Breast Cancer Patients Take DNA Test to Determine Best...( SEATTLE Oct. 30 /- Nearly one thi...)

SEATTLE, Oct. 30 /PRNewswire/ -- Nearly one third of breast cancer patients prescribed tamoxifen currently fail treatment. According to the National Foundation for Cancer Research (NFCR), this failure rate can be reduced to less than ten percent, saving 20,000 lives each year, by having patients take a simple DNA test and properly managing their medications.

Recent research shows that tamoxifen has to be activated into endoxifen by the liver enzyme CYP2D6. Endoxifen is the medicine that prevents the recurrence of estrogen receptive positive cancers.

About ten percent of breast cancer patients prescribed tamoxifen are missing CYP2D6 because of their DNA, and will fail tamoxifen treatment. "Patients want to know that tamoxifen will definitely benefit them, before committing to take it for five years. DNA testing offers them the reassurance that their tamoxifen is effective," stated Dr. Michael Benjamin, oncologist and editor of the medical news website, InteractMD.com

Breast cancer patients can also fail tamoxifen treatment by unknowingly taking other prescription drugs, herbals preparations, or over-the-counter medicines that interfere with CYP2D6 activity. Many classes of drugs, including anti-depressants, prevent CYP2D6 from converting tamoxifen into endoxifen. That's why Genelex includes password-protected access to their GeneMedRx software program with each test. Patients enter all of the drugs they take and produce a report to learn if any of the drugs they take might be defeating their endoxifen treatment.

"Patients and physicians need to be aware that DNA testing for tamoxifen effectiveness is available now. There is typically a 10-year gap between research and application in the clinical setting. We need to shorten that time when people's lives are at stake -- as they are with tamoxifen," stated Genelex founder and CEO Howard Coleman.

For more information about the CYP2D6 DNA test, visit Genelex at