June 8, 2009

Breast cancer patients take anti-oxidants

Many women with breast cancer take anti-oxidants while undergoing cancer treatment, even though the consequences are unknown, U.S. researchers learned.

The study, published online ahead of print of the July 15 issue of the journal Cancer, found almost 70 percent of the women used high doses of anti-oxidants, defined as higher than the amount contained in a Centrum multivitamin. Women who took high doses also were more likely to be using tamoxifen and to have a history of eating more fruits and vegetables, using herbal products and engaging in mind-body practices.

Heather Greenlee of the Columbia University Mailman School of Public Health in New York and colleagues said many breast cancer patients believe anti-oxidant supplements will protect them from the side effects of breast cancer treatment, help prevent recurrence of the disease and improve their overall health.

Greenlee's study is based on 764 patients who completed a follow-up interview and provided information on anti-oxidant supplement use.

Among these patients, 86.8 percent reported receiving chemotherapy, radiation or hormone therapy for breast cancer.

Given the common use of anti-oxidant supplements during breast cancer treatment, often at high doses and in conjunction with other complementary therapies, future research should address the effects of anti-oxidant supplementation on breast cancer outcomes, including whether anti-oxidants affect treatment toxicities, treatment efficacy, cancer recurrence and survival, the study authors said in a statement.