CHICAGO, IL—Removing more tissue during a partial mastectomy could spare thousands of patients with breast cancer a second surgery, according to a study in the New England Journal of Medicine (2015; doi:10.1056/NEJMoa1504473) and presented at the 2015 American Society of Clinical Oncology (ASCO) Annual Meeting.
Breast cancer is diagnosed in nearly 300,000 women in the United States each year; more than half undergo breast-conserving surgery via a partial mastectomy to remove the disease. However, 20% to 40% of patients who undergo this procedure have positive margins, or cancer cells found at the edge of what was removed.
The presence of positive margins often leads to a second surgery to ensure that no cancer remains. The Yale Cancer Center study explored how removing more tissue all the way around the tumor site during the initial surgery, known as cavity shave margins (CSM), could reduce the need for a second surgery.
In this study of 235 patients with breast cancer ranging from stage 0 to stage III, surgeons performed a partial mastectomy as they normally would. Patients were then randomized in the operating room to either CSM or not.
“Despite their best efforts, surgeons could not predict where the cancer was close to the edge,” said the study’s lead author, Anees Chagpar, MD, MPH, associate professor of surgery (oncology) at Yale School of Medicine and director of The Breast Center at Smilow Cancer Hospital at Yale-New Haven.
“Taking cavity-shave margins cut the positive-margin rate in half, without compromising cosmetic outcome or increasing complication rates.”
Patients in the study will be followed for 5 years to evaluate the impact of the technique on recurrence rates.
“This randomized controlled trial has the potential to have a huge impact for breast cancer patients,” Chagpar said. “No one likes going back to the operating room, especially not the patients who face the emotional burden of another surgery.”