Male breast cancer is rare and accounts for only about 1% of all breast cancers. Breast cancer risk in men is increased by elevated levels of estrogen, previous radiation exposure, and a family history of breast cancer. A lump beneath the nipple is the most common symptom of male breast cancer. Men possess a small amount of non-functioning breast tissue (breast tissue that cannot produce milk) that is concentrated in the area directly behind the nipple on the chest wall. Like breast cancer in women, cancer of the male breast is the uncontrolled growth with the potential for spread of some of the cells of this breast tissue. These cells become so abnormal in appearance and behavior that they are then called cancer cells.
What are causes and risk factors of male breast cancer?
The following risk factors for the development of male breast cancer have been identified.
1. Exposure to ionising radiation has been associated with an increased risk of developing male breast cancer.
2. Men normally produce small amounts of the female hormone estrogen, but certain conditions result in abnormally high levels of estrogen in men. The term gynecomastia refers to the condition in which the male breasts become abnormally enlarged in response to elevated levels of estrogen.
3. Klinefelter’s syndrome is an inherited condition affecting about one in 1,000 men. A normal man has two sex chromosomes (X and Y). Men with Klinefelter’s syndrome have an extra female X chromosome, resulting in an abnormal sex chromosome makeup of XXY and produce high levels of estrogen and develop enlarged breasts, sparse facial and body hair, small testes, and the inability to produce sperm.
4. Cirrhosis can result from chronic alcohol abuse, chronic viral hepatitis, or rare genetic conditions that result in accumulation of toxic substances within the liver.
What are male breast cancer symptoms and signs?
The most common sign of breast cancer in men is a firm, nonpainful mass located just below the nipple. There may not be other associated symptoms. The average size of breast cancer in men when first discovered is about 2.5 cm in diameter. The cancer may cause skin changes in the area of the nipple. These changes can include ulceration of the skin, puckering or dimpling, redness or scaling of the nipple, or retraction (turning inward) of the nipple. Bloody or opaque discharge from the nipple may also occur. Less than 1% of cases are bilateral (occurring on both sides).
Breast cancer that has spread (metastasized) to the bones may also produce bone pain at the sites of metastases. Advanced breast cancer can also produce symptoms typical of many cancers, including malaise, weakness, and weight loss. Breast cancer in men can spread to many other organs and cause other symptoms as well.
How is male breast cancer diagnosed?
Diagnosis of breast cancer requires identifying cancer cells in tissue specimens obtained by taking a sample of the growth – also called a “mass” or “tumor” – by the technique of biopsy.
What is the treatment for male breast cancer?
1. Most men diagnosed with breast cancer are initially treated by surgery. A modified radical mastectomy (removal of the breast, lining over the chest muscles, and portions of the underarm or axillary lymph nodes) is the most common surgical treatment of male breast cancer. Sometimes portions of the muscles of the chest wall are also removed.
2. Chemotherapy refers to the administration of toxic drugs that stop the growth of cancer cells, or even kill some of them.
3. Radiation therapy uses high-energy radiation to kill tumor cells. Radiation therapy may be delivered either externally (using a machine to send radiation toward the tumor) or internally (radioactive substances placed in needles or catheters and inserted into the body).
4. Hormonal therapy prevents hormones from stimulating growth of cancer cells and is useful when the cancer cells have binding sites (receptors) for hormones.