Estrogen and progesterone signal cell division. Why do women still get breast cancer after the menopause?

Question

What I mean is that tamoxifen and drugs try to cancel the effects of estrogen and progesterone. That shouldn't even be applicable to women past menopause!

Answer 1

estrogen and progesterone do a lot more than signal cell division.

not all breast cancers are estrogen sensitive. some are independent of hormone stimulation and can arise from a familial defect or acquired because of exposure to certain carcinogens.

Answer 2

cancer is bad

Answer 3

Scientists have identified two genes which are more likely to be defective in a breast cancer patient than someone without breast cancer.

These genes are also blamed for some other cancers.

However, even the two mutated genes are thought only to be responsible for approximately 5% to 10% of breast cancer cases.

Hormones seem to have an important role in breast cancer. Research has shown a link between levels of the female s*x hormone, oestrogen, and the risk of developing breast cancer.

Women who take certain types of hormone replacement therapy are at higher risk of breast cancer.

Women who have their first child later in life also appear to be at higher risk of developing breast cancer.

Tamoxifen blocks the female s*x hormone oestrogen. The hormone influences the growth of cells related to female reproduction, such as those in the breast or the uterus. If there is too much oestrogen in the system, cell growth can accelerate to the point where tumours start to develop. Tamoxifen competes with the s*x hormone for the same proteins - called receptors - found on the surface of cancer cells. When the drug locks onto the receptors it blocks the way for oestrogen - which would otherwise activate the cancer cell to divide and make the tumour grow.

Tamoxifen may cause cancer of the uterus (womb), strokes, and blood clots in the lungs. These conditions may be serious or fatal.