Breast Cancer Drug Helps Some and Hurts Others

Post-menopausal women under 55 benefit from tamoxifen breast cancer drug

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) For some women, tamoxifen can protect against the recurrence of breast cancer, but it can be hard figuring out which women will get the most from the drug while avoiding its serious side effects.

For a recent study, researchers set out to find which post-menopausal women would benefit the most and suffer the least from tamoxifen. They found that the benefits of taking the drug outweighed the negative effects in post-menopausal women under 55 years of age who have a greater risk of developing breast cancer.

dailyRx Insight: Tamoxifen offers the most beneifits to post-menopausal women under 55 years of age.

Tamoxifen can help prevent breast cancer, even years after treatment ends. However, its side effects - which include pulmonary embolism, endometrial cancer, deep vein thrombosis, and cataracts - often outweigh the benefits.

In order to determine which women tamoxifen would help the most, Peter Alperin, M.D., of Archimedes Inc., and colleagues conducted a virtual clinical trial on a simulated population of post-menopausal women under 55 years of age. They compared tamoxifen treatment to no treatment.

The researchers found tamoxifen has the most benefits and the least side effects in post-menopausal women under 55 years of age who have at least a 1.66 percent chance of developing breast cancer within 5 years.

According to Dr. Alperin, tamoxifen prevents 29 breast cancer cases and 9 breast cancer deaths for every 1,000 women treated with the drug. Furthermore, tamoxifen saves more than $47,000 for every 1,000 women treated in the United States.

The results of this study may help doctors and individual patients identify their best options for preventing breast cancer.

Cancer is diagnosed in over 12 million people each year, and kills over 7 million. It is the largest cause of death in the developing world, and one out of ever three people will be diagnosed with an invasive cancer at some point in their lifetime. Cancer is a group of diseases classified by abnormal and uncontrolled cellular growth in a particular organ or tissue type in the body. When the growth invades other tissues, causes damage to them, or spreads to different parts of the body it is considered malignant. Cancer is caused by a multitude of factors including genetics and infections, but a majority of cancers can be attributed to environmental causes, such as smoking, and being exposed to carcinogens or radiation. Symptoms of cancer are variable. In some cases, the cancer will produce symptoms that affect the organ it is located in, such as coughing and shortness of breath from a lung cancer, constipation and bloody stools from colon cancer, or headaches and cognitive problems from a brain cancer. Other cancers such as leukemia and blood cancers may produce flu-like symptoms and sudden infections. Some cancers may be discovered by a lump, or physical evidence, such as in breast cancer. Treatment for cancer is usually one of or a combination of surgery to remove it, radiation therapy, and chemotherapy. Newer treatments such as hormonal drugs and targeted drugs are making cancer treatment even more specific to the patient and the disease. Diagnosis is based off of physical examination and several imaging techniques such as MRI, PET scan, and laparoscopy. Definitive diagnosis is achieved when a pathologist examines a piece of cancerous tissue.

The study appears online in Cancer, a journal from the American Cancer Society.

Reviewed by: 
Review Date: 
March 14, 2011
Last Updated:
April 4, 2011