Like chemotherapy, hormonal therapy is a systemic therapy—one that circulates through the bloodstream to attack cancer cells throughout the body.
Hormonal therapy works because hormones can affect the growth of some cancer cells. Reducing or stopping hormone production helps prevent the growth of these cancer cells in women whose cancers are hormone-receptor positive.
Hormonal therapy is sometimes used for endometrial stromal sarcoma (and not for other types of uterine sarcoma because it’s not effective against them). It’s used mainly if the cancer has metastasized, or spread, beyond the uterus or if the cancer has come back after earlier treatment.
Your doctor may suggest using one of these hormonal therapies to slow the growth of your cancer:
Progestins: These drugs are the main hormonal therapies for endometrial stromal sarcoma. They are like the hormone progesterone that occurs naturally in your body. The most common are medroxyprogesterone acetate (Provera) and megestrol acetate (Megace).
Tamoxifen: This drug helps prevent any estrogens that are circulating in your body from stimulating the growth of the cancer cells.
Aromatase inhibitors: If your ovaries have been removed (or no longer function), your body fat still makes estrogen. Drugs called aromatase inhibitors can stop this estrogen from being made. Examples of aromatase inhibitors include letrozole (Femara), anastrozole (Arimidex), and exemestane (Aromasin).
Gonadotropin-releasing hormone (GnRH) agonists: If you haven’t gone through menopause and your ovaries have not been not removed, you might get injections of these drugs to lower your estrogen levels. They turn off production of estrogen by your ovaries. Examples are goserelin (Zoladex) and leuprolide (Lupron).
Clinical trials are underway to evaluate the effectiveness of other hormonal therapies for endometrial stromal sarcoma.