Male breast cancer is a relatively rare cancer in men that originates from the breast. As it presents a similar pathology as female breast cancer, assessment and treatment relies on experiences and guidelines that have been developed in female patients. The optimal treatment is currently not known.

About one percent of breast cancer develops in males. The tumor can occur over a wide age range, but typically appears in men in their sixties and seventies. Known risk factors include radiation exposure, exposure to female hormones ( estrogen), and genetic factors. High estrogen exposure may occur by medications, obesity, or liver disease, and genetic links include a high prevalence of female breast cancer in close relatives. Male BRCA mutation carriers are thought to be at higher risk for breast cancer.

As in females, infiltrating ductal carcinoma is the most common type. While intraductal cancer, inflammatory carcinoma, and Paget's disease of the nipple have been described, lobular carcinoma in situ has not been seen in men.

Size of the lesion and lymph node involvement determine prognosis; thus small lesions without lymph node involvement have the best prognosis. Estrogen receptor and progesterone receptor status and HER2/neu gene amplification need to be reported as they may affect treatment options. About 85% of all male breast cancers are estrogen receptor???positive, and 70% are progesterone receptor???positive.

Typically self-examination leads to the detection of a lump in the breast which requires further investigation. Other less common symptoms include nipple discharge, nipple retraction. swelling of the breast, or a skin lesion such as an ulcer. Ultrasound and mammography may be used for its further definition. The lump can be examined either by a needle biopsy where a thin needle is placed into the lump to extract some tissue or by an excisional biopsy where under local anesthesia a small skin cut is made and the lump is removed. Not all palpable lesions in the male breast are cancerous, for instance a biopsy may reveal a benign fibroadenoma. In a larger study from Finland the average size of a male breast cancer lesion was 1.8 cm.

Male breast cancer can recur locally after therapy, or can become metastatic .

Staging

In addition to TNM staging surgical staging for breast cancer is used; it is the same as in female breast cancer and facilitates treatment and analysis.

• Stage I refers to invasive breast cancer with the tumor not exceeding 2 cm and absence of lymph node involvement.

• Stage II describes to invasive breast cancer when the tumor is either 2 cm or less and the local armpit (axillary) lymph nodes are involved (Stage IIA), or the tumor is 2???5 cm in size with local lymph node involvement (Stage IIB), or greater than 5 cm without lymph node involvement (Stage IIB).

• Stage III is divided into three subcategories:

• *In IIIA there is breast cancer with axillary lymph nodes clumped together or attached to other structures.

• *In IIIB the tumor has spread to the chestwall or skin, and may have involved lymph nodes of the axilla and/or breastbone.

• *In IIIC the tumor has spread to the chest wall or skin and lymph nodes below or above the collar bone are affected.

• Stage IV is applied to metastatic breast cancer; typically lungs, liver, bone, or brain are involved.

There are significant differences between male and female breast cancer. Lesions are easier to find in men due to the smaller breast size, however, lack of awareness may postpone seeking medical attention. The presence of gynecomastia may mask the condition. The diagnosis is made later in men???at age 67 on average???than in women with their average at 63. Indeed, almost half of male breast cancer patients are stage III or IV.

Treatment largely follows patterns that have been set for the management of postmenopausal breast cancer. There are no controlled studies in men comparing adjuvant options. In the vast majority of men with breast cancer hormone receptor studies are positive, and those situations are typically treated with hormonal therapy.

Locally recurrent disease is treated with surgical excision or radiation therapy combined with chemotherapy. Distant metastases are treated with hormonal therapy, chemotherapy, or a combination of both. Bones can be affected either by metastasis or weakened from hormonal therapy; bisphosphonates may be used to counterbalance this process and strengthen bones.

Chemotherapeutic and hormonal options in male breast cancer

Chemotherapeutic options include:

• cyclophosphamide plus methotrexate plus fluorouracil (CMF).

• cyclophosphamide plus doxorubicin plus fluorouracil (CAF).

• Trastuzumab ( monoclonal antibody therapy).

Hormonal options include:

• Orchiectomy.

• Gonadotropin hormone releasing hormone agonist ( GNRH agonist) with or without total androgen blockage ( anti-androgen).

• Tamoxifen for estrogen receptor???positive patients.

• Progesterone.

• Aromatase inhibitors.

Adjusted for age and stage the prognosis for breast cancer in men is similar to that in women. Prognostically favorable are smaller tumor size and absence or paucity of local lymph node involvement. Hormonal treatment may be associated with hot flashes and impotence.