Does a breast cancer surgery patient's likelihood of enduring a second surgery, called reexcision, vary depending on her choice of hospital and surgeon, as opposed to her clinical profile? And could this lead to unnecessary surgeries?
Apparently, yes, according to a study of 2,206 patients by researchers who found substantial variation in four institutions in reexcision rates for patients who had negative specimen margins after the initial surgery.
The hospitals were not identified by result, but they included the University of Vermont and three health plans, Kaiser Permanente Colorado, Group Health of western Washington State and Marshfield Clinic of Wisconsin.
"Reexcision rates for patients with initial negative margins varied by institution, from a low of 1.7% ... at institution D, compared with 20.9% ...institution B." And among surgeons, the rate varied between 0% and 70%.
But whether that is a significant quality metric that should be studied for widespread adoption remains unclear, the researchers, led by Laurence McCahill, MD of the University of Michigan, wrote in their study, published in today's edition of the Journal of the American Medical Association.
However, the issue is a ripe candidate for provider comparison because one in four women with breast cancer who undergo partial mastectomy end up having another surgery to remove more potentially impacted tissue. And, "currently there are no readily identifiable quality measures that allow for meaningful comparisons of breast cancer surgical outcomes among treating surgeons and hospitals," the researchers wrote.
The researchers said that the issue of reexcision necessity is controversial, because "there is no current consensus on the appropriate distance required for a clear margin to be deemed adequate. Although the goal of reexcision is to further reduce the risk of breast cancer recurrence and mortality, the true benefit of reexcision remains undetermined."
It's a delicate balance. The surgeon wants to get as much cancerous tissue as possible while still preserving cosmetic appearance of the breast. But how much of a clear border should exist? Opinions differ, as do the needs and characteristics of each patient.
"Failure to achieve appropriate margins at the initial operation will require additional surgery with reexcision rate estimates ranging from 30% to 60%," producing "considerable psychological, physical and economic stress for patients and delay use of recommended adjuvant therapies," they wrote.
In an interview with the journal published online, McCahill was asked what factors might contribute to the wide variation. "The main things are probably technical factors, involving either the surgeon's technique or how the surgeon coordinates with the pathologist at the hospital. Have is the process and half is probably opinion." He added, "We need to get down to a more acceptable range of reexcision, down to 5% to 20% in the next 5 to 20 years."
Monica Morrow, MD, of the Department of Surgery at Memorial Sloan-Kettering Cancer Center in New York and Steven Katz, MD, at the Department of Medicine and Health Management and Policy at the University of Michigan, wrote an opposing editorial in the same issue saying that reexcision should not be used as a quality measure.
Legitimate clinical variables may drive the surgeon's decision to perform reexcision, including the method of pathological margin processing, quality of preoperative imaging, histological tumor type, and the patient's age, they said.
They agree that quality measures seem to have bypassed the field of breast cancer surgery. But they argued that if re-excision is used as a quality measure, surgeons may take more tissue unnecessarily just to play it safe.
But they say that surgeons and radiation oncologists share no consensus "as to what constitutes an optimal negative margin width because the question has not been addressed in prospective randomized trials."
"Perhaps the most important limitation of using reexcision as a quality measure is the potential consequences of its adoption," they wrote. It "raises the possibility that this information might be used to direct patients to different surgeons based on having the 'right rate.' "