Sentinel Lymph Node Frozen-Section Utilization Declines After Publication of American College of Surgeons Oncology Group Z0011 Trial Results With No Change in Subsequent Surgery for Axillary Lymph Node Dissection

OBJECTIVES: To evaluate use of sentinel lymph node (SLN) frozen section (FS) before and after publication of the Z0011 trial. METHODS: We identified 116 pre-Z0011 and 134 post-Z0011 patients from 18 months before and after Z0011-initiated changes. Clinicopathologic features were assessed by chart review. RESULTS: Post-Z0011 SLN FS use markedly declined when performed with breast-conserving therapy (BCT) (P < .0001), with SLN FS in 53 (73.6%) of 72 and 19 (25.0%) of 76 in pre- and post-Z0011 groups, respectively. There was post-Z0011 decline in axillary lymph node dissection (ALND) (P = .014) but no difference in later procedures for ALND. SLN positivity was associated with larger (≥1.6 cm) tumor size (P = .002). Nodal upstage was more frequent with invasive lobular (3/32; 9.4%) vs other invasive (2/188; 1.1%) subtypes. CONCLUSIONS: Our findings support reduced need for SLN FS for BCT patients post-Z0011. However, those with specific clinicopathologic features may derive greater benefit from SLN FS.