Hormonal Therapies
These drugs are used to inhibit certain cancers which are characterized by the presence of oestrogen receptors on target cells.
For breast cancer, they will only be given if the cancer is oestrogen receptor or progesterone receptor positive.
Selective estrogen receptor modulators (SERMS) – Tamoxifen, raloxifene
These are drugs that act by modulating activity of the oestrogen receptor
They can have both oestrogenic and anti-oestrogen effects depending on the tissue on which they are acting.
In the breast, SERMs inhibit oestrogen receptors, so inhibit proliferation of oestrogen-dependent cancers. Therefore, they are used in pre-menopausal women with metastatic breast cancer or those who are high risk
In the uterus, bone and liver, SERMs activate oestrogen receptors and so have oestrogenic effect
Side Effects
Menopausal symptoms (fatigue, hot flushes, night sweats, mood swings)
Abnormal vaginal bleeding or discharge
Increased risk of VTE
Increased risk of endometrial cancer (due to oestrogenic effects on endometrium)
Fulvestrant
This is an oestrogen receptor antagonist used to treat ER+ breast cancer
It is given once the breast cancer has spread to lymph nodes and breastbone
Aromatase inhibitors – Anastrozole, letrozole
These inhibit the aromatase enzyme which converts testosterone to oestrogen
They are used in postmenopausal women with ER-positive breast cancer.
Side Effects
Hot flushes
Osteoporosis
GnRH Analogs – Leoprolide, Goserelin
These are analogs that bind the GnRH receptor but over time inhibit LH and FSH secretion
This has downstream effects to decrease levels of testosterone and oestrogen
They are useful for treating prostate cancer (in men) and breast/ovarian cancer (women)
They are only given in pre-menopausal women who have ER+ or PR+ breast cancer
Side Effects
Gynaecomastia
Disclaimer
The intended purpose of this website is to be used as a resource for revision for exams. It should not be used as a guideline or reference for clinical practice/decision making or by patients looking for medical information or advice. In2Med takes no responsibility for any loss or damaged resulting from the use of information from this website.
