Male breast cancer is a rare cancer that begins as a growth of cells in the breast tissue of men.

Breast cancer is typically thought of as a condition that happens in women. But everyone is born with some breast tissue. So anyone can get breast cancer.

Male breast cancer is rare. It happens most often in older men, though it can occur at any age.

Treatment for male breast cancer typically involves surgery to remove the breast tissue. Other treatments, such as chemotherapy and radiation therapy, may be recommended as well.

Signs and symptoms of male breast cancer can include:

• A painless lump or thickening of the skin on the chest.
• Changes to the skin covering the chest, such as dimpling, puckering, scaling or changes in the color of the skin.
• Changes to the nipple, such as changes in the skin color or scaling, or a nipple that begins to turn inward.
• Discharge or bleeding from the nipple.

When to see a doctor

Make an appointment with a doctor or other health care professional if you have symptoms that worry you.

It's not clear what causes male breast cancer.

Male breast cancer starts when cells in the breast tissue develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time.

In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to make many more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells.

The cancer cells might form a mass called a tumor. The tumor can grow to invade and destroy healthy body tissue. In time, cancer cells can break away and spread to other parts of the body. When cancer spreads, it's called metastatic cancer.

Where breast cancer begins in men

Everyone is born with a small amount of breast tissue. Breast tissue consists of milk-producing glands, ducts that carry milk to the nipples and fat.

During puberty, people assigned female at birth typically begin growing more breast tissue. People assigned male at birth generally do not grow more breast tissue. But because everyone is born with a small amount of breast tissue, breast cancer can develop in anyone.

Types of male breast cancer include:

• Cancer that begins in the milk ducts, called ductal carcinoma. This type of breast cancer starts in the tubes that connect to the nipple. These tubes are called ducts. Ductal carcinoma is the most common type of male breast cancer.
• Cancer that begins in the milk-producing glands, called lobular carcinoma. This type of cancer begins in the glands that have the potential to make breast milk. These glands are called lobules. Lobular carcinoma is less common in people assigned male at birth because they usually have fewer lobular cells.
• Other types of cancer. Other, rarer types of male breast cancer include Paget's disease of the nipple and inflammatory breast cancer.

Factors that increase the risk of male breast cancer include:

• Older age. The risk of breast cancer increases with age. Male breast cancer is most often diagnosed in men in their 60s.
• Hormone therapy for prostate cancer or medicines containing estrogen. If you take estrogen-related medicines, such as those used for hormone therapy for prostate cancer, your risk of breast cancer rises.
• Family history of breast cancer. If you have a blood relative with breast cancer, you have a greater chance of getting the disease.
• Inherited DNA changes that increase breast cancer risk. Some of the DNA changes that can lead to breast cancer are passed down from parents to children. People born with these DNA changes have a greater risk of breast cancer. For example, the DNA changes BRCA1 and BRCA2 increase the risk of male breast cancer.
• Klinefelter syndrome. This genetic syndrome occurs when males are born with more than one copy of the X chromosome. Klinefelter syndrome affects the development of the testicles. It causes changes in the balance of hormones in the body, which can increase the risk of male breast cancer.
• Liver disease. Certain conditions, such as cirrhosis of the liver, can change the balance of hormones in the body. This raises the risk of male breast cancer.
• Obesity. Obesity is linked with higher levels of estrogen in the body. This increases the risk of male breast cancer.
• Testicle disease or surgery. Having inflamed testicles, called orchitis, or surgery to remove a testicle, called orchiectomy, can increase the risk of male breast cancer.

Diagnosing male breast cancer

Tests and procedures to diagnose male breast cancer might include:

• Clinical breast exam. During this exam, a health care professional feels the breasts and surrounding areas for lumps or other changes. This exam helps the health professional understand how large the lumps are, how they feel, and how close they are to skin and muscles.
• Imaging tests. Imaging tests can create pictures of breast tissue to look for signs of cancer. Tests may include a breast X-ray, called a mammogram, an ultrasound or an MRI scan.

• Removing a sample of breast cells for testing, called a biopsy. To determine whether you have cancer, you might have a procedure to remove a sample of cells for testing in a lab. This procedure is called a biopsy. To get the sample, a health care professional puts a needle through the skin on your chest. The health professional guides the needle using a mammogram or another imaging test.

  In the lab, specialists examine the cells under a microscope to see if they're cancer. Other tests can tell whether your cancer cells have hormone receptors or certain DNA changes. The test results help your health care team create a treatment plan.

There might be other tests and procedures depending on your situation.

Staging the cancer

After confirming a diagnosis of breast cancer, your health care team works to find the extent of your cancer. This is called the cancer's stage. Your health care team uses your cancer's stage to understand your prognosis and to make a treatment plan.

Male breast cancer staging often involves imaging tests. The images can tell your health care team about your cancer's size and whether it has spread. Tests may include:

• Bone scan.
• CT scan.
• Positron emission tomography (PET) scan.

Results from lab tests on the cancer cells also help determine the cancer's stage. Tests might show the cancer's grade. This tells your health care team how quickly the cancer is growing. Your care team also considers whether your cancer cells have receptors. Tests can look for receptors for estrogen, progesterone and HER2.

Results from these tests are used to assign your cancer a stage. Breast cancer stages range from 0 to 4. Stage 0 means the cancer is very small. At this stage, the cancer is inside the milk ducts. It hasn't broken out into the breast tissue. Doctors sometimes call this noninvasive cancer.

As the cancer grows and invades the breast tissue, the stages get higher. Stage 4 breast cancer means the cancer has spread to other areas of the body.

Male breast cancer treatment usually starts with surgery. Other common treatments include chemotherapy, hormone therapy and radiation therapy. To create a treatment plan, your health care team looks at your cancer's stage, your overall health and what you prefer.

Surgery

The goal of surgery is to remove the cancer and some of the healthy tissue around it. Operations used to treat male breast cancer include:

• Removing all the breast tissue, called a mastectomy. A mastectomy involves removing all the breast tissue from one side of your chest. This includes removing the nipple and the skin around it, called the areola. This is the most common type of surgery for male breast cancer.
• Removing the cancer and some healthy tissue, called lumpectomy. A lumpectomy involves removing the cancer and some of the healthy tissue around it. The rest of the breast tissue isn't removed. Sometimes doctors call this breast-conserving surgery. Often, radiation therapy is recommended after lumpectomy.

• Removing a few lymph nodes for testing, called a sentinel lymph node biopsy. The surgeon removes the lymph nodes most likely to be the first place your cancer cells would spread. Those few lymph nodes, called sentinel nodes, are sent to a lab for testing.

  If there are no cancer cells, there is a good chance that your breast cancer hasn't spread past your breast tissue. If cancer is found, more lymph nodes are removed for testing.

Radiation therapy

Radiation therapy uses powerful energy beams to kill cancer cells. The energy can come from X-rays, protons or other sources. During radiation therapy, you lie on a table while a machine moves around you. The machine directs radiation to precise points on your body.

In male breast cancer, radiation therapy may be used after surgery to kill any cancer cells that might be left behind. The radiation is often aimed at the chest and armpit.

Hormone therapy

Most male breast cancers have cells that rely on hormones to grow, called hormone sensitive. If your cancer is hormone sensitive, hormone therapy might be an option. Hormone therapy can keep cancer from coming back after surgery. If the cancer spreads to other parts of the body, hormone therapy may help slow its growth.

Hormone therapy for male breast cancer often involves the medicine tamoxifen. Other hormone therapy medicines might be an option if you can't take tamoxifen.

Chemotherapy

Chemotherapy uses strong medicines to kill cancer cells. These medicines are often given through a vein. Some chemotherapy medicines are available in pill form.

Chemotherapy might be used after surgery to kill any cancer cells that might be left in the body. Chemotherapy also may be an option for treating cancer that spreads to other parts of the body.

Targeted therapy

Targeted therapy uses medicines that attack specific chemicals in the cancer cells. By blocking these chemicals, targeted treatments can cause cancer cells to die. Targeted therapy might be used after surgery to kill any cancer cells that might be left in the body. It also might be an option if the cancer spreads to other parts of the body.

Receiving a cancer diagnosis can be shocking. With time, you'll find ways to cope with the stress and challenges of cancer and cancer treatment. Until then, you might find it helpful to consider:

• Talking with someone. You may feel comfortable discussing your feelings with a friend or family member. Or you might prefer meeting with a formal support group. Support groups for the families of cancer survivors also are available.
• Prayer or meditation. You can pray or meditate on your own. Or you can have a spiritual adviser or an instructor guide you.
• Exercise. Gentle exercise may help boost your mood and make you feel better. Ask a member of your health care team about exercises you can do.
• Creative activities. Certain activities, such as art, dance and music, may help you feel less distressed. Some cancer centers have specially trained professionals who can guide you through these activities.
• Relaxation exercises. Relaxation exercises help refocus your mind and help you relax. Relaxation exercises include guided imagery and progressive muscle relaxation. You can do relaxation exercises on your own or with an instructor. You might find it helpful to listen to a recording or watch a video that guides you through the exercises.

Start by seeing your doctor or another health care professional if you notice any symptoms that worry you. You might be referred to a doctor who specializes in treating cancer, called an oncologist.

Here's some information to help you get ready for your appointment.

What you can do

Be aware of any pre-appointment restrictions, such as not eating for a time before your appointment. Ask a relative or friend to go with you to help you remember the information you get.

Make a list of:

• Your symptoms, including any that may seem unrelated to the reason why you scheduled the appointment, and when they began.
• Your key medical information, including other conditions you have or a family history of breast cancer.
• Key personal information, including recent life changes.
• All your medicines, vitamins and supplements, including doses.
• Questions to ask during your appointment.

Basic questions about male breast cancer might include:

• What type of breast cancer do I have?
• What is the stage of my cancer?
• Has my cancer spread beyond the breast?
• Can my cancer be cured?
• Will I need more tests?
• What are my treatment options?
• What side effects might there be for each option?
• Is there a treatment option you feel is best for me?
• How long will cancer treatment last?
• How will cancer treatment affect my daily life?
• I have other health conditions. How can I best manage them together?
• Should I see a specialist?
• Are there brochures or other printed material I can have? What websites do you recommend?

Be sure to ask all the questions you have about male breast cancer.

What to expect from your doctor

Be ready to answer questions such as:

• Are your symptoms ongoing or do they come and go?
• How do your symptoms affect your daily life?
• Have any of your relatives been diagnosed with cancer? If so, what type of cancer and at what age were the family members diagnosed?