Male Breast Cancer

What is male breast cancer?

Male breast cancer is a type of cancer that grows in the breast tissue in your chest. Although men and people assigned male at birth (AMAB) don’t have breasts that produce milk, they have fatty tissue, ducts and breast cells that can become cancerous. Cancer develops when cells in these tissues grow uncontrollably, forming a tumor.

Male breast cancer is extremely rare compared to breast cancer in women and people assigned female at birth (AFAB). Still, many steps involved in diagnosing and treating breast cancer are similar regardless of sex.

Types of male breast cancer

Cancer is most likely to form in your breast ducts. Ducts are tubes that connect glands called lobules to your nipple. Types include:

• Invasive (infiltrating) ductal carcinoma: Up to 90% of male breast cancers are invasive ductal carcinoma, the most common type of breast cancer. Cancer begins in your breast ducts and spreads to other parts of your breast. Cancer cells may also spread to other areas of your body.
• Ductal carcinoma in situ (DCIS): Cancer cells grow in the lining of your breast ducts. “In situ” means that the cells haven’t spread to other parts of your breast or the rest of your body.
• Lobular breast cancer (invasive lobular carcinoma): Cancer cells form in the lobules. Like invasive ductal carcinoma, lobular breast cancer can spread to other parts of your body.

Rarer types of male breast cancer include inflammatory breast cancer and Paget’s disease of the breast.

How common is male breast cancer?

It’s uncommon. Only about 2,800 people AMAB in the United States receive this diagnosis annually. This is less than 1% of total breast cancer cases among either sex.

What are the signs and symptoms of breast cancer in men?

Physical changes in your breast tissue are often the first noticeable signs of breast cancer.

Male breast cancer symptoms include:

• A firm, painless lump in your breast tissue, behind your nipple or in your armpit.
• Skin on your chest that looks dimpled or pitted, like the skin of an orange.
• Red, flaky or scaly skin on your chest or near your nipple.
• Pain or tenderness in your chest or underarm.
• Clear or bloody nipple discharge or an inverted nipple (a nipple that’s sunken inward instead of sticking out).

What causes male breast cancer?

Uncontrolled cell growth in your breast tissue causes male breast cancer. Tumors form when healthy cells transform into cancer cells. Unlike healthy cells, cancer cells multiply rapidly and don’t die. Eventually, cells from the tumor may break off and travel to other parts of your body via your lymphatic system or bloodstream. Cancer that’s spread is called metastatic. Treatment for breast cancer that’s spread will differ in some ways from cancer that’s contained in your breast and lymph nodes.

Scientists continue to research what causes healthy cells to become cancer cells.

In the meantime, they’ve identified several factors that may increase your risk of developing breast cancer.

Risk factors

Age and race are related to male breast cancer risk. Most people diagnosed are over age 60. Male breast cancer diagnoses are more common in people who are Black.

Other risk factors include:

• Family history: You’re at greater risk if you have a parent, sibling or child (of either sex) with breast cancer.
• Genes: Mutations (changes) in your genes increase your risk of developing breast cancer. These include changes in the BRCA gene (BRCA1 and BRCA2). Less common gene mutations associated with breast cancer also occur in conditions such as Cowden syndrome (PTEN gene), Li-Fraumeni syndrome (TP53) and Lynch syndrome (MMR gene).
• Conditions that raise estrogen levels: High estrogen levels can increase your risk. Conditions that raise your estrogen include obesity, cirrhosis of the liver and a genetic disorder called Klinefelter syndrome.
• Estrogen-containing medications: Taking estrogen-containing drugs can increase your cancer risk. These include hormone replacement, including drugs taken as part of feminizing hormone therapy. A recent study suggests that among people assigned male at birth, transgender women who receive hormone therapy are more likely to develop breast cancer than cisgender men.
• Testicular issues: Your risk increases if you’ve had surgery to remove a testicle (orchiectomy), an injury or a condition involving your testicles. These include having inflamed testicles (orchitis) or undescended testicles.
• Radiation therapy: You’re more likely to develop breast cancer if you’ve had prior radiation therapy directed at your chest or torso.

How is male breast cancer diagnosed?

Your healthcare provider will ask about your symptoms, family history of breast cancer and other risk factors. They’ll perform various tests or procedures to make a diagnosis, including:

• Breast exam: Your healthcare provider will examine your breast tissue, checking for skin changes, lumps or other abnormalities.
• Imaging tests: Mammograms can detect the majority of male breast cancers. A mammogram is a low-dose X-ray that takes pictures of your breast tissue. Your provider may also perform an ultrasound. An ultrasound uses sound waves to take pictures of your breast tissue.
• Biopsy: Your healthcare provider will perform a biopsy to look for cancer cells in your breast tissue. For this procedure, your provider removes tissue from the tumor and sends it to a lab for testing.

Testing the cancer cells in a lab allows healthcare providers to diagnose cancer and plan treatments that work best on certain types of cancer cells.

With breast cancer, providers look for proteins on cancer cells called receptors. These proteins include estrogen receptor (ER), progesterone receptor (PR) and HER2/neu receptor. These cell features provide important information about what’s causing cancer cells to grow.

What are the stages of male breast cancer?

After diagnosing breast cancer, providers classify it using a process called staging. Staging uses information like tumor size and cancer spread to determine how advanced the disease is.

You may need imaging tests such as a PET scan, bone scan or CT scan that can show where cancer cells are inside your body. Your provider may perform a sentinel node biopsy as part of staging. For this procedure, your provider removes one or more lymph nodes near a tumor and tests them for cancer cells.

The stages of male breast cancer are:

Stage 0: Cancer cells are only in the ducts. Stage 0 breast cancer is another name for ductal carcinoma in situ.

Stage I: The tumor is small and hasn’t spread to your lymph nodes.

Stage II: One of these is true:

• The tumor is smaller than 20 millimeters (mm) and has spread to a few lymph nodes in your armpit (axillary lymph nodes).
• The tumor is 20 mm to 50 mm across and hasn’t spread to the axillary lymph nodes (stage IIA), or the tumor is 20 mm to 50 mm and has spread to the axillary lymph nodes (stage IIB).
• The tumor is larger than 50 mm and hasn’t spread to a few axillary lymph nodes.

Stage III: Cancer has spread to several lymph nodes. Cancer cells may also be in your chest wall or skin.

Stage IV: Cancer cells have spread to other parts of your body. Cancer can spread to all areas of your body, including your bones, lungs, liver or brain.

What are the treatments for male breast cancer?

Treatment depends on your cancer type and stage. Treatments include:

• Surgery: Breast cancer surgery is the most common treatment for early-stage breast cancer. Because men and people assigned male at birth have limited breast tissue, surgery to remove your entire breast (mastectomy) is more common than surgery to remove the lump only (lumpectomy). You may also need surgery to remove lymph nodes.
• Radiation therapy: Radiation for breast cancer uses targeted X-rays or other energy sources to kill cancer cells. Radiation usually follows surgery (typically a lumpectomy) to kill any remaining cancer cells.
• Chemotherapy (chemo): Chemotherapy uses drugs to kill cancer cells and stop tumors from growing. You may receive chemo treatments over several weeks or months. You may receive chemotherapy and radiation depending on the stage of the cancer and type of surgery. You won’t receive them at the same time, but rather one after the other.
• Hormone therapy: Providers use hormone therapy to lower estrogen levels or block their effects. You may receive this treatment if your cancer cells use hormones, like estrogen, to grow. Tamoxifen is a common medication used to treat male breast cancer.
• Targeted therapy: Targeted therapy treatments “target,” or interfere, with processes that allow cancer cells to grow. Targeted treatments only work on specific types of cancer cells. For example, some treatments only work on breast cancers with hormone receptors, while others only work on cancer cells with gene mutations, like BRCA1/2.

Can I prevent male breast cancer?

Male breast cancer isn’t preventable.

Still, talk to your healthcare provider if you have a family history of breast cancer. You may consider genetic testing to see if you have the BRCA1 or BRCA2 genetic mutation, which increases your risk. People with these gene changes should visit their healthcare provider regularly for frequent cancer screenings.

What is the outlook for men with breast cancer?

The biggest factors that affect your outlook are the tumor size, extent of cancer spread (reflected in the cancer stage) and features of the tumor (for example, hormone receptor status). Unfortunately, male breast cancer may spread to lymph nodes by the time a lump becomes noticeable.

Healthcare providers measure cancer outlook by the five-year survival rate. The survival rate for male breast cancer that hasn’t spread beyond the original tumor is 95%. The male breast cancer survival rate drops to 19% once the cancer has spread parts of your body away from your chest.

When should I see my healthcare provider about male breast cancer?

See your provider as soon as possible if you notice changes in your chest that may be signs of breast cancer. Early detection and treatment can greatly improve your prognosis.

If you’re at high risk for breast cancer, follow your healthcare provider’s advice about getting regular screenings. Early diagnosis and treatment make all the difference when it comes to living cancer-free following breast cancer treatment.

A note from Cleveland Clinic

Many men and people AMAB don’t think breast cancer can happen to them, so they may not recognize the signs. If you think something isn’t quite right with your chest tissue, see your healthcare provider for an evaluation. Early diagnosis and treatment have a significant impact on your long-term prognosis. Be honest with your provider about your symptoms and how long you’ve had them. If you have risk factors for breast cancer, talk to your provider about how to detect cancer in the early stages.