Many benign kidney tumors don’t cause symptoms. But when symptoms do occur, they can include blood in the urine and pain in the lower back or between the ribs and hips.

Benign kidney tumors are noncancerous growths of atypical cells that don’t spread to other parts of the body. Lifestyle and genetic factors may increase your chance of developing a benign kidney tumor.

Most growths that develop in the kidneys aren’t cancerous, and up to 20% of small kidney tumors are benign. Doctors typically detect them with scans and treat them with surgery.

Even if a kidney tumor is benign, it can cause health difficulties. You may experience pain or blood in your urine.

Many small tumors won’t cause signs or symptoms, and a doctor may only discover them when they’re treating another condition.

If you do experience symptoms, they can include the following.

Blood in your urine (hematuria)

It’s important to get medical help right away if you notice blood in your urine or you’re having pain when urinating. Blood in the urine can be related to an infection.

However, blood may only be visible under a microscope.


A kidney tumor may cause pain in the lower back. You may also experience pain between your ribs and hips.

Loss of appetite and unexplained weight loss

You may find that you have no interest in eating or that you feel full very quickly.


Healthy kidneys help the body make more red blood cells by producing the hormone erythropoietin (EPO). If a tumor affects the amount of EPO released or causes you to lose red blood cells in your urine, you may develop anemia.


This fever may come and go or be continuous. It may be linked to an infection.

Some types of benign kidney tumors include:

  • renal adenoma
  • renal oncocytoma
  • angiomyolipoma
  • fibroma
  • lipoma
  • reninoma
  • renal schwannoma
  • renal hemangioma

Papillary renal adenomas are the most common type of noncancerous kidney tumors.

The cause of many benign kidney tumors is unknown. However, some factors that may increase your chance of developing a benign or cancerous kidney tumor include:

  • smoking
  • consuming excessive amounts of alcohol
  • having a family history of conditions like polycystic kidney disease
  • having overweight or obesity
  • having exposure to certain chemicals and medications

Older research from 2015 suggests that kidney tumors may grow at an average rate of around 0.3 centimeters per year.

However, benign kidney tumors can grow at a variety of rates. The speed at which a tumor grows can depend on the type of tumor you have, your age, and your overall health.

Doctors can spot tumors in the kidneys via ultrasounds, as well as CT scans and MRI scans. They frequently detect them during procedures for other medical issues.

To find out if a kidney tumor is benign or malignant, your doctor will need to perform a biopsy, which involves taking a small sample of the tumor.

The primary form of treatment for benign kidney tumors is surgery to remove the tumor. However, your doctor may recommend other treatment options, including a wait-and-see approach, depending on the size and location of the tumor.

If a kidney infection or abscess is responsible for the tumor, you may need to take antibiotics as part of the treatment.

It’s best to contact a doctor if you have any symptoms of a kidney tumor, such as blood in your urine.

It’s important to get medical help anytime you have any concerns.

Here are answers to some of the most common questions about benign kidney tumors.

How serious is a benign kidney tumor?

Although benign tumors aren’t cancerous, depending on the size and location of the tumor, they can cause pain, blood in your urine, and other symptoms. Some benign kidney tumors may be more serious than others depending on their underlying cause.

Should a benign kidney tumor be removed?

Your doctor will consider many factors, like the size and location of the tumor, when determining if it requires removal.

What can be mistaken for a kidney tumor?

Cysts and kidney stones are some things people may mistake for a kidney tumor.

Although benign kidney tumors are noncancerous, they may cause blood in your urine and pain in your lower back or between your ribs and hips.

It’s possible to experience no symptoms with a benign kidney tumor. A doctor may only find a tumor during an imaging scan for another condition or symptom. If you have a benign kidney tumor, your doctor may recommend surgery to remove it.