Focused Breast Cancer Radiation OK

Aug. 19, 2003 -- Delivering a more targeted dose of radiation directly to the tumor site may be just as effective as whole-breast radiation in preventing breast cancer from coming back in women with early-stage breast cancer.

Researchers say the new approach in breast-cancer radiation treatment may have the potential to reduce side effects and improve the outlook for women who have had their tumors removed with breast-conserving surgery. Breast-conserving surgery preserves as much as the breast as possible and is typically combined with other treatments such as radiation, which kills cancer cells. Radiation therapy is effective in reducing recurrences of breast cancer but sometimes damages normal cells as well.

A new study compares the effectiveness of the limited-field breast cancer radiation therapy versus the traditional whole-breast radiation method. It shows the two techniques are equally effective in preventing breast cancer recurrence after five years of follow-up.

The findings appear in the Journal of the National Cancer Institute.

Less Radiation, Same Results

Researcher Frank A. Vinci, MD, of the William Beaumont Hospital in Royal Oak, Mich., and colleagues say several clinical trials have shown that breast-conserving surgery plus radiation is just as effective as mastectomy (surgical removal of the entire breast) in women with early-stage breast cancer.

But they say it's not clear exactly how much tissue around the tumor site needs to be treated with radiation following breast-cancer surgery.

Researchers compared the rates of breast-cancer recurrence at the treatment site among 199 women treated with the limited-field breast cancer radiation and 199 women treated with whole-breast radiation therapy. Each of the groups was matched by age, tumor size, and other factors that might affect breast-cancer risk.

After five years of follow-up, researchers found no differences in the rates of local breast-cancer recurrence, time to recurrence, disease-free survival, overall survival, or development of other non-breast cancers.

Researchers say the results raise the question of whether whole-breast radiation therapy is necessary in certain low-risk breast cancer patients.

Long-Term Study Needed

In an editorial that accompanies the study, C. Norman Coleman, MD, and colleagues at the National Cancer Institute, say that long-term follow up of 10 years or more will be needed to determine if there are any late recurrences or other problems associated with this approach.

"Only by successfully completing a clinical trial on the equivalency of partial-breast irradiation with whole-breast irradiation can we provide definitive answers for those physicians and patients yet to face the decision about treatment options for early-stage breast cancer," they write.