Tamoxifen Treatment Could Be Extended To Ten Years
December 6, 2012

New Study Recommends Ten Year Treatment Of Tamoxifen

Connie K. Ho for redOrbit.com — Your Universe Online

Researchers from the University of Oxford recently revealed a study which showed that prolonged use of tamoxifen could help breast cancer from returning. Tamoxifen has been used in the past as daily treatment for female patients with breast cancer in remission. The study could impact the current recommendations for the treatment, which is five years for female patients.

The findings of the study were recently revealed at the annual San Antonio Breast Cancer Symposium and published in the medical journal The Lancet. The study consisted of over 6,800 women from some 36 countries. For some women tamoxifen delayed tumor growth, for others it appeared to help prevent tumor growth.

"This trial is great news for women with this type of breast cancer as it suggests that taking the commonly used drug, tamoxifen, for longer could save more lives with minimal additional side effects," commented Dr. Caitlin Palframan, head of policy at Breakthrough Breast Cancer in the United Kingdom, in an article by BBC News.

A report by ABC News states that the study first began in 1996 and it is considered one of the largest clinical trials on breast cancer. For approximately two-thirds of patients that have tumors sensitive to estrogen, tamoxifen is the pill to take as it blocks estrogen. Based on the findings, female patients who took tamoxifen for a decade reduced their risk of death from breast cancer by almost half. The researchers stated that women who discovered tumors early on and took tamoxifen over ten years reduced their risk of death from breast cancer by another 29 percent, compared to women who stopped taking the pill after five years. As well, 12 percent of women who took tamoxifen for 10 years died five to 1 years after breast cancer diagnosis, as compared to 15 percent of women who took tamoxifen for five years and were diagnosed with breast cancer five to 14 years prior.

"Five years of adjuvant tamoxifen is already an excellent treatment that substantially reduces the 15-year risk for recurrence and death," the study´s author Dr. Christina Davies, senior research fellow at the University of Oxford, wrote in a statement to ABC News. "We now know that 10 years of tamoxifen is even better, approximately halving breast cancer mortality during the second decade after diagnosis"

Even though the study showed positive results, there are also risks to taking tamoxifen. For some patients, doubling the length of treatment results in double the risk of developing endometrial cancer to approximately three percent; this type of cancer can impact the uterine lining. Uterine cancer is considered to be treatable, and death rates are low with approximately 0.4 percent of patients who took tamoxifen for 10 years died because of endometrial cancer.

Patients have also spoken out about the side effects of the treatment and their thoughts on the treatment.

"Patients get very nervous when they stop any hormonal therapy, because they feel like now they aren't doing anything," Lillie Shockeny, a breast cancer survivor an administration director of the Johns Hopkins Cancer Survivorship Program, told USA Today. "The opportunity to 'do something' might be appealing, despite the side effects."

According to The New York Times, breast cancer specialists unaffiliated with the study believe that it could have a great impact for premenopausal women; postmenopausal women generally have different drug regimens.

“We´ve been waiting for this result,” noted Dr. Robert W. Carlson, a professor at the Stanford School of Medicine with past clinical investigations in breast cancer, in The New York Times article. “I think it is especially practice-changing in premenopausal women because the results do favor a 10-year regimen.”

Some medical experts have touted the findings.

"This important study adds further clarity to the question about the length of time women should take tamoxifen,” remarked Martin Ledwich, a representative of Cancer Research UK, in the BBC News article. "Although treatment for hormone receptor positive breast cancer has become more complex in recent years with some women receiving aromatese inhibitors, these results will help in deciding the length of treatment for women who are prescribed tamoxifen alone."

On the other hand, there have been mixed results to the findings of the study as discussion arises on the risks versus benefits.

"The data may push more patients to consider longer durations of anti-estrogen therapy," noted Dr. Harold Burstein, an associate professor of medicine at Harvard Medical School and a physician at Brigham and Women´s Hospital, in the ABC News article. "Patients will also need to be aware of the trade-offs, including mild side effects and more serious but rare cancer risks."