Different types of hormonal therapy for breast cancer
What is Hormonal Therapy?
Hormonal therapy is a medical treatment that aims to change the way hormones affect the body in order to stop or slow the growth of cancer cells. It is mostly used in the treatment of breast cancer, since many forms of breast cancer are hormone-receptor positive. This means that the cancer cells are fueled by hormones, specifically estrogen and progesterone.
Hormonal therapy is usually recommended after surgery, to reduce the risk of recurrence. It can also be used to shrink tumors before surgery, or to control the growth of cancer that has spread to other areas of the body.
Types of Hormonal Therapy
There are several types of hormonal therapy available for breast cancer treatment. They include:
Selective Estrogen Receptor Modulators (SERMs)
SERMs are a class of drugs that work by binding to estrogen receptors in the body. This prevents estrogen from being able to stimulate the growth of cancer cells. The most commonly used SERM for breast cancer treatment is tamoxifen.
Tamoxifen is taken orally, usually for five years. It is effective in reducing the risk of recurrence for both pre- and post-menopausal women. It has also been shown to reduce the risk of breast cancer in women who are at high risk of developing the disease.
Selective Estrogen Receptor Downregulators (SERDs)
SERDs work in a similar way to SERMs, but they are more effective in blocking the effects of estrogen. They do this by binding to estrogen receptors in a way that causes them to break down and be removed from the body. The most commonly used SERD for breast cancer treatment is fulvestrant.
Fulvestrant is given as an injection into the muscle, usually once a month. It is used in post-menopausal women whose breast cancer has progressed despite treatment with other hormonal therapies.
Aromatase Inhibitors (AIs)
AIs work by blocking the production of estrogen in the body. They do this by inhibiting an enzyme called aromatase, which converts other hormones into estrogen. AIs are only effective in post-menopausal women, since pre-menopausal women still produce estrogen in their ovaries.
AIs are available as pills that are taken once a day. The most commonly used AIs for breast cancer treatment are anastrozole, letrozole, and exemestane. They are often used in combination with other hormonal therapies, or with chemotherapy.
Luteinizing Hormone-Releasing Hormone (LHRH) Agonists
LHRH agonists are drugs that stop the production of estrogen in pre-menopausal women. They do this by blocking the signals from the brain that stimulate the ovaries to produce estrogen. The most commonly used LHRH agonist for breast cancer treatment is goserelin.
Goserelin is given as an injection into the muscle, usually once a month. It is used in combination with other hormonal therapies or chemotherapy to treat pre-menopausal women with hormone-receptor positive breast cancer.
Combination Hormonal Therapy
Combination hormonal therapy involves using two or more types of hormonal therapy at the same time. This can be more effective than using a single therapy alone. The most common combination therapy is a SERM or SERD with an AI.
Side Effects of Hormonal Therapy
Like any medical treatment, hormonal therapy can have side effects. The most common side effects include hot flashes, mood swings, vaginal dryness, and joint pain. In some cases, hormonal therapy can also increase the risk of blood clots, stroke, and endometrial cancer.
Conclusion
Hormonal therapy is an important tool in the treatment of breast cancer. It can reduce the risk of recurrence, shrink tumors, and control the growth of cancer that has spread to other areas of the body. There are several types of hormonal therapy available, including SERMs, SERDs, AIs, and LHRH agonists. Combination therapy can also be used for more effective treatment. While hormonal therapy can have side effects, it is generally well-tolerated by most patients. If you have been diagnosed with breast cancer, talk to your doctor about whether hormonal therapy is right for you.