Cite this page: Unclassified renal cell carcinoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/kidneytumormalignantnos.html. Accessed February 21st, 2018.
Definition / general
- Tumors that cannot be otherwise classified, often because they have features fitting more than one category
- 5% of all renal tumors
- Tumors are histologically heterogeneous and often high grade (93% Fuhrman's nuclear grade 3 or 4) and high stage (45% - 83% stage 3 and 4, Am J Surg Pathol 2002;26:281, BJU Int 2007;100:802)
- However, tumors that closely resemble oncocytoma but show unusual features may also fall into this category
- Molecular techniques may be useful
- Tumor with features of oncocytoma, chromophobe carcinoma, collecting duct carcinoma and sarcomatoid carcinoma (Arch Pathol Lab Med 2004;128:1274)