“Approximately one-fourth of all patients who undergo initial breast-conservation surgery for breast cancer will have a subsequent operative intervention,” concluded a study published online by JAMA Surgery. “The rate of repeat surgeries varies by patient, tumor, and facility factors,” reported Lee G. Wilke, MD, of the University of Wisconsin, and colleagues.
Using the National Cancer Database, the researchers identified patients who were diagnosed with breast cancer at a Commission on Cancer–accredited center from January 1, 2004, through December 31, 2010. Patients who had an excisional biopsy were excluded, “because this cohort would be expected to have a higher-than-average repeat surgery rate,” the authors explained. “Patients who underwent neoadjuvant therapy were also excluded because of the variability in response to neoadjuvant therapy that could influence surgical choice.”
Among 316,114 patients with stage 0 to II breast cancer who underwent initial breast-conservation surgery, 241,597 patients (76.4%) had a single lumpectomy, and 74,517 (23.6%) underwent at least one additional operation. Among those having an additional operation, 46,250 (62.1%) underwent a completion lumpectomy, and 28,267 (37.9%) underwent a mastectomy.
“The proportion of patients undergoing repeat surgery decreased slightly during the study period, from 25.4% to 22.7% (P < .001),” the researchers reported. “Independent predictors of repeat surgeries were age, race, insurance status, comorbidities, histologic subtype, estrogen receptor status, pathologic tumor size, node status, tumor grade, facility type and location, and volume of breast cancer cases. Age was inversely associated with repeat surgery, decreasing from 38.5% in patients 18 to 29 years old to 16.5% in those older than 80 years (P < .001). In contrast, larger tumor size was linearly associated with a higher repeat surgery rate (P < .001).”
Repeat surgeries were most common at facilities in the Northeast region (26.5%) compared with facilities in the Mountain region (18.4%, P < .001). The rate for repeat surgeries was 26% at academic or research facilities vs 22.4% at community facilities (P < .001).
“At the root of the variability in repeat surgery rates for breast-conservation surgery is the lack of standardization of an acceptable margin width. The tumor margin width that will provide the lowest local recurrence rate has not been established in a randomized clinical trial setting,” the authors stated.
The data from their study can, the authors concluded, “be used to further support the vitally important adoption of guidelines regarding re-excision after initial breast-conservation surgery. Standard definitions of adequate margins, as set forth in the consensus guidelines by the Society of Surgical Oncology and the American Society for Radiation Oncology, and the indications for re-excision will decrease the wide variation in repeat surgery rates.”
Those consensus guidelines encourage “adoption of ‘no tumor on ink’ as the standard definition of a negative margin for invasive stage I and II breast cancer,” as noted in an accompanying editorial. Wilke et al “were unable to obtain exact pathologic margin width, but more than 92% of the patients had negative margins, indicating that a significant percentage of those undergoing additional operations had margins that were ‘negative on ink,” noted Julie A. Margenthaler, MD, of Washington University School of Medicine in St. Louis, and Aislinn Vaughan, MD, of Sisters of St. Mary’s Breast Care, St Charles, Missouri.
Calling for rapid adoption of the consensus guidelines, Drs. Margenthaler and Vaughn, stated: “We have robust evidence that additional operations for close, but negative, margins do not result in better outcomes. However, additional operations increase health-care costs, misuse of resources, patient anxiety, and delay in adjuvant therapy. With more than 200,000 new invasive breast cancers diagnosed each year, a staggering number of women are undergoing procedures that are unnecessary and simply wasteful.” ■