As the name suggests, Selective estrogen receptor modulators, modulate the estrogen effect in the breast tissue. More specifically they block the effect by sitting in the receptor of estrogen on the cell surface. As the estrogen receptors are occupied by the SERMs, estrogen is not able to attach itself to the cancer surface as a result of which the cells are not able to receive growth stimulation.
Other mass and tissue in the body, also contain estrogen receptors namely bones and the uterus. Depending the kind of cell, estrogen receptor structure varies. Thus receptors of uterus, bones and breasts each differ from one another. SERMs as the name suggests are selective and only attach themselves to breast cancer cells. Thus only inhibiting their growth and not affecting multiplication of other cells.
→ Tamoxifen (Also called Tamoxifen Citrate; Brand Name: Nolvadex)
→ Evista (Chemical Name: Raloxifene)
→ Fareston (Chemical Name: Toremifene).
All three SERMs are taken orally and are available as pills, usually the course is one pill a day. Of all three, tamoxifen is the most commonly known and prescribed SERM.
To compare aromatase inhibitors with tamoxifen for assessing in post menopausal women the better regiment in treatment of early-stage, hormone-receptor-positive breast cancer a number of studies have been conducted, Because tamoxifen is the most commonly used SERM.
Post initial therapy, the best hormonal therapy of the three medication type available an aromatase inhibitor is the best hormonal therapy. As compared to tamoxifen, aromatase inhibitors are more effective in treatment of early-stage, hormone-receptor-positive breast cancer. It has lesser serious side effects.
A 5 year course of tamoxifen has fewer benefits than a course of aromatase inhibitors for 2-3 years after a 2 -3 year course of tamoxifen. ( A total of 5 years of hormonal therapy).
After a 5 year tamoxifen course as compared to no treatment; a 5 year aromatase inhibitor 5 year course considerably reduces the recurrence risk.
SERM medication: tamoxifen is most suited for hormone-receptor-positive breast cancer in premenopausal women.