All About Male Breast Cancer
What is the breast?
The breast is a collection of fatty tissue located on the chest wall. The male breast includes blind ducts that sit just below the nipple and areola. There are also blood and lymph vessels throughout the male breast.
What is male breast cancer?
Collections of cells that are growing abnormally or without control are called tumors. Tumors that do not have the ability to spread throughout the body may be referred to as benign. They are not thought of as cancerous. Tumors that have the ability to grow into other tissues or spread to distant parts of the body are referred to as malignant. Malignant tumors within the breast are called breast cancer. Theoretically, any of the types of tissue in the breast can form a cancer, but most male breast cancers are ductal carcinomas (formed in the ducts).
Sometimes, precancerous cells may be found within the breast tissue. These are referred to as ductal carcinoma in-situ (DCIS) or lobular carcinoma in-situ (LCIS). These types of tumors are very rare in men.
What causes male breast cancer and am I at risk?
There are about 2,670 cases of male breast cancer diagnosed annually. Age is a risk factor in men for the development of breast cancer. The average age of men diagnosed with breast cancer is 68. African-American men have a higher incidence of male breast cancer.
The risk of breast cancer is also increased in men with a family history of breast cancer. Other risk factors for the development of male breast cancer include Klinefelter's syndrome (a congenital condition in which men are born with a Y chromosome and at least 2 X chromosomes), men from families with known BRCA 1 and 2 mutations, being of Jewish descent, mumps orchitis (swelling of the testes caused by the mumps virus), estrogen treatment, obesity, liver disease, radiation exposure, and heavy alcohol consumption.
What screening tests are available?
Because male breast cancer is so rare, routine screening is not recommended. Men should be familiar with the appearance of their breasts and report any changes in size, lumps or redness, puckering of the skin or nipple discharge to their health care providers.
Men who are at higher risk for male breast cancer should receive education and perform breast self-exams and have a clinical breast exam with their provider annually beginning at the age of 35.
What are the signs of male breast cancer?
The most common presenting symptom in men is a mass/lump in the breast. Other signs of male breast cancer include nipple discharge (particularly if bloody), nipple retraction and skin ulceration. Breast cancer can spread to the lymph nodes around the underarm, neck, and chest, even if a primary mass is not felt in the breast. These symptoms do not always signify the presence of breast cancer, but they should always be evaluated by a healthcare professional. You should report any lumps, bumps or other symptoms to your healthcare provider.
How is male breast cancer diagnosed?
Your healthcare provider may order a diagnostic mammogram if you have symptoms of breast cancer. However, mammograms may be difficult to perform in men, particularly men who are thin. Another diagnostic test that may be used is a breast ultrasound. An ultrasound uses high-frequency sound waves to outline the suspicious areas of the breast. It is painless and can often distinguish between benign and malignant lesions.
Depending on the results of the mammogram and/or ultrasound, your provider may recommend that you have a biopsy. A biopsy is the only way to know for sure if you have cancer because it allows your providers to get cells that can be examined under a microscope.
There are different types of biopsies; they differ with regard to how much tissue is removed. Some biopsies use a very fine needle, while others use thicker needles or even require a small surgical procedure to remove more tissue. Your provider will decide which type of biopsy you need depending on the appearance of the breast mass.
Once the tissue is removed, a pathologist will review the specimen. The pathologist can tell if the cells are cancerous or not. If the tumor does represent cancer, the pathologist will describe what type of tissue it arose from, how abnormal it looks (known as the grade), whether or not it is invading surrounding tissues, and whether or not the entire lump was removed during surgery. The pathologist will also test the cancer cells for the presence of hormones (estrogen, and progesterone) and HER-2 receptors. The presence of estrogen and progesterone receptors are important because cancers that have these receptors can be treated with hormonal therapies. HER-2 expression may help predict prognosis and allow for treatment with therapies directed specifically at HER-2. See Understanding Your Pathology Report for more information.
How is male breast cancer staged?
Male breast cancer is staged in the same manner as female breast cancer.
In order to guide treatment and offer some insight into prognosis, breast cancer is staged into five different groups. This staging is done in a limited fashion before surgery, considering the size of the tumor on a mammogram and any evidence of spread to other organs that is found with other tests. It is done again after surgery when the pathologist can look at the entire specimen and lymph nodes to look for signs of cancer. The staging system is very complex. A simplified version is described below. The entire staging system is outlined at the end of this article.
- Stage 0: (called carcinoma in situ/non-invasive breast cancers) These are very rare in men.
- Lobular carcinoma in situ (LCIS) refers to abnormal cells lining a gland in the breast. This is a risk factor for the future development of cancer, but this is not felt to represent a cancer itself.
- Ductal carcinoma in situ (DCIS) refers to abnormal cells lining a duct. Treatment options are similar to patients with Stage I breast cancers.
- Stage I: early-stage breast cancer where the tumor is less than 2 cm and hasn't spread beyond the breast.
- Stage II: early-stage breast cancer in which the tumor is either less than 2 cm across and has spread to the lymph nodes under the arm; or the tumor is between 2 and 5 cm (with or without spread to the lymph nodes under the arm), or the tumor is greater than 5 cm and hasn't spread outside the breast.
- Stage III: locally advanced breast cancer in which the tumor is greater than 5 cm across and has spread to the lymph nodes under the arm; or the cancer is extensive in the underarm lymph nodes; or cancer has spread to lymph nodes near the breastbone or to other tissues near the breast.
- Stage IV: metastatic breast cancer in which cancer has spread outside the breast to other organs in the body.
Depending on the stage of your cancer, your provider may want additional tests to determine whether cancer has spread to any organs outside of the breast and surrounding lymph nodes. Nearly all individuals with a breast cancer diagnosis will need a chest x-ray and basic blood work. If you have stage III cancer, your provider may recommend other tests, such as CT scan and bone scan. Each case is unique, and your providers will determine what is necessary to adequately stage your cancer.
How is male breast cancer treated?
Treatment of male breast cancer is similar to the treatment of female breast cancer. Treatments for breast cancer vary based on individual factors, including the cancer stage, the age and overall health of the patient, and the findings in your pathology report.
Treatment for Early/Moderate Stage Breast Cancer
Generally speaking, early/moderate-stage breast cancer refers to breast cancer that is stage 0-II. These cancers are less than 5 centimeters, can be removed surgically, and have not spread beyond the breast and regional lymph nodes.
Mastectomy, or total removal of the breast, is the recommended surgery in most men with breast cancer. Breast-conserving surgery (partial mastectomy/lumpectomy) may be an option for older men with other health issues or those who are interested in nipple preservation and can tolerate radiation therapy.
Many patients will also have a surgical procedure to remove lymph nodes from the axilla (armpit). This may be a sentinel lymph node biopsy, where 1-2 lymph nodes are removed, or an axillary dissection, where many more nodes are removed. The pathologist will review both the breast tissue removed during the surgery and the lymph node tissue that is removed. They will communicate with your surgeon and other providers regarding the type of cancer cells that are seen, as well as the size of the cancer, and the number of lymph nodes that have cancer in them. These factors will help to determine what further treatment may be needed.
Even when tumors are removed by surgery, microscopic cancer cells can spread to distant sites in the body. In order to decrease a patient's risk of the cancer returning (called recurrence), many breast cancer patients are offered chemotherapy. Chemotherapy is the use of anti-cancer medicines that go throughout the entire body to eliminate cancer cells that have broken off from the breast tumor and spread. Many factors go into determining whether an individual patient should have chemotherapy. Generally, patients with higher stage disease need chemotherapy; however, chemotherapy can be beneficial even for patients with early-stage disease. Individual factors such as age, overall health, and biologic properties of the breast tumor go into decisions regarding whether or not chemotherapy will provide a benefit. In some cases, the genetic makeup of the tumor may be used to determine the potential benefit of chemotherapy. OncoType Dx may be used to evaluate the need for chemotherapy in men.
There are a number of different chemotherapies, and they are usually given in combinations for 3 to 6 months before and/or after surgery for early/moderate stage breast cancer. Most chemotherapies used for breast cancer are given by IV, so they need to be given in an oncology clinic/infusion center. Medications that are commonly used in early/moderate stage breast cancer treatment include adriamycin (doxorubicin), cyclophosphamide, taxanes (taxol and taxotere), methotrexate, and 5-FU. There are advantages and disadvantages to each of the different regimens that your medical oncologist will discuss with you. Based on your own health, your cancer, the molecular testing results, and side effects you wish to avoid, you can work with your providers to come up with the best regimen for you.
Men who have had breast-conserving surgery for an early/moderate stage breast cancer may be offered radiation therapy. However, radiation is not frequently used in the treatment of male breast cancer. Radiation therapy refers to the use of high energy x-rays to kill cancer cells. Radiation therapy is recommended for nearly all early-stage breast cancer patients who have breast-conserving surgery. Radiation is important in reducing the risk of local recurrence. Your radiation oncologist can answer questions about the utility, process, and side effects of radiation therapy in your particular case.
Treatment for Advanced Breast Cancer
Locally advanced (stage III) breast cancers are usually treated with a modified radical mastectomy and dissection of the lymph nodes under the arm. Some patients will be given chemotherapy prior to surgery to shrink the tumor making it easier to remove. Stage IV tumors are not generally treated with surgery.
The term "advanced breast cancer" means that the cancer cells have spread beyond the original tumor into lymph nodes, the tissue surrounding the tumor or other areas of the body. In some cases, the cancer cells cannot be seen on radiology scans, but we suspect they may be traveling through the blood and lymphatic systems. In stage IV (metastatic) disease, these cells typically form tumors that can be seen on radiology scans and/or cause problems or symptoms for the patient. For this reason, the treatment for patients with advanced breast cancer must be "systemic" – meaning it can travel throughout the body. Systemic treatments include chemotherapy, hormone therapy and targeted therapies, including those targeting HER2 receptors. Surgery and radiation are local treatments, as they can only treat a specific area.
Treatment of advanced breast cancer varies from patient to patient. It requires discussion between patient and oncologist and consideration of many factors, including hormone receptor and HER2 status, prior treatments, the patient's other health conditions, goals of treatment, and balancing quality of life with treatment side effects. Your oncologist may prescribe one chemotherapy agent or a combination of agents. Sometimes a certain combination of medications will be given for several cycles. If they appear not to work or to stop working, your provider may recommend that the combination of medications be changed. Your provider may also give you a chemotherapy break if you have severe side effects from the medications.
There are many different chemotherapy medications, which can be given alone or in various combinations. Many chemotherapy medicines used for breast cancer are given through a vein, so they need to be given in an oncology clinic, although some can be given by mouth, in the form of a pill.
Some of the standard chemotherapy agents that are used in the treatment of breast cancer include adriamycin (doxorubicin), cyclophosphamide, methotrexate, taxanes (taxol and taxotere), capecitabine, fluorouracil, vinorelbine, eribulin, carboplatin, epirubicin, and ixabepilone.
If you experience bone metastases, you may also receive medications to prevent further damage to the bones and reduce bone pain. These medications include denosumab (Xgeva®), pamidronate (Aredia) and zoledronic acid (Zometa).
Radiation therapy is the use of high-energy x-rays to kill cancer cells. There are many ways that radiation therapy may be used for patients with advanced breast cancer. Some patients require radiation therapy to the breast or the chest wall after a modified radical mastectomy. Some patients having this treatment will also require radiation to the axilla (armpit) or supraclavicular (lower neck) regions. This radiation can be given at the same time as radiation to the breast or chest wall and is given with the goal of killing any cancer cells that may be in the patient's lymph nodes. Generally, this radiation will require the patient to come for radiation treatments 5 days a week for 5-6 weeks. The radiation treatments themselves are painless, but skin irritation and fatigue can develop as the radiation course goes on.
Radiation in patients with advanced/metastatic breast cancer may also be palliative focused. This means the treatment is to relieve symptoms and quality of life. Palliative radiation therapy often targets an area where the cancer has metastasized such as the brain, bones or spine.
Hormonal and Targeted Therapy in Early and Advanced Breast Cancer
When the pathologist examines a tumor specimen, he or she may determine that the tumor is expressing estrogen and/ or progesterone receptors. Patients whose tumors express estrogen receptors are candidates for therapy with estrogen-blocking drugs. Estrogen-blocking medications include tamoxifen and a family of medications called aromatase inhibitors (anastrozole, letrozole, exemestane). If you are unable to take tamoxifen, you may be offered an aromatase inhibitor in combination with another medication called a GnRH analog. These medications are taken for 5 - 10 years after breast cancer surgery. Hormone therapy has been shown to reduce your risk of recurrence if your tumor expresses estrogen receptors. These medications may cause side effects. When taking tamoxifen, patients may experience weight gain, hot flashes, and mood swings. Taking tamoxifen may also increase the risk of serious medical issues, such as blood clots and stroke.
Men taking aromatase inhibitors may experience bone or joint pain and are at increased risk for thinning of the bones (osteopenia or osteoporosis). Men taking aromatase inhibitors should have bone density testing prior to starting treatment and periodically based on results and may require treatment for bone thinning.
HER-2 is a receptor that is over-expressed in about 25% of all breast cancers but is less common in male breast cancers. These are referred to as HER2 positive breast cancers. These tumors may grow faster and are more likely to spread, but there are also medications designed specifically to target the HER2 protein, giving these tumors an extra treatment option. The most common treatment for HER2 positive cancers is trastuzumab (Herceptin®), which may be given to treat the cancer or prevent it from recurring. In addition, lapatinib (Tykerb®), pertuzumab (Perjeta®), neratinib (Nerlynx), ado-trastuzumab emtansine (Kadcyla) and fam-trastuzumab deruxtecan-nxki also treat HER2 positive cancers.
Male breast cancers are more likely to be hormone receptor-positive (HR+). Treatments used in the treatment of HR+ male breast cancers include abemaciclib (Verzenio ®), palbociclib (Ibrance®), and ribociclib (Kisqali®).
Olaparib (Lynparza®) is another targeted therapy, called a PARP inhibitor, that can be used in men with breast cancer who also have a BRCA mutation. Alpelisib (Piqray®) is a PI3K inhibitor, another type of targeted therapy. It is estimated that 30-40% of all breast cancers have a mutation of the PIK3CA gene, but this mutation is less common in men. Your care team will test you for this mutation to determine if you are a candidate for treatment with this medication.
Clinical trials are extremely important in furthering our knowledge of this disease. It is through clinical trials that we know what we do today, and many exciting new therapies are currently being tested. Talk to your healthcare provider about participating in clinical trials in your area. You can also explore currently open clinical trials using the OncoLink Clinical Trials Matching Service.
Follow-up Care and Survivorship
Once you have been treated for breast cancer, you will need to be closely followed for a recurrence. At first, you will have follow-up visits every 3-6 months. The longer you are free of disease, the less often you will have to go for checkups. After 5 years, you may only see your provider once a year. Men do not need routine mammograms after treatment. Your bone density should be assessed after completion of treatment and then every 2 years if you are receiving hormone therapy. Men who have had a breast cancer diagnosis should also have genetic counseling and testing.
Fear of recurrence, the financial impact of cancer treatment, employment issues, and coping strategies are common emotional and practical issues experienced by breast cancer survivors. Your healthcare team can identify resources for support and management of these practical and emotional challenges faced during and after cancer.
Cancer survivorship is a relatively new focus of oncology care. With some 17 million cancer survivors in the US alone, there is a need to help patients transition from active treatment to survivorship. What happens next, how do you get back to normal, what should you know and do to live healthy going forward? A survivorship care plan can be a first step in educating yourself about navigating life after cancer and helping you communicate knowledgeably with your healthcare providers. Create a survivorship care plan today on OncoLink.
Resources for More Information
Male Breast Cancer Coalition
Shares stories from male breast cancer survivors and resources.
His Breast Cancer Awareness
Created to assist men and their caregivers and family with coping with male breast cancer. Offers resources and education.
After Breast Cancer Diagnosis
Provides free, personalized information and one-to-one support to people affected by breast cancer – patients, families, and friends.
A nonprofit organization dedicated to providing the most reliable, complete, and up-to-date information about breast cancer.
Living Beyond Breast Cancer
Provides support and education for patients, family members, and healthcare professionals.
Appendix: Complete Breast Cancer Staging
Stage Information for Breast Cancer (AJCC Staging System 8th Edition 2016)
Primary tumor cannot be assessed
No evidence of primary tumor
Carcinoma in situ
Ductal carcinoma in situ
Paget’s disease of the nipple NOT associated with invasive carcinoma and/or carcinoma in situ (DCIS and/or LCIS) in the underlying breast parenchyma. Carcinomas in the breast parenchyma associated with Paget’s disease are categorized based on the size and characteristics of the parenchymal disease, although the presence of Paget’s disease should still be noted
Tumor less than or equal to 20mm or less in greatest dimension
Tumor less than or equal to 1mm in greatest dimension
Tumor greater than 1mm but less than or equal to 5mm in greatest dimension
Tumor greater than 5mm but less than or equal to 10mm in greatest dimension
Tumor greater than 10mm but less than or equal to 20mm in greatest dimension
Tumor greater than 20mm but less than or equal to 50mm in greatest dimension
Tumor greater than 50mm in greatest dimension
Tumor of any size with direct extension to the chest wall and/or to the skin (ulceration or skin nodules).
Extension to the chest wall, not including only pectoralis muscles adherence/invasion
Ulcerations and/or ipsilateral satellite nodules and/or edema (including peau d’orange) of the skin, which do not meet the criteria for inflammatory carcinoma
Both T4a and T4b
Lymph Node (N) Clinical
Regional lymph nodes cannot be assessed.
No regional lymph node metastasis
Metastases to movable ipsilateral level I, II axillary lymph node(s)
Metastases in ipsilateral level I, II axillary lymph nodes that are clinically fixed or matter; or in clinically detected ipsilateral internal mammary nodes in the absence of clinically evident axillary lymph node metastases
Metastases in ipsilateral level I, II axillary lymph nodes fixed to one another or to other structures.
Metastases only in clinically detected ipsilateral internal mammary nodes and in the absence of clinically evident I, II axillary lymph node metastases
Metastases in ipsilateral infraclavicular (level III axillary) lymph node(s) with or without level I, II axillary lymph node involvement; or in clinically detected ipsilateral internal mammary lymph node(s) with clinically evident level I, II axillary lymph node metastases; or metastases in ipsilateral supraclavicular lymph node(s) with or without axillary or internal mammary lymph node involvement
Metastasis in ipsilateral infraclavicular lymph node(s)
Metastasis in ipsilateral internal mammary lymph node(s) and axillary lymph node(s)
Metastasis in ipsilateral supraclavicular lymph node(s)
Lymph Node (N) Pathologic
Regional lymph nodes cannot be assessed
No regional lymph node metastasis histologically
No regional lymph node metastases histologically, negative IHC
Malignant cells in regional lymph nodes no greater than 0.2mm
No regional lymph node metastases histologically, negative molecular findings
Positive molecular findings, but not regional node metastases detected by
Micrometastases; or metastases in 1-3 axillary lymph nodes and/or internal mammary nodes with metastases detected by sentinel lymph node biopsy but not clinically detected
Micrometastases greater than 0.2mm but not greater than 2.0mm
Metastases in 1-3 axillary lymph nodes, at least one metastases greater than 2.0mm
Metastases in internal mammary nodes with micrometastases or macrometastases detected by sentinel lymph node biopsy but not clinically detected
Metastases in 1-3 axillary lymph nodes and in internal mammary lymph nodes with micrometastases or macrometastases detected by sentinel lymph node biopsy but not clinically detected
Metastases in 4-9 axillary lymph nodes or in clinically detected internal mammary lymph nodes in absence of axillary node metastases
Metastases is 4-9 axillary nodes with at least one tumor deposit greater than 2mm
Metastases in clinically detected internal mammary lymph nodes in the absence of axillary lymph node metastases
Metastases in ten or more axillary lymph nodes; or in infraclavicular (level III axillary) lymph nodes; or in clinically detected ipsilateral internal mammary lymph nodes in the presence of one or more positive level I, II axillary lymph nodes; or in more than three axillary lymph nodes and in internal mammary lymph nodes with micrometastases or macrometastases detected by sentinel lymph node biopsy but not clinically detected; or in ipsilateral supraclavicular lymph nodes
Metastases in ten or more axillary lymph nodes (at least one tumor deposit greater than 2.0 mm); or metastases to the infraclavicular (level III axillary lymph) nodes
Metastases in clinically detected ipsilateral internal mammary lymph nodes in the presence of one or more positive axillary lymph nodes; or in more than three axillary lymph nodes and in internal mammary lymph nodes with micrometastases or macrometastases detected by sentinel lymph node biopsy but not clinically detected
Metastasis in ipsilateral supraclavicular lymph nodes
Distant Metastases (M)
No evidence or radiologic evidence distant metastases
No clinical or radiographic evidence of distant metastases, but deposits of molecularly or microscopically detected tumor cells in circulating blood, bone marrow, or other non-regional nodal tissue that are no larger than .2mm in a patient without symptoms or signs of metastases
Distant detectable metastases as determined by clinical and radiographic means and/or histologically proven larger than .2mm
Any histologically proven metastases in distant organs; or if in non-regional nodes, metastases greater than 0.2 mm
After a T stage, N stage, and M stage has been defined, these factors are put together to determine the overall cancer stage:
Histologic grade (Invasive)
GX: Grade cannot be assessed
G1: Low combined histologic grade
G2: Intermediate combines histologic grade
G3: High combined histologic grade
Histologic Grade (DCIS-Nuclear Grade)
GX: Grade cannot be assessed
G1: Low nuclear grade
G2: Intermediate nuclear grade
G3: High nuclear grade
In situ Carcinomas
Ductal carcinoma in situ
Not otherwise specified (NOS)
Medullary with lymphoid stroma
Papillary (predominantly micropapillary pattern)
Paget’s disease and infiltrating
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