Tamoxifen Reported to Cause Aggressive Cancer Tumors
8-28-2009 by: Melanie Grimes, citizen journalist
The cancer prevention drug, tamoxifen, may cause cancer. It has been reported that rare cancers are being found in long-term users. Tamoxifen is the drug of choice, prescribed after breast cancer detection or surgery. Its use is deemed to have a 20% success rate in preventing further incidences of cancer. For this reason, many breast cancer survivors are long term users of tamoxifen, and this news is disturbing for both them and their caregivers.
Tamoxifen is an estrogen-blocking drug. The tumors that developed in the tamoxifen users were rare but aggressive. Some suggest that the risks still outweigh the downside, because tamoxifen is so successful at preventing a recurrence of common breast tumors.
Many question the report and its methodology, which is the typical reaction from the medical community to bad news. And this is especially bad news, as tamoxifen is a staple in the fight against cancer.
The report about tamoxifen was not based on a research study, but only on observation. However the observation was made at the esteemed Fred Hutchinson Cancer Research Center in Seattle, WA, a center long known for comprehensive scientific research and reporting. The report was published in Cancer Research. According the Dr. Li, the author of the report, long term tamoxifen usage increases risk by four-fold for a more aggressive, difficult-to-treat type of cancer in the breast opposite, or contralateral, to the initial tumor.
This report follows previously published findings by Dr. Li in 2001, in which the same findings were reported. At that time, Dr. Li found a fivefold increased risk of estrogen-receptor (ER)-negative breast cancers in breast cancer survivors taking tamoxifen. The 2001 study contained 9,000 women over the age of 50. They were followed from 1990 and 1999. All of the women lived in Western Washington State and this study was the first population-based study that looked at the estrogen-receptors in contralateral (opposite side of the body) breast tumors.
The use of tamoxifen has been shown to reduce by 20% the ER-positive contralateral breast cancers - the most common type. This type of cancer is found in two-thirds of the cases diagnosed. Now that findings show a 500% increase in of estrogen-receptor (ER)-negative breast cancers, breast cancer survivors and their caregivers should assess the risks versus benefits and perhaps seek alternative treatments.
New research in the area of homeopathy and botanical medicine shows promise for both cancer prevention and cancer relapse, without the side effects known to be triggered by tamoxifen and other drugs. It is hoped that research in these fields will fill the need for cancer prevention in coming years.