According to results published in the Journal of the American Medical Association, use of Nolvadex® (tamoxifen) or Evista® (raloxifene) to reduce breast cancer risk results in generally similar quality of life, although sexual function may be better with Nolvadex.

Breast cancer causes roughly 40,000 deaths annually in the U.S. alone. The majority of women with breast cancer have cancer that is estrogen receptor-positive (ER-positive). This type of breast cancer is stimulated to grow by the female hormones estrogen and/or progesterone.

Some postmenopausal women at a high risk of developing breast cancer can be treated with the anti-estrogen agent Nolvadex. In high-risk women, Nolvadex reduces the risk of breast cancer by approximately 50%. This reduced risk of breast cancer, however, is accompanied by an increased risk of conditions such as endometrial (uterine) cancer and blood clots.

Evista is an agent that also reduces the stimulatory effects of estrogen on cancer growth. It is approved for the prevention and treatment of osteoporosis. However, due to the fact that it reduces estrogen’s effects on cells, researchers speculated that it may also be used as a preventive or therapeutic agent for ER-positive breast cancer.

Researchers conducted a clinical trial, referred to as the STAR trial (The NSABP Study of Tamoxifen and Raloxifen [STAR] P-2 Trial), to directly compare Evista to Nolvadex in the prevention of breast cancer in women who were considered at high risk of developing the disease. The trial enrolled over 19,000 women who have been followed for just under four years. The results of the trial suggest that Evista is as effective as Nolvadex in reducing the risk of invasive breast cancer in high-risk postmenopausal women, and carries a lower risk of blood clots and cataracts.

To compare the effects of Nolvadex and Evista on patient-reported quality of life, researchers collected quality-of-life information from a subset of participants in the STAR trial. Information was collected from close to 2,000 women.

• There were no significant differences between women in the Nolvadex group and women in the Evista group in physical and mental health or depression.
• Women in the Nolvadex group reported better sexual function.
• Women in the Nolvadex group were more likely to report gynecologic problems, symptoms such as hot flashes, leg cramps, and bladder control problems.
• Women in the Evista group were more likely to report musculoskeletal problems, pain during intercourse, and weight gain.

The researchers conclude that Nolvadex and Evista, when used for reducing the risk of breast cancer in high-risk postmenopausal women, result in similar overall patient-reported physical and mental health.

Evista is not currently approved for prevention or treatment of breast cancer.

Reference: Land SR, Wickerham DL, Costantino JP et al. Patient-reported Symptoms and Quality of Life During Treatment with Tamoxifen or Raloxifene for Breast Cancer Prevention: The NSABP Study of Tamoxifene and Raloxifene (STAR) P-2 Trial. Journal of the American Medical Association. 2006;295:2742-2751.

Related News:

Nolvadex® and Evista® Similarly Effective at Preventing Invasive Breast Cancer (6/12/2006)

Evista® as Effective as Tamoxifen in Preventing Breast Cancer with Fewer Side Effects (4/18/2006)