Since 2000, breast cancer cases have declines, but recently, the National Cancer Institute found that estrogen receptor-positive breast cancer have increased since 2003.
Estrogen receptor-positive breast cancer is the most common type of breast cancer. Alternatively, estrogen receptor-negative breast cancer rates have been declining since 1992. This decline can be attributed to better treatment options and earlier detection through the use of mammograms. More interesting, estrogen receptor-negative breast cancer is the most difficult to treat and can lead to death.
The differences in the rate of both kinds of cancer are not completely understood.
According to Fox News, hormone replacement therapies have been linked to overall decline in breast cancer rates. Drugs that are designed to block estrogen have decreased the growth of estrogen receptor-positive tumors, but do not show the same affect on estrogen receptor-negative tumors. Further research into breast is needed before any evidence can explain the differences in infection rates and effective treatment options.
This study is expected to be published in the Journal of National Cancer Institute.
