National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Renal oncocytoma


Other Names:
Oncocytoma renal; Oncocytoma kidney
Renal oncocytoma is a benign (noncancerous) growth of the kidney. They generally do not cause any signs or symptoms and are often discovered incidentally (by chance) while a person is undergoing diagnostic imaging for other conditions. Some people with renal oncocytoma will have abdominal or flank pain; blood in the urine; and/or an abdominal mass. Although these tumors can occur in people of all ages, they most commonly develop in men who are over age 50. The exact underlying cause of most isolated (single tumor affecting one kidney) renal oncocytomas is unknown; however, multiple and bilateral (affecting both kidneys) renal oncocytomas sometimes occur in people with certain genetic syndromes such as tuberous sclerosis complex and Birt-Hogg-Dube syndrome.[1][2] Although many benign tumors do not require treatment unless they are causing unpleasant symptoms, it can be difficult to confidently differentiate a renal oncocytoma from renal cell carcinoma. Most affected people are, therefore, treated with surgery which allows for confirmation of the diagnosis.[3][4]
Last updated: 3/29/2016
Most people with a renal oncocytoma do not have any signs or symptoms. In fact, these tumors are often discovered incidentally (by chance) while a person is undergoing diagnostic imaging for other conditions. In about a third of cases, people with renal oncocytoma will present with abdominal or flank pain; blood in the urine; and/or an abdominal mass.[1]

Affected people usually have a single, unilateral (only affecting one kidney) renal oncocytoma. However, multiple, bilateral (affecting both kidneys) tumors have rarely been reported in people with tuberous sclerosis complex and Birt-Hogg-Dube syndrome.[2]
Last updated: 2/17/2015

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
Percent of people who have these symptoms is not available through HPO
Abnormality of metabolism/homeostasis
Laboratory abnormality
Metabolism abnormality
[ more ] 		0001939
Mitochondrial inheritance 0001427
Neoplasm 0002664
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Last updated: 7/1/2020
The exact underlying cause of most renal oncocytomas is unknown. However, researchers suspect that acquired (not present at birth) changes in mitochondrial DNA may play a role in the development of some of these tumors.[5]

Renal oncocytomas sometimes occur in people with certain genetic syndromes such as tuberous sclerosis complex and Birt-Hogg-Dube syndrome. In these cases, affected people often have multiple and bilateral (affecting both kidneys) oncocytomas and may also have family members with these tumors. When renal oncocytomas are part of a genetic syndrome, they are caused by changes (mutations) in a specific gene. Tuberous sclerosis complex is caused by mutations in the TSC1 gene or TSC2 gene, while Birt-Hogg-Dube syndrome is caused by mutations in the FLCN gene.[6][7]
Last updated: 2/17/2015
Most renal oncocytomas are not inherited. They usually occur sporadically in people with no family history of tumors. However, in rare cases, they can occur in people with certain genetic syndromes such as tuberous sclerosis complex and Birt-Hogg-Dube syndrome.[2] Both of these conditions are inherited in an autosomal dominant manner.
Last updated: 2/17/2015
A diagnosis of renal oncocytoma is often suspected based on imaging studies such as computed tomography (CT scan) and/or magnetic resonance imaging (MRI scan).[1][2] However, it can be difficult to differentiate a renal oncocytoma from renal cell carcinoma based on imaging studies alone. Although researchers are currently studying several new techniques for the diagnosis of renal oncocytoma, a biopsy is often needed to confirm the diagnosis.[3]
Last updated: 2/17/2015
Most renal oncocytomas are benign (non-cancerous) and metastasis is very rare. Although many benign tumors do not require treatment unless they are causing unpleasant symptoms, it can be difficult to confidently differentiate a renal oncocytoma from renal cell carcinoma based on diagnostic imaging tests alone. Most people are, therefore, treated with surgery which allows for confirmation of the diagnosis. If a renal oncocytoma is strongly suspected prior to surgery, a more conservative procedure such as a partial nephrectomy, may be performed.[4][3]
Last updated: 3/29/2016
The long-term outlook (prognosis) for people with a sporadic (not part of a genetic syndrome) renal oncocytoma is generally good. These tumors are most often benign and metastasis is very rare. After renal oncocytomas are surgically removed, they typically don't recur. The lifespan of affected people is usually not impacted by the tumor.[8][1][2]

When a renal oncocytoma is part of a genetic syndrome such as tuberous sclerosis complex and Birt-Hogg-Dube syndrome, the prognosis varies based on the other associated signs and symptoms.
Last updated: 2/17/2015

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Renal oncocytoma. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Social Networking Websites

Organizations Providing General Support

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Renal oncocytoma. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

  • I was diagnosed with a renal oncocytoma in 2013. Recently I had a lower back MRI and the tumor showed up. Apparently it is now over 5 centimeters in size. How big can these tumors get? Is there ever a time when they need to be removed because of their size? See answer


  1. Sanjeeva P Kalva, MD. Renal Oncocytoma Imaging. Medscape Reference. October 2015; http://emedicine.medscape.com/article/379653-overview.
  2. Michael B Atkins, MD; Toni K Choueiri, MD. Epidemiology, pathology, and pathogenesis of renal cell carcinoma. UpToDate. January 2015; Accessed 2/17/2015.
  3. Schieda N, McInnes MD, Cao L.. Diagnostic accuracy of segmental enhancement inversion for diagnosis of renal oncocytoma at biphasic contrast enhanced CT: systematic review. Eur Radiol. June 2014; 24(6):1421-1429.
  4. Benatiya MA1, Rais G, Tahri M, Barki A, El sayegh H, Iken A, Nouini Y, Lachkar A, Benslimane L, Errihani H, Faik M.. Renal oncocytoma: experience of Clinical Urology A, Urology Department, CHU Ibn Sina, Rabat, Morocco and literature review. Pan Afr Med J. 2012; 12:84.
  5. OMIM. ONCOCYTOMA. September 2011; http://www.omim.org/entry/553000.
  6. Tuberous sclerosis complex. Genetics Home Reference. December 2013; http://ghr.nlm.nih.gov/condition/tuberous-sclerosis-complex.
  7. Birt-Hogg-Dubé syndrome. Genetics Home Reference. January 2013; http://ghr.nlm.nih.gov/condition/birt-hogg-dube-syndrome.
  8. Kuroda N, Toi M, Hiroi M, Shuin T, Enzan H. Review of renal oncocytoma with focus on clinical and pathobiological aspects. Histol Histopathol. July 2003; 18(3):935-42.