Renal Oncocytoma: Causes, Symptoms, and Treatment
Written by Achuta Uppu, MD. Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Renal Oncocytoma?
The tumor is usually removed by a urologist, a surgeon who treats the urinary system. A nephrologist, a doctor who specializes in kidney health, often helps as well, and a radiologist reads the imaging tests. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is a renal oncocytoma?
A renal oncocytoma is a noncancerous growth that forms inside the kidney. It is benign, which means it does not spread to other parts of the body. It is often found by accident during imaging tests.
A renal oncocytoma is a tumor, an abnormal lump of cells, that grows slowly inside the kidney. Doctors cannot always tell it apart from kidney cancer on a scan, so it is often treated like cancer until testing proves otherwise.
Symptoms
Most renal oncocytomas cause no symptoms at all and are often found on a CT scan or ultrasound done for another problem. When symptoms do happen, they can include dull pain in the side or back, blood in the urine, or a lump in the belly.
Causes and who gets it
Doctors do not know exactly what causes renal oncocytomas. They are more common in men and are usually found in adults between about 50 and 70 years old.
How doctors diagnose it
Most renal oncocytomas are found by chance on a scan. Doctors use imaging tests, such as CT or MRI, to learn more. Because oncocytomas can look very similar to kidney cancer, the only way to know for sure is to examine cells under a microscope.
Treatment
Treatment depends on the size of the tumor, the symptoms it causes, and the person's overall health. Because scans cannot always rule out cancer, many people have surgery. Surgeons try to remove only the tumor and keep as much healthy kidney as possible. Some small tumors that look benign can be watched with regular imaging instead.
When to see a doctor
Anyone who notices blood in the urine should see a doctor. Ongoing side or back pain, or a lump in the belly, are also reasons to go. People with a kidney tumor should keep all follow-up appointments.
How a direct primary care or concierge doctor fits in
A direct primary care doctor is paid a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either one can order imaging tests, review results, and refer the patient to a specialist when needed.
Common questions
Is a renal oncocytoma cancer?
No, it is a benign tumor, which means it does not spread to other organs. The challenge is that it can look like kidney cancer on scans. Doctors often treat it as if it could be cancer until lab testing proves otherwise.
Can it turn into cancer?
Doctors generally consider renal oncocytomas to be noncancerous growths that do not become cancer. Because scans cannot always tell them apart from kidney cancer, careful follow-up or removal is usually recommended.
Will I lose my whole kidney?
Not always. Surgeons today often remove just the tumor and leave the rest of the kidney in place, especially when the tumor is small. The exact surgery depends on the size and location of the tumor.
How common are these tumors?
Renal oncocytomas make up a meaningful share of kidney tumors found on imaging. Some studies suggest they account for a small percentage of all kidney growths. Many are found by accident in people who have no symptoms.
Sources
- MedlinePlus - Kidney Cancer
- National Institute of Diabetes and Digestive and Kidney Diseases - Kidney Disease - NIDDK
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
