WEDNESDAY, Jan. 21, 2004 (HealthDayNews) -- Radiotherapy should routinely be considered as a treatment option after breast-conserving surgery for women diagnosed with early breast cancer, a new study says.
Researchers in Belgium say the procedure may reduce the chances of relapse and boost overall survival rates.
In a review of 15 studies in Europe, Canada and the United States, researchers found that when radiation was omitted, women were three times more likely to suffer relapses and faced a reduced chance of overall survival. The studies looked at recurrence rates for 9,422 women and mortality rates for 8,206 women.
Many of the studies showed women with early-stage breast cancer who have breast-conserving surgery followed by radiotherapy have similar survival rates as women who have a mastectomy. Moreover, they are also spared the disfiguration of losing a breast.
A team led by Dr. Vincent Vinh-Hung, a radiotherapist at the Oncology Center at Academic Hospital in Jette, Belgium, performed a pooled analysis of the randomized clinical trials of women with early-stage breast cancer who had breast-conserving surgery alone, or surgery followed by radiotherapy.
The study appears in the Jan. 21 issue of the Journal of the National Cancer Institute.
"Until now, almost all studies saw a reduction in relapse," Vinh-Hung says. "But now we think we are seeing the beginnings of an answer to the question of survival rates. We have been studying populations associated with radiotherapy, and are seeing better survival rates overall in Western countries."
The researchers calculated that, after eight years, omitting radiotherapy resulted in an 8.6 percent higher rate of unnecessary deaths. And for small tumors, it saw a positive survival rate of 1 percent to 3 percent in absolute terms in that same period.
In three clinical trials conducted in Canada and Denmark, the study saw a 9 percent to 10 percent improvement rate in overall survival in women who underwent radiotherapy following surgery.
"This is important because if there is no effect seen on survival, then the person with cancer might say, 'OK, I will wait,' and do a do-nothing strategy," says Vinh-Hung. "'I have 30 percent risk of relapse, so why not wait and then irradiate immediately if I relapse? If I do nothing, I have a two-thirds chance of no relapse.' So now on top of that we can add this little amount of knowledge to a do-nothing strategy. We are always looking for how to optimize treatment, so we can learn how to do better."
Radiotherapy is a highly localized daily therapy that begins after surgery to remove the tumor and lasts generally from 30 days to six weeks, but the procedure is not without drawbacks.
It can be a complex, extensive and labor-intensive procedure. Radiation also prolongs the length of treatment and has side effects that range from skin problems to breast hardening and heart and lung complications.
In an accompanying editorial, Drs. Katherine A. Vallis and Ian F. Tannock of Princess Margaret Hospital in Toronto noted that although there may be a small subset of women with good prognostic factors who do not need radiation after surgery, this analysis "reinforces the view that the large majority of patients undergoing breast-conserving surgery should also receive radiotherapy."
"The survival rate is a small advantage, really. But it is significant if you consider the number of women who have breast cancer in this country and elsewhere, it is quite a significant number of lives that could be saved," says Dr. Margaret F. Spittle, a consultant clinical oncologist at Middlesex Hospital and St. John's Centre for Diseases of the Skin. Spittle was familiar with some of the studies in the pooled analysis.