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Cancer of unknown primary

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Hormonal therapy for cancer of unknown primary

Hormonal therapy is a systemic therapysystemic therapyTreatment that travels through the bloodstream to reach cells all over the body. that slows the growth and spread of cancer of unknown primary (CUP) cells by changing hormone levels in the body. Hormones are chemical substances that are produced by glands in the body or made in a laboratory. Drugs, surgery or radiation therapy can be used to change hormone levels. Hormonal therapy is used occasionally to treat a cancer of unknown primary (CUP).

Hormonal therapy may be used when a CUP is thought to actually be a metastatic breast or prostate cancer. These cancers can grow in response to sex (reproductive) hormones (such as estrogen or androgens) in the body. Hormonal therapy may be used to slow the growth of the cancer or control symptoms of advanced breast or prostate cancer (palliative therapy).

The type of hormonal therapy used and the doses and schedules of drugs vary from person to person.

Types of hormonal therapy

The type of hormonal therapy used depends on where the cancer is thought to have started (primary site). Hormonal therapies either lower the level of the hormones in the body or prevent cancer cells from being able to use them.

Breast cancer

Breast cancer is usually suspected as the primary site when a woman has adenocarcinoma in the lymph nodes under the arm (axillary lymph nodes) or bone metastases. The doctor is most likely to give a woman hormonal therapy if test results show that the cancer is hormone-receptor positive. Breast cancers that are hormone–receptor positive contain estrogen or progesterone receptors and will likely respond to hormonal therapy.

Hormonal therapy for breast cancer may be offered and includes drugs like tamoxifen (Nolvadex, Tamofen) or an aromatase inhibitor.

Prostate cancer

A primary prostate cancer may be suspected in men with bone metastases.

Hormonal therapy for prostate cancer may be offered and includes drugs like luteinizing hormone-releasing hormone agonists (LHRH agonists) or antiandrogens. Surgery to remove the testicles (orchiectomy) may also be an option for some men.

For more detailed information on specific drugs, go to sources of drug information.

See a list of questions to ask your doctor about hormonal therapy.

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