General Information: Cysts

What is a Cyst?

A cyst is a closed sac-like structure that is not a normal part of the tissue where it is found. Cysts are common and can occur anywhere in the body in people of any age. Cysts usually contain a gaseous, liquid, or semisolid substance. Cysts vary in size; they may be detectable only under a microscope or they can grow so large that they displace normal organs and tissues. The outer wall of a cyst is called the capsule.

What are the causes of a cyst?

Signs & Symptoms:

Sometimes you can feel a cyst yourself when you feel an abnormal "lump." For example, cysts of the skin or tissues beneath the skin are usually noticeable. Cysts in the mammary glands (breasts) also may be palpable (meaning that you can feel them when you examine the area with your fingers). Cysts of internal organs such as the kidneys or liver may not produce any symptoms or may not be detected by the affected individual. These cysts often are first discovered by imaging studies (x-ray, ultrasound, computerized tomography or CAT Scan, and magnetic resonance imaging or MRI). Cysts may or may not produce symptoms, depending upon their size and location.

The majority of cysts are benign, but some may produce symptoms due to their size and/or location. Rarely, cysts can be associated with malignant tumors (cancers) or serious infections. If you're concerned about any abnormal swelling or lump, talk to your doctor. He or she can recommend appropriate diagnostic tests to determine the cause of the cyst.

Treatment:

The treatment for a cyst depends upon the cause of the cyst along with its location. Cysts that are very large and result in symptoms due to their size may be surgically removed. We try to remove the cyst with the entire sac intact. Sometimes if the sac is incompletely removed the cyst will reform. Sometimes the fluid contained within a cyst can be drained, or aspirated, by inserting a needle or catheter into the cyst cavity, resulting in collapse of the cyst. Radiologic imaging may be used for guidance in draining (aspirating) cyst contents if the cyst is not easily accessible.

If there is any suspicion that a cyst is cancerous, the cyst is generally removed by surgery or a biopsy is taken of the cyst wall (capsule) to rule out malignancy. In certain cases, aspirated fluid from a cyst is examined under a microscope to determine if cancer cells are present in the cyst.