Breast Cancer Rates Falling May Be Due to Reduced Use of Hormone Replacement Therapy

December 15th, 2006

For the first time in years, breast cancer rates declined by more then 7% in 2003. The decline was greater in women 50 to 69, those most likely to use hormone replacement therapy (HRT). In those with estrogen-dependent types of tumors, the drop was 12%.

According to presenters at the recent San Antonio Breast Cancer Symposium, breast cancer was diagnosed in 14,000 fewer women than expected in 2003.

After the Women’s Health Initiative Study was stopped in July 2002 due to evidence of more risk than benefit of long-term HRT, many doctors urged post-menopausal women to go off their hormones. Within a year of this medical news, about half of the U.S. women who had been on HRT stopped their use.

Breast cancer had been steadily rising, about 2% annually, for decades. It is the most common major cancer in American women and the second leading cause of cancer deaths in women.  All U.S. cancer registries reporting to the federal government in 2003 showed a decline in their statistical information on this type of female cancer.

Researchers believe it possible that some breast cancers were already present, but that cutting off estrogen stopped their growth or caused them to shrink to an undetectable size. They also postulate that mammogram usage has been leveling off, thus contributing to the decline in cancer detection and smaller statistics. A trend toward lower-dose and shorter duration HRT could also have played a role.

Statistics from one year do not tell the entire story. It will take time to know whether breast cancer is truly on the decline and establishing a definite downward trend. Breast cancer might still be present in some menopausal women who abandoned HRT, but slower growing, taking longer to be detected.

In 2006, some 213,000 cases of breast cancer are expected in U.S. women, with over a million new cases worldwide.

Source:  CNN.com

Entry Filed under: Breast Cancer,CANCER,SENIORS HEALTH