Ten Years of Tamoxifen Reduces Breast Cancer Risk and Improves Survival
Posted by on January 13, 2013 - 2:56pm

 Taking tamoxifen (Novaldex) for 10 years after primary treatment leads to a greater reduction in breast cancer recurrences and deaths than taking the drug for only 5 years according to findings from the ATLAS trial, which were presented at the San Antonio Breast Cancer Symposium.

Nearly 7,000 women with early-stage, estrogen-receptor positive breast cancer were enrolled in the trial between 1996 and 2005. After taking tamoxifen for 5 years, participants were randomly assigned to continue taking tamoxifen for another 5 years or to stop taking it.   Among the women who took tamoxifen for 10 years, the risk of breast cancer returning between 10 and 14 years after starting tamoxifen was 25 percent lower than it was among women who took it for 5 years, and the risk of dying from breast cancer was nearly 30 percent lower. Interestingly, the positive difference in outcome only emerged after the 10-year mark of taking the drug, and not between 5 -9+ years.

Tamoxifen can have side effects, including hot flashes, fatigue, and an increased risk of blood clots and endometrial cancer but there was no rise in the occurrence of these side effects for the women who took the drug for the extended period.  Women with a higher risk of their cancer returning long after adjuvant therapy ends, such as those whose cancers had infiltrated their lymph nodes or who had larger tumors, "will definitely be strong candidates for continuation of [tamoxifen] therapy," Dr Ravdin of the University of Texas Health Sciences Center at San Antonio, who moderated the press briefing said. But a woman at low risk of recurrence at any point "may very well rationally decide she doesn't want to take tamoxifen beyond 5 years”.

Both Pre-menopausal and Post-menopausal women could be candidates for this extended use of tamoxifen adjuvant therapy. It is important to consult with your doctor about the efficacy of this treatment for you.

~Cameron Phillips

NCI Cancer Bulletin December 12, 2012 vol 9 number 24

Can Topical Skin Gel Shrink Some Breast Cancer Tumors?
Posted by on July 5, 2011 - 10:00am

A clinical trial to see if a gel containing an active form of tamoxifen, an anti-estrogen therapy, can provide the drug's benefits with decreased risk of adverse health effects compared to those who take the oral tamoxifen is being conducted at Northwestern Medicine.

The new study drug is being tested on participants recently diagnosed with the earliest form of non-invasive breast cancer. Women who are treated for this kind of cancer (called ductal carcinoma in situ or DCIS) are usually advised to take oral tamoxifen for five years if their DCIS is hormone sensitive. In this research study, half the women receive the study gel and half the women receive the oral tamoxifen.

Tamoxifen, when taken as a pill for five years, reduces the risk of cancer recurrence in the same spot by a third and prevents the occurrence of half of new breast cancers. The therapy, however, has an increased risk of blood clots, uterine cancer and hot flashes. As a result, many women decline the treatment.

“The gel is a way to minimize exposure to the rest of the body and concentrate the drug in the breast where it is needed," said principal investigator Seema Khan, M.D., co-leader of the breast cancer program at the Robert H. Lurie Comprehensive Cancer Center of Northwestern University and a surgical oncologist at Northwestern Memorial Hospital. "Delivery of the drug through the skin of the breast means there will be very little drug circulating through the bloodstream and the body. This should reduce the possibility of blood clots."

Khan compared it to the current practice of delivering estrogen  via a skin patch to avoid the risk of blood clots. And because the circulating levels of the topical drug are very low, the gel should be unlikely to cause other side effects such as hot flashes and the increased risk of uterine cancer.

Another problem with oral tamoxifen is that it does not help all women who take it, because it needs to be activated in the liver by specific enzymes, and about a third of women lack these enzymes. These women may not receive full benefits from the pill, and the gel may be more effective for these women because the active form of the topical drug is being delivered directly into the breast tissue, noted Khan.

The participants in the trial must have a recent diagnosis of DCIS. In this form of breast cancer, abnormal cells multiply and form a growth within a milk duct. This form of cancer is noninvasive, meaning it hasn't spread from the milk duct to other parts of the breast.

Because of increased screening with mammograms, diagnoses of this early breast cancer have increased dramatically in recent years. While the cancer isn't life threatening when caught early, it requires treatment to prevent the condition from becoming invasive. Most women with this type of breast cancer are effectively treated with breast-conserving surgery and radiation.

The study is funded by the National Cancer Institute, and the study design has been approved by the FDA. Trial sites are at Northwestern University and Washington University. Participants will be randomized to take the tamoxifen pill or the active form of tamoxifen topical gel for six weeks prior to scheduled routine surgery. Researchers will measure the tumor growth rate to see if the reduction in growth rate is equally good in women who receive the gel and those who receive the pill.

Participants are currently being enrolled in the trial. For more information, visit http://www.cancer.northwestern.edu/toptam or call Katherine Page at k-page@northwestern.edu (312) 695-1408.

By Marla Paul