Adding a course of radiation to conventional surgery-plus-chemotherapy treatment may help improve the survival chances for women with advanced forms of breast cancer.

A new, long-term study shows that women at high risk of breast cancer (search) recurrence who received radiation after surgical removal of the breast (radical mastectomy) and chemotherapy had a 27 percent lower risk of death and 32 percent lower risk of breast cancer-related death 20 years after treatment.

Researchers say these results, combined with previous studies, confirm that in situations where the breast cancer has spread to more than four of the lymph nodes (search), chemotherapy alone after mastectomy is not optimal and that the addition of radiation therapy provides the best survival chances.

The results appear in the Jan. 19 issue of the Journal of the National Cancer Institute.

Radiation Reduces Breast Cancer Risks

In the study, researchers examined the effect of adding radiation therapy (targeted to the lymph nodes and chest wall) to a course of chemotherapy and radical mastectomy (search) in premenopausal women considered at high risk of breast cancer recurrence because the tumor had spread to four or more lymph nodes.

The 318 women in the study were originally treated between 1979 and 1986 in British Columbia, Canada, and followed for 20 years.

The results showed that women who received radiation and chemotherapy had better results on a variety of measures compared with women who received chemotherapy alone after mastectomy.

For example, women who received radiation along with chemotherapy had a 32 percent lower risk of breast cancer-related death and a 27 percent lower risk of death due to any cause compared with those who received chemotherapy alone. In addition, women who received radiation along with chemotherapy also had a lower risk of breast cancer recurrence.

Researchers say the long-term side effects from radiation were similar and acceptable for both groups of women. Previous studies had suggested that radiation might increase the risk of complications associated with heart-related deaths.

The results expand upon the 15-year follow-up of the women in this study, which showed that radiation therapy was associated with a lower risk of breast cancer survival but not a lower risk of death due to any cause.

Although the results suggest that adding radiation to chemotherapy and surgery is beneficial for high-risk breast cancer patients, experts say it may not be appropriate for women at lower risk of breast cancer recurrence or spread.

In an editorial that accompanies the study, Timothy Whelan and Mark Levine, MD, of the Juravinski Cancer Centre in Hamilton, Ontario, say additional studies are needed to determine the effectiveness of radiation in women at more moderate risk.

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCES: Ragaz, J. Journal of the National Cancer Institute, Jan. 19, 2005; vol 97: pp 116-126. News release, Journal of the National Cancer Institute.