Surgeon acceptance of findings recommending against axillary lymph node dissection for breast cancer varied widely and appeared more common among high-volume surgeons in multidisciplinary practices, according to survey results published in JAMA Oncology.
The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial found that among women with node-negative breast cancer and metastases in one or two sentinel nodes, there were no major differences in locoregional recurrence, DFS or OS following breast-conserving surgery with whole-breast irradiation whether they were randomly assigned to axillary lymph node dissection or to sentinel node biopsy alone.
“Although new treatments with small incremental benefits are often embraced by the medical community, studies supporting the use of less therapy have been adopted more slowly,” Monica Morrow, MD, FACS, chief of breast service at Memorial Sloan Kettering Cancer Center, and colleagues wrote.
Several studies offer high-quality evidence that axillary lymph node dissection is not required for women with sentinel lymph node metastases, the researchers continued, “but little is known about current surgeon attitudes toward axillary lymph node dissection and acceptance of omission of axillary lymph node dissection in patients meeting clinical trial eligibility criteria.”
Morrow and colleagues conducted a survey of 488 surgeons responsible for treating a population-based sample of women with early-stage breast cancer (n = 5,080) from July 1, 2013, to Aug. 31, 2015. The researchers categorized surgeons as having low, selective or high propensities for axillary lymph node dissection, as identified by their responses to five different clinical scenarios.
Three hundred seventy-six surgeons (77%) responded to the survey, and 359 (mean age, 53.7 years; 73.7% men) provided complete information on axillary lymph node dissection.
One hundred forty-two surgeons (37.8%) treated 20 or fewer cases of breast cancer each year, whereas 108 (28.7%) treated more than 50 each year.
Nearly half of surgeons (49%; n = 175) recommended axillary lymph node dissection in the instance of one macrometastasis.
Among surgeons considered low propensity, just one (1.1%) approved axillary lymph node dissection in response to any nodal metastasis, compared with 69 (38.1%) selective surgeons and 85 (95.5%) high-propensity surgeons (P < .001).
A lower propensity for axillary lymph node dissection was significantly associated with higher breast cancer treatment volume (21-50: 0.19; 95% CI, 0.39 to 0.02; >51: 0.48; 95% CI, 0.71 to 0.24; P<.001).
Lower propensity also was associated with recommendation of a minimal margin width (1 mm-5 mm: 0.1; 95% CI, 0.43 to 0.22; no ink on tumor: 0.53; 95% CI, 0.82 to 0.24; P < .001), as well as participation in a multidisciplinary tumor board (1% to 9%: 0.25; 95% CI ,0.55 to 0.05; > 9%: 0.37; 95% CI, 0.63 to 0.11; P = .02) and SEER site (0.18; 95% CI, 0.35 to 0.01; P = .04).
More stringent strategies may be required in addition to educational efforts directed toward low-volume surgeons suggested by the researchers, Sara H. Javid, MD, assistant professor of medicine at the University of Washington School of Medicine, Seattle, and Benjamin O. Anderson, MD, professor of surgery and global health medicine, also at University of Washington, wrote in an accompanying editorial.
“In this evolving era of specialty-specific maintenance of board certification by the American Board of Surgery, an opportunity exists to introduce the concept of adherence to quality metrics, such as the omission of axillary lymph node dissection in the setting of sentinel lymph node metastases, as performance benchmarks upon which surgeons will be evaluated,” Javid and Anderson wrote. “With increased visibility of one’s own performance relative to peers and evidence-based standards of practice, combined with the support of a respected credentialing body, such as the American Board of Surgery, toward the delivery and measurement of care, meaningful change is plausible.” – by Andy Polhamus
Disclosures: The authors report no relevant financial disclosures. Javid and Anderson report no relevant financial disclosures.