If lab tests show that your tumor depended on your natural hormones to grow, it will be called estrogen-receptor-positive or progesterone-receptor-positive. Such tumors are often sensitive to anti-estrogen therapy, called hormonal therapy.
Hormone therapy is used to prevent the growth, spread, or recurrence of breast cancer by blocking your body's natural hormones from reaching any remaining cancer cells.
Incidence and Mortality
Estimated new cases and deaths from breast cancer (men only) in the United States in 2013:
New cases: 2,240.
Male breast cancer is rare. Less than 1% of all breast carcinomas occur in men.[3,4] The mean age at diagnosis is between 60 and 70 years, though men of all ages can be affected with the disease.
Predisposing risk factors  appear to include radiation exposure, estrogen administration, and diseases associated with hyperestrogenism,...
Hormone therapy includes using drugs that block the effects of estrogen or having a procedure that either removes the ovaries or makes them unable to produce hormones.
The estrogen-blocking drug tamoxifen is the most common and oldest of the hormonal therapy drugs. It has been shown to decrease the chance of recurrence in some early-stage cancers and to prevent the development of cancer in the opposite breast. Tamoxifen works by blocking estrogen from attaching to estrogen receptors on cancer cells. By blocking the estrogen receptors, it is believed that the growth of the cancer cells will be halted.
Tamoxifen is effective in pre- and postmenopausal women.
Other types of hormone therapy are called aromatase inhibitors. These drugs include anastrozole, letrozole, and examestane. They block the production of estrogen in the body, thus lowering the levels of the hormone in the blood. Aromatase inhibitors only work in postmenopausal women.
While on hormone therapy, continue to have yearly pelvic exams and Pap smears. Notify your doctor of any unusual bleeding or pain. The duration of treatment with tamoxifen or other anti-estrogen drugs should be discussed with your doctor.
Sometimes, a treatment called ovarian ablation is used to treat breast cancer. Ovarian ablation means making the ovaries of premenopausal woman nonfunctional, either by removing them with surgery or by using radiation therapy.
Another therapy is ovarian suppression. In this therapy, a drug is given that dries up the hormone that causes the ovaries to produce estrogen. Once this medication is discontinued, the estrogen production of the ovaries gradually returns. This therapy also is used in premenopausal women.