Intraoperative frozen section sentinel node assessment for breast cancer metastases: lessons learned from the implementation of a new protocol

• Published in: Pathology Vol. 42; p. S68
• Main Authors: Brown, Shaun, Ireland-Jenkin, Kerryn
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2010
• ISSN: 0031-3025; 1465-3931
• DOI: 10.1097/01268031-201042001-00142

Intraoperative assessment of sentinel nodes in breast cancer is an emerging procedure wherein diagnosis of nodal metastases potentially avoids a second procedure for axillary clearance. Imprint cytology and frozen section have been utilised in many centres.1–3 In July 2007, after a review of the literature, 1–3 our centre commenced a protocol using combined macroscopic and frozen section examination of sentinel nodes. The protocol was modified in January 2008, utilising what was learned from an audit of the initial six months. This study reviews the intraoperative assessment results for 2008 (51 patients), and compares them to the final histopathology reports. The overall sensitivity was 53% with specificity 100%. Sensitivity was 72% for macrometastases and 20% for micrometastases. By all modalities, micrometastases are difficult to diagnose intraoperatively. However, frozen section examination can be used successfully for macrometastases. It is a quick method and importantly yielded no false positives at our centre. Some macrometastases can be subtle and are often better identified with palpation rather than visualisation. Some histological patterns are difficult to diagnose at frozen section and caution should be taken to avoid false positives. Minimal cutting into tissue is paramount to avoid tissue loss.