Faslodex® (There may be other brand names for this medication)
How is it Administered?
Your medication will be given by intramuscular (IM) injection, usually into a large muscle in the buttocks. It is usually given once a month.
What is it Used For?
This drug is used to treat hormone receptor positive breast cancer in postmenopausal women and in women whose breast cancer has worsened after being treated with anti-estrogen medications such as tamoxifen.
How Does it Work?
Cancer is a group of diseases in which abnormal cells divide without control. In some cancers, the presence of a particular hormone may cause the tumors to grow. For example, the presence of estrogen causes some types of breast cancers to grow.
Hormone therapy may be used in a few different ways to fight hormone- dependent cancers. First, it can block your body’s ability to make the hormone. Second, it can stop the hormone produced from attaching to receptors on the cancer cells. Lastly, it can act as a substitute and bind itself to the estrogen receptors on a cell, which prevents estrogen from entering the cancer cells.
Fulvestrant is an estrogen receptor antagonist; it works by the third method, substitution. It attaches itself to the (estrogen) receptors on the cells and causes the receptor to break down. This blocks the effects of estrogen on the cancer cells, and tumor growth can slow or stop.