Radiation therapy after a lumpectomy substantially reduces the risk of breast cancer recurrence. However, researchers have not come to a consensus about the most appropriate length of radiation therapy that a patient should receive. In the United States, radiation is delivered in smaller doses over a several weeks, but in the United Kingdom and Canada, larger doses of radiation are delivered over a shorter period of time.
To determine which strategy is most effective, Timothy Whelan, B.M., B.Ch., M.Sc., of the Hamilton Regional Cancer Centre in Ontario, and his colleagues compared breast cancer recurrence and cosmetic outcome among 1,234 women randomly assigned to receive either a more intensive course of radiation over 22 days or a less intensive regimen over 35 days. All of the women had undergone lumpectomies for invasive breast cancers that had not spread to the lymph nodes.
Nearly 6 years later, the shortened course did not result in increased recurrence of breast cancer or result in a worse cosmetic outcome. Local recurrence-free survival at five years was 97.2% in the group receiving a shorter course of therapy, compared with 96.8% in the group receiving an extended course of therapy. There was no difference in disease-free or overall survival. Further, the cosmetic outcome was similar and excellent or good in the majority of patients in both groups. Toxic effects from radiation, such as damage to the skin, were rare in both groups.
The authors note that these findings may have important implications. "A shorter fractionation schedule will lessen the burden of treatment for women, many of whom may also receive adjuvant chemotherapy, and will have important quality-
Contact: Linda Wang
Journal of the National Cancer Institute