Carcinoma of the Male Breast

Essentials of Diagnosis

» A painless lump beneath the areola in a man usually over 50 years of age.
» Nipple discharge, retraction, or ulceration may be present.

General Considerations
Breast cancer in men is a rare disease; the incidence is only about 1% of that in women. The average age at occurrence is about 60 - somewhat older than the most common presenting age in women. There may be an increased incidence of breast cancer in men with prostate cancer. The prognosis, even in stage I cases, is worse in men than in women. Blood-borne metastases are commonly present when the male patient appears for initial treatment. These metastases may be latent and may not become manifest for many years.

As in women, hormonal influences are probably related to the development of male breast cancer. There is a high incidence of both breast cancer and gynecomastia in Bantu men, theoretically owing to failure of estrogen inactivation by a liver damaged by associated liver disease. It is important to note that first-degree relatives of men with breast cancer are considered to be at high risk. This risk should be taken into account when discussing options with the patient and family. In addition, BRCA2 mutations are common in men with breast cancer. Men with breast cancer, especially with a history of prostate cancer, should receive genetic counseling.

Clinical Findings
A painless lump, occasionally associated with nipple discharge, retraction, erosion, or ulceration, is the primary complaint. Examination usually shows a hard, ill-defined, nontender mass beneath the nipple or areola. Gynecomastia not uncommonly precedes or accompanies breast cancer in men. Nipple discharge is an uncommon presentation for breast cancer in men, but is an ominous finding associated with carcinoma in nearly 75% of cases.

Breast cancer staging is the same in men as in women. Gynecomastia and metastatic cancer from another site (eg, prostate) must be considered in the differential diagnosis. Benign tumors are rare. Biopsy settles the issue.

Treatment
Treatment consists of modified radical mastectomy in operable patients, who should be chosen by the same criteria as women with the disease. Irradiation is the first step in treating localized metastases in the skin, lymph nodes, or skeleton that are causing symptoms. Examination of the cancer for hormone receptor proteins is of value in predicting response to endocrine ablation. Men commonly have ER-positive tumors. Adjuvant chemotherapy is used for the same indications as in breast cancer in women.

Because breast cancer in men is frequently a disseminated disease, endocrine therapy is of considerable importance in its management. Tamoxifen is the main drug for management of advanced breast cancer in men. Tamoxifen (20 mg daily) should be the initial treatment. There is little experience with aromatase inhibitors, though they should be effective. Castration in advanced breast cancer is a successful measure and more beneficial than the same procedure in women but is rarely used. Objective evidence of regression may be seen in 60-70% of men with hormonal therapy - approximately twice the proportion in women. The average duration of tumor growth remission is about 30 months, and life is prolonged. Bone is the most frequent site of metastases from breast cancer in men (as in women), and hormonal therapy relieves bone pain in most patients so treated. The longer the interval between mastectomy and recurrence, the longer the tumor growth remission following treatment. As in women, there is correlation between estrogen receptors of the tumor and the likelihood of remission following hormonal therapy.