“Our study provides critical interim companion data to awaited randomized trials and may help clinicians and patients quantify the risk-benefit ratio of brachytherapy compared with standard therapy,” Benjamin D. Smith, MD, said of a study comparing lumpectomy and either whole-breast irradiation or brachytherapy as treatment for invasive breast cancer in older women.
“Having some of these data and putting the two treatments side-by-side enables us to show people some of the differences in complications and in mastectomy rates,” said Dr. Smith. “That can be the basis upon which you can have a conversation with your patients about some of the tradeoffs.”
What Are the Tradeoffs?
The study found that over 5 years, women receiving brachytherapy were more likely to have subsequent mastectomies, 4.0% vs 2.2% for those receiving whole-breast irradiation.
Brachytherapy was also associated with a higher risk of postoperative skin or soft-tissue infections, experienced within year 1 by 16.2% treated with brachytherapy compared with 10.3% treated with whole-breast irradiation. Noninfectious postoperative complications occurred among 16.3% of patients treated with brachytherapy compared to 9.0% of patients treated with whole-breast irradiation.
Five-year overall survival was essentially the same—87.7% vs 87.0% for patients treated with whole-breast irradiation.
“Compared with [whole-breast irradiation], brachytherapy irradiates less breast tissue and requires a much shorter course of treatment,” the researchers reported in the JAMA study. “I have some patients for whom the convenience of radiation therapy is the most important aspect of the choice in treatment they’ll receive, and those patients often end up receiving some type of partial-breast radiation strategy, either brachytherapy or noninvasive external-beam approaches to finish radiation therapy in a week,” Dr. Smith said.
“There are other patients who would much prefer to have the treatment that is potentially associated with the very best long-term tumor control or has the very best long-term randomized data demonstrating its safety and effectiveness. Those patients typically choose some type of whole-breast irradiation,” he continued.
“I think it would be overly paternalistic for us to look at these small differences and then make a sweeping value judgment to say that all patients should receive this or all patients should receive that. But I do think these data will be helpful in contextualizing some of the tradeoffs between the two different treatments and then helping patients decide what is most important to them.”
What About Younger Women?
The study involved only women aged 67 years or older. In addition, a consensus statement on partial-breast irradiation published by the American Society for Radiation Oncology (ASTRO) in 2009 defined suitable patients for brachytherapy as those aged 60 years and older and “recommends being cautious about using brachytherapy for women between the ages of 50 and 60,” Dr. Smith said. In the JAMA article, the authors noted that future studies are required “to validate findings in younger patients with other insurance status.” ■