What is Renal Mass

Renal mass is a growth in the kidney. A renal mass may be found while performing an MRI, CT scan, or ultrasound for other problems of the abdomen. Certain types of cancers, infections, or injuries can cause a renal mass.

A renal mass that is cancerous (malignant) may grow or spread quickly. Others are harmless (benign).

What are common types of renal masses?

Renal masses include:

• Tumors. These may be cancerous (malignant) or noncancerous (benign).
  • The most common type of kidney cancer is renal cell carcinoma.
  • The most common benign tumors of the kidney include renal adenomas, oncocytomas, and angiomyolipoma (AML).
• Cysts. These are fluid-filled sacs that form on or in the kidney.
  • It is not always known what causes a cyst to develop in or on the kidney.
  • Most kidney cysts do not cause symptoms and do not need to be treated.

What type of testing might I need?

Your health care provider may recommend that you have tests to diagnose the cause of your renal mass. The following tests may be done if a renal mass is found:

• Physical exam.
• Blood tests.
• Urine tests.
• Imaging tests, such as ultrasound, CT scan, or MRI.
• Biopsy. This is a small sample that is removed from the renal mass and tested in a lab.

The exact tests and how often they are done will depend on:

• The size and appearance of the renal mass.
• Risk factors or medical conditions that increase your risk for problems.
• Any symptoms associated with the renal mass, or concerns that you have about it.

Tests and physical exams may be done once, or they may be done regularly for a period of time. Tests and exams that are done regularly will help monitor whether the mass is growing and beginning to cause problems.

What are common treatments for renal masses?

Treatment is not always needed for this condition. Your health care provider may recommend careful monitoring (watchful waiting) and regular tests and exams. Treatment will depend on the cause of the mass.

Follow these instructions at home:

What you need to do at home will depend on the cause of the mass. Follow the instructions that your health care provider gives to you. In general:

• Take over-the-counter and prescription medicines only as told by your health care provider.
• If you are prescribed an antibiotic medicine, take it as told by your health care provider. Do not stop taking the antibiotic even if you start to feel better.
• Follow any restrictions that are given to you by your health care provider.
• Keep all follow-up visits as told by your health care provider. This is important.
  • You may need to see your health care provider once or twice a year to have CT scans and ultrasounds done. These tests will show if your renal mass has changed or grown bigger.

Contact a health care provider if you:

• Have pain in the side or back (flank pain).
• Have a fever.
• Feel full soon after eating.
• Have pain or swelling in the abdomen.
• Lose weight.

Get help right away if:

• Your pain gets worse.
• There is blood in your urine.
• You cannot urinate.
• You have chest pain.
• You have trouble breathing.

Summary

• A renal mass is a growth in the kidney. It may be cancerous (malignant) and grow or spread quickly, or it may be harmless (benign).
• Renal masses may be found while performing an MRI, CT scan, or ultrasound for other problems of the abdomen.
• Your health care provider may recommend that you have tests to diagnose the cause of your renal mass. This may include a physical exam, blood tests, urine tests, imaging, or a biopsy.
• Treatment is not always needed for this condition. Careful monitoring (watchful waiting) may be recommended.