(See also Overview of Skin Cancer.)
The term Paget disease also refers to an unrelated metabolic bone disease (see Paget Disease of Bone). These distinct diseases should not be confused with each other.
This Paget disease occurs mainly on the nipple and results from a cancer of the breast milk ducts that has spread to the skin of the nipple. Both men and women are affected. The underlying cancer may or may not be felt by the person or the doctor.
Sometimes Paget disease of the nipple develops in areas other than the breast (called extramammary Paget disease). It can develop in the groin or genital area or around the anus as the result of a cancer originating in underlying sweat glands or even in nearby structures such as the bladder, anus, and rectum.
The skin in Paget disease of the nipple appears red, oozing, and crusting, similar to dermatitis but with a sharp border. Itching and pain are common.
Because Paget disease looks very much like common dermatitis, a biopsy is necessary to make the diagnosis. During this procedure, a small piece of skin is removed and examined under a microscope.
As with other cancers, once the diagnosis of Paget disease of the nipple is confirmed, doctors do an examination and tests to see whether the cancer has spread.
Paget disease of the nipple is usually treated like other types of breast cancer, and the nipple and areola are surgically removed.
Paget disease outside the breast area is treated by removing the entire growth with surgery, drugs applied to the skin, radiation therapy, or laser therapy.