Radiotherapy improves survival after breast-conserving surgery

The omission of radiotherapy after breast-conserving surgery for early-stage breast cancer is associated with higher rates of relapse and a slightly higher mortality rate, according to a study in the January 21 issue of the Journal of the National Cancer Institute.

Many studies have shown that women with early-stage breast cancer who have breast-conserving surgery followed by radiotherapy have similar survival rates as women who have a mastectomy, and those women are also spared the disfiguration of losing their breast. However, radiotherapy prolongs the length of time that women are treated for breast cancer, the treatment can be costly, radiotherapy facilities are not common in all areas, and there are some side effects to radiotherapy.

For these reasons, several studies have examined the consequences of omitting radiotherapy from the treatment regimen. Vincent Vinh-Hung, M.D., of the Oncology Center at Academic Hospital in Jette, Belgium, and colleagues performed a pooled analysis of 15 randomized clinical trials of women with early-stage breast cancer who underwent breast-conserving surgery alone or surgery followed by radiotherapy. They analyzed recurrence rates based on information from 9,422 women, and mortality information was available for 8,206 women.

The authors calculated that the women who received breast-conserving surgery alone were three times more likely to have a relapse than women who had breast-conserving surgery followed by radiotherapy. (In clinical trials that had 5 or more years of follow-up information, the relapse rate ranged from 0.4% to 2.1% per year for women who received breast-conserving surgery and radiotherapy, compared with 1.4% to 5.7% per year among women who only had surgery.) The authors also calculated that the omission of radiotherapy resulted in an 8.6% relative excess of deaths.

“The present study confirms that radiotherapy should not be omitted after breast-conserving surgery, except for medical contraindications such as systemic vascular disease or a previous history of irradiation,” the authors conclude.

In an editorial, Katherine A. Vallis, M.D., Ph.D., and Ian F. Tannock, M.D., Ph.D., of Princess Margaret Hospital, Toronto, note that, although there may be a small subset of women with good prognostic factors who do not need to have radiotherapy after surgery, this analysis “reinforces the view that the large majority of patients undergoing breast-conserving surgery should also receive radiotherapy.”

Contacts:

Claire Verschraegen, University of New Mexico Cancer Research and Treatment Center, Albuquerque, 505-272-6760, cverschraegen@salud.unm.edu; Vincent Vinh-Hung, Oncology Center at Academic Hospital, Jette, Belgium, 32-2-477-6041, conrvhgv@az.vub.ac.be

Editorial: Vince Rice, Princess Margaret Hospital, 416-946-4501, ext. 5771; vince.rice@uhn.on.ca

Citations:

Vinh-Hung V, Verschraegen C, for the Breast Conserving Surgery Project. Breast-conserving surgery with or without radiotherapy: pooled-analysis for risks of ipsilateral breast tumor recurrence and mortality. J Natl Cancer Inst 2004;96:115–21.

Vallis KA, Tannock IF. Postoperative radiotherapy for breast cancer: growing evidence for an impact on survival. J Natl Cancer Inst 2004;96:88–9.

Note: The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Attribution to the Journal of the National Cancer Institute is requested in all news coverage.