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Encyclopedia of Health and Medicine

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hormone-driven cancers Types <strong>of</strong> cancer that<br />

thrive on or require hormones for their survival.<br />

In men, ANDROGENS (notably TESTOSTERONE) sustain<br />

PROSTATE CANCER. In women, ESTROGENS <strong>and</strong> PROGES-<br />

TERONE feed many types <strong>of</strong> BREAST CANCER, OVARIAN<br />

CANCER, <strong>and</strong> ENDOMETRIAL CANCER (cancer <strong>of</strong> the<br />

UTERUS).<br />

Hormone-driven cancers arise in cells that are<br />

HORMONE dependent. However, researchers do not<br />

know whether hormones cause these cancers to<br />

develop or simply fuel them after they form.<br />

Researchers do know that breast cancer <strong>and</strong> ovarian<br />

cancer occur more <strong>of</strong>ten in women who have<br />

extended exposure to estrogen, such as with early<br />

onset <strong>of</strong> MENSTRUATION (MENARCHE before age 12) or<br />

late MENOPAUSE (after age 55). The use <strong>of</strong> oral contraceptives<br />

(birth control pills) or hormone<br />

replacement therapy (HRT) for menopause may<br />

also increase a woman’s risk for these cancers,<br />

though research continues to investigate these<br />

connections.<br />

The correlation between hormones <strong>and</strong> cancer<br />

becomes even less distinct with prostate cancer.<br />

Researchers know that testosterone fuels the<br />

growth <strong>of</strong> prostate cancer cells once the cancer<br />

develops. But the role <strong>of</strong> testosterone in the development<br />

<strong>of</strong> prostate cancer is unknown. Unlike<br />

estrogen <strong>and</strong> progesterone levels in women,<br />

testosterone levels in men are fairly constant<br />

though do decline gradually after age 30. Some<br />

researchers believe it is lower testosterone levels<br />

that allow prostate cells to mutate, becoming cancerous.<br />

Other researchers believe the changing<br />

balance between estrogen <strong>and</strong> testosterone in a<br />

man’s body as he ages plays a contributing role.<br />

Hormone-driven cancers in men <strong>and</strong> women are<br />

more likely after age 50.<br />

HORMONE THERAPY as adjuvant therapy is the<br />

st<strong>and</strong>ard <strong>of</strong> care for most hormone-driven cancers.<br />

Primary treatment may be surgery to remove the<br />

tumor, RADIATION THERAPY, or CHEMOTHERAPY, or a<br />

mix <strong>of</strong> any or all <strong>of</strong> these treatment options.<br />

Oncologists use luteinizing hormone–releasing<br />

hormone (LHRH) agonists, which suppress the<br />

body’s production <strong>of</strong> <strong>and</strong>rogens <strong>and</strong> estrogens, to<br />

treat prostate cancer in men <strong>and</strong> breast, ovarian,<br />

<strong>and</strong> endometrial cancers in women. Aromatase<br />

inhibitors, which block the body’s ability to convert<br />

<strong>and</strong>rogens to estrogen, <strong>and</strong> tamoxifen, which<br />

binds with estrogen receptors to block estrogen,<br />

are among the hormone therapies oncologists use<br />

to treat hormone-driven breast cancers in women.<br />

See also CANCER TREATMENT OPTIONS AND DECI-<br />

SIONS; IMMUNOTHERAPY.<br />

hyperplasia Overgrowth <strong>of</strong> cells. Hyperplasia,<br />

also called hypertrophy, may occur for various<br />

reasons. Though the overgrowth <strong>of</strong> tissue may<br />

cause symptoms it is not necessarily cancerous.<br />

For example, BENIGN PROSTATIC HYPERPLASIA (BPH) is<br />

common in men over age 65 <strong>and</strong> commonly<br />

causes symptoms such as difficult URINATION.<br />

Endometrial hyperplasia is similarly common in<br />

women approaching MENOPAUSE, causing symptoms<br />

such as abnormal uterine bleeding. Typically<br />

the structure <strong>of</strong> cells <strong>and</strong> tissue in hyperplasia is<br />

normal; there is simply an overgrowth. The risk is<br />

that hyperplasia will progress to abnormal cells<br />

<strong>and</strong> tissue structure, a precancerous condition<br />

called DYSPLASIA. Unless it causes symptoms,<br />

hyperplasia does not require treatment other than<br />

diligent monitoring.<br />

See also CANCER RISK FACTORS; CELL STRUCTURE AND<br />

FUNCTION.<br />

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