What are oncocytomas?

  • Oncocytomas are a type of tumour, usually benign. While these tumours can occur in different areas of the body, oncocytomas commonly refer to renal (kidney) oncocytomas.
  • Renal oncocytomas can grow inside the kidney or on the surface. While benign, oncocytomas can damage the kidneys as they may grow in places that might affect kidney blood flow.
  • Oncocytomas do not seem to metastasise, or spread.  
  • Oncocytomas can be implicated in a number of diseases, including Birt-Hogg-Dubé syndrome. For more information on BHD, visit BHDSyndrome.org
  • About 3% of BHD-related kidney tumours are exclusively oncocytomas. 67% of BHD kidney tumours are hybrid (oncocytomas mixed with another type of tumour).