau syndrome
John P Higgins MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting/updates: 1/24/11, 8/8/11
