Male Breast Cancer

Breast cancer is cancer that forms in the cells of the breast. It is the most common cancer diagnosed in women in the United States, but it can also occur in men. Breast cancer is about 100 times less common among men than among women. For men, the lifetime risk of getting breast cancer is about 1 in 1,000. Male breast cancer accounts for less than 1% of all breast cancers in the United States.

Like for women, the risk of breast cancer in men is influenced by age, family history, inherited gene mutations, hormone levels, and environmental exposure to certain cancer-causing chemicals.

There are many similarities between breast cancer in men and women, but there are some important differences that affect finding it early. The most obvious difference between the male and female breast is size. Because men have very little breast tissue, it is easier for men and health care professionals to feel small masses (tumors). On the other hand, because men have so little breast tissue, cancers do not need to grow very far to reach the nipple, the skin covering the breast, or the muscles underneath the breast. Therefore, even though breast cancers in men tend to be slightly smaller than in women when they are first found, they have often already spread to nearby tissues or lymph nodes. The extent of spread is one of the most important factors in the prognosis (outlook) of a breast cancer.

Another difference is the awareness and amount of attention given to breast cancer in women and men. Women tend to be aware of this disease and its possible warning signs, but many men often do not think that they can get it at all. Some men ignore breast lumps or think they are caused by an infection or some other reason, or some men are embarrassed when they find a breast lump. For these reasons, a man may not get medical treatment until the mass has had a chance to grow. This could delay diagnosis and reduce a man's chances for successful treatment. Because breast cancer is so uncommon in men, there is unlikely to be any benefit in screening men in the general population for breast cancer with mammograms or other tests.

Surgery, radiation therapy, chemotherapy, and hormone therapy are often used to treat breast cancer in men.

Signs and symptoms of male breast cancer may include:

• a lump or swelling in the breast, which is usually (but not always) painless
• skin dimpling or puckering
• nipple retraction (turning inward)
• redness or scaling of the nipple or breast skin
• discharge from the nipple

Sometimes, breast cancer can spread to lymph nodes under the arm or around the collar bone and cause a lump or swelling there, even before the original tumor in the breast tissue is large enough to be felt.

Breast changes are not always caused by cancer. For example, most breast lumps in men are caused by gynecomastia (a harmless enlargement of breast tissue). However, you should see your health care professional as soon as possible if you notice any breast changes.

The cause of breast cancer is not entirely clear. Cancer occurs when some breast cells begin growing abnormally. These cells divide more rapidly than healthy cells do and continue to accumulate, forming a lump or mass. The cells may spread (metastasize) through your breast to your lymph nodes or to other parts of your body.

Hormonal, lifestyle, and environmental factors may increase the risk of getting breast cancer, but it is not clear why some people who have no risk factors develop cancer and other people with risk factors never do. Breast cancer is likely caused by a complex interaction of genetic makeup and environment. A small proportion of breast cancers are linked to gene mutations passed through generations of a family, but there are several inherited mutated genes that can increase the likelihood of breast cancer. The most common are breast cancer gene 1 (BRCA1) and breast cancer gene 2 (BRCA2), both of which significantly increase the risk of both breast and ovarian cancer in women. In men, only BRCA2 seems to be associated with an increased risk of breast cancer.

Other factors that are associated with an increased risk of male breast cancer include:

• increasing age. The risk of breast cancer increases as men age. The average age of diagnosis of male breast cancer is 68 years old.
• a family history of breast cancer. Approximately 1 in 5 men with breast cancer have a close male or female relative with the disease.
• radiation exposure. If you received radiation treatments to your chest as a child or young adult, your risk of breast cancer is increased.
• obesity. Being obese increases the risk of breast cancer.
• drinking alcohol. Drinking alcohol increases the risk of breast cancer.
• estrogen treatment. Men who received estrogen-related therapy for prostate cancer may have a slightly increased risk of breast cancer.
• liver disease. Men with liver disease have altered levels of sex hormones, which may contribute to benign breast conditions and breast cancer.
• testicular conditions. Infections or conditions that affect the testicles may increase the risk for male breast cancer.

Tests and procedures used to screen for and diagnose breast cancer include:

• breast exam. Your doctor will feel both of the breasts and lymph nodes in the armpit, feeling for any lumps or other abnormalities.
• mammogram. A mammogram is an X-ray of the breast. Mammograms are commonly used to screen for breast cancer in women, but they are used strictly for diagnosis in men, meaning a mammogram is only conducted if a problem is suspected.
• breast ultrasound. Ultrasound uses sound waves to produce images of structures deep within the body. Ultrasound may help distinguish between a solid mass and a fluid-filled cyst. An ultrasound is often used to evaluate abnormalities found on a mammogram or physical exam.
• removing a sample of breast cells for testing (biopsy). Biopsy samples are sent to a laboratory for analysis where experts determine whether the cells are cancerous. A biopsy sample is also analyzed to determine the type of cells involved in the breast cancer, the aggressiveness (grade) of the cancer, and whether the cancer cells have hormone receptors or other receptors that may influence your treatment options.
• breast magnetic resonance imaging (MRI). An MRI machine uses a magnet and radio waves to create pictures of the interior of your breast.

If you have or have had breast cancer, you can take steps to manage the stress that accompanies the diagnosis.

Learn about breast cancer so you can make informed decisions about your care.

Have a schedule of follow-up tests and go to each appointment.

Take care of yourself so that you are ready to fight cancer. This includes eating a healthy that includes plenty of fruits, vegetables and whole grains, exercising for at least 30 minutes most days of the week, and getting enough sleep so that you wake feeling rested.

Accept help and support from family and friends.

Talk with other cancer survivors or attend support groups.

Most information about treating male breast cancer comes from doctors' experience with treating breast cancer in women. Because so few men have breast cancer, it is hard for doctors to study the treatment of male breast cancer separately.

The treatments for breast cancer are based on the type of cancer, the stage of the cancer, whether the cancer is sensitive to hormones, your overall health, and your preferences. Most men with breast cancer undergo some type of surgery and they also receive additional treatment before or after surgery, such as chemotherapy, hormone therapy, targeted drug therapy, or radiation.

Surgery. Surgeries used to treat male breast cancer may involve removing the entire breast (mastectomy) or removing lymph nodes involved in the cancer. Surgery may also be performed to remove the testicles, which lowers levels of testosterone.

Radiation therapy. Radiation therapy uses high-powered beams of energy, such as X-rays, to kill cancer cells. Radiation therapy is typically done using a large machine that aims the energy beams at your body (external beam radiation). Radiation can also be done by placing radioactive material inside your body (brachytherapy).

Chemotherapy. Chemotherapy uses drugs to destroy cancer cells. Chemotherapy is sometimes given before surgery in men with larger breast tumors. The goal is to shrink a tumor to a size that makes it easier to remove with surgery. Chemotherapy is also used in men whose cancer has already spread to other parts of the body or has a high risk of recurring. Chemotherapy may be recommended to try to control the cancer and decrease any symptoms the cancer is causing.

Common chemotherapy drugs used in breast cancer include:

• 5-fluorouracil (5-FU)
• Carboplatin
• Cisplatin
• Cyclophosphamide (Cytoxan)
• Docetaxel (Taxotere)
• Doxorubicin (Adriamycin)
• Epirubicin (Ellence)
• Paclitaxel (Taxol)
• Vinorelbine (Navelbine)
• Capecitabine (Xeloda)
• Liposomal doxorubicin (Doxil)
• Gemcitabine (Gemzar)
• Mitoxantrone
• Ixabepilone (Ixempra)
• Albumin-bound paclitaxel (nab-paclitaxel or Abraxane)
• Eribulin (Halaven)

Hormone therapy. Hormone therapy is often used to treat breast cancers that are sensitive to hormones. It can be used after surgery or other treatments to decrease the chance of your cancer returning. If the cancer has already spread, hormone therapy may shrink and control it. Possible hormone therapies include:

• Luteinizing hormone-releasing hormone (LHRH) analogs such as leuprolide (Lupron) and goserelin (Zoladex) affect the pituitary gland and decrease production of the male hormone testosterone by the testicles, leading to lower testosterone levels. These drugs may be used by themselves, or combined with aromatase inhibitors or anti-androgens to treat advanced breast cancer in men. Anti-androgens such as flutamide and bicalutamide work by blocking the effect of male hormones on breast cancer cells.
• Megestrol (Megace) is a progesterone-like drug. It is unclear how it stops cancer cells from growing, but it appears to compete for hormone receptor sites in the cells. This is an older drug that is usually reserved for men who are no longer responding to other forms of hormone therapy.

Targeted therapy. Targeted drug treatments attack specific abnormalities such as protein growth within cancer cells. Targeted drugs used to treat breast cancer include: ado-trastuzumab (Kadcyla), Bevacizumab (Avastin), lapatinib (Tykerb), pertuzumab (Perjeta), and trastuzumab (Herceptin).