Decline in Frozen Section Diagnosis for Axillary Sentinel Lymph Nodes as a Result of the American College of Surgeons Oncology Group Z0011 Trial

Abstract

Context.—Results of the American College of Surgeons Oncology Group Z0011 trial showed that patients with early-stage breast cancer and limited sentinel node metastasis treated with breast conservation and systemic therapy did not benefit from axillary lymph node dissection. Subsequently, most pathology departments have likely seen a decrease in frozen section diagnosis of sentinel lymph nodes. Objective.—To determine the effect of the Z0011 trial on pathology practice and to examine the utility of intraoperative sentinel lymph node evaluation for this subset of patients. Design.—Pathology reports from cases of primary breast cancer that met Z0011 clinical criteria and were initially treated with lumpectomy and sentinel lymph node biopsy from 2009 to 2015 were collected. Clinicopathologic data were recorded. Results.—Sentinel lymph node biopsies sent for frozen section diagnosis occurred in 22 of 22 cases (100%) in 2009 and 15 of 22 cases (68%) in 2010 during the pre-Z0011 years, and in 3 of 151 cases (2%) collected in 2011 through 2015, considered to be post-Z0011 years. Of the 151 post-Z0011 cases, 28 (19%) had sentinel lymph nodes with metastasis, and 147 (97%) were spared axillary lymph node dissection. Conclusions.—Following Z0011, intraoperative sentinel lymph node evaluation has significantly decreased at our institution. Prior to surgery, all patients had clinically node-negative disease. After sentinel lymph node evaluation, 97% (147 of 151) of the patients were spared axillary lymph node dissection. Therefore, routine frozen section diagnosis for sentinel lymph node biopsies can be avoided in these patients.