Aromatase inhibitors stop the production of estrogen in post-menopausal women. Aromatase inhibitors work by blocking the enzyme aromatase, which turns the hormone androgen into small amounts of estrogen in the body. This means that less estrogen is available to stimulate the growth of hormone-receptor-positive breast cancer cells.
Aromatase inhibitors can't stop the ovaries from making estrogen, so aromatase inhibitors only work in post-menopausal women.
There are three aromatase inhibitors:
- Arimidex (chemical name: anastrozole)
- Aromasin (chemical name: exemestane)
- Femara (chemical name: letrozole)
Each is a pill, usually taken once a day. Arimidex is the only aromatase inhibitor available in generic form.
Based on the results, most doctors recommend that after initial treatment (surgery and possibly chemotherapy and radiation therapy):
- an aromatase inhibitor is the best hormonal therapy to start with. When treating early-stage, hormone-receptor-positive breast cancer, aromatase inhibitors have more benefits and fewer serious side effects than tamoxifen.
- switching to an aromatase inhibitor after taking tamoxifen for 2 to 3 years (for a total of 5 years of hormonal therapy) offers more benefits than 5 years of tamoxifen.
- taking an aromatase inhibitor for 5 years after taking tamoxifen for 5 years continues to reduce the risk of the cancer coming back, compared to no treatment after tamoxifen.
-heart problem
-osteoporosis
-broken bones (jadi, kena buat bone density test to check ok!)
-joint stiffness/pain