The discovery of any kidney mass can be a scary event for anyone. Many questions will need to be addressed to determine the size, nature, and cause of the mass, as well as how it should be treated. Most kidney masses, or tumors as they are commonly called, are benign. This means that they are not cancerous and most of the time not dangerous.

Cancer is probably the most well-known and most feared kidney mass. Kidney or renal cancer is caused when cells begin to divide uncontrollably until they eventually form a mass on one or both kidneys. This type of kidney mass can be life-threatening if not caught and treated early.

Most kinds of kidney mass are not harmful and are non-cancerous. They may form for a variety of reasons and usually present no imminent danger to the patient. What type of kidney mass a patient has is generally determined by doing a biopsy and each tumor is classified by the location and nature of the mass.

Renal adenoma is the most common form of benign kidney mass. Renal adenomas generally present themselves as small growths on either kidney and are mostly asymptomatic. They are usually found during a scan used to check for some other ailment and are. Sometimes they are classified as precancerous and are closely monitored for growth. Often, they are surgically removed to prevent the possibility of cancer in the future.

Another relatively common kidney mass is renal onocytoma. This type of tumor can grow very large and is often found in areas other than the kidneys as well. Men are more likely to get this type of tumor than women, and it is generally found without symptoms. This kind of growth is also considered precancerous and is most often surgically removed.

Angiomyolipoma is a very rare type of kidney mass that usually comes as a side effect of a genetic mutation. This mutation can cause tumors in various parts of the body. The tumors are usually, but not always, accompanied by a condition known as tuberous sclerosis. Patients who do not experience any symptoms related to the tumors are usually watched closely for any changes, but do not receive any treatments unless symptoms appear.

Fibroma is another rare form of kidney mass, and is often not distinguishable from cancerous growths. For this reason, fibromas are generally removed via surgery. Lipomas are also very rare and are considered precancerous and treated appropriately.