Selective intraoperative consultation for the evaluation of sentinel lymph nodes in breast cancer.

Background: Routine intraoperative evaluation of sentinel lymph nodes (SLNs) in breast cancer suffers from lack of sensitivity and consumes both time and resources. Failure to perform immediate consultation requires node-positive patients to return for delayed dissection.

Methods: We sought to determine whether selective use of intraoperative pathology consultation (IOC), based on the surgeon's clinical suspicion for metastases, would be accurate, avoid unnecessary consultations, and have a similar rate of delayed axillary dissection. We performed a retrospective chart review of two cohorts of clinically node-negative patients with invasive breast cancer undergoing axillary lymph node dissection (ALND). Selective pathology evaluation was performed in the study group and mandatory evaluation in the control group.

Results: The axillary basins of 327 patients undergoing routine IOC were compared with those of 91 patients in whom selective IOCs were requested. Twenty-eight consultations (31%) were obtained in the selective group. Selective consultation changed intraoperative management in 11 of 28 patients (39%) compared to 46 of 327 (14%) in the routine group (P = 0.005). The mean SLN metastasis size was 9.6 mm compared to 1.5 mm in patients in whom consultation was deferred (P = 0.003). The need for delayed ALND (17% vs. 14%) was similar in both groups, and was determined by occult metastases that were not detected by either method.

Conclusions: Selective use of IOC detects the majority of SLN macrometastases, avoids consultation that does not alter intraoperative management, and is not associated with an increased need for delayed ALND.