Can interpectoral nodes be sentinel nodes?

Background: This study was designed to determine if interpectoral nodes could be sentinel nodes for some breast cancers. Methods: Thirty-five consecutive breast cancer patients undergoing axillary node dissection had a dissection of the interpectoral nodes. These were sent to pathology as a separate specimen. Results: Three patients were identified with isolated interpectoral nodal metastasis. Conclusion: In upper quadrants or deep breast cancers the interpectoral nodes may be the earliest site of nodal metastasis. This may lead to false negative results in some sentinel node biopsies