Breast cancer surgery is commonly carried out using the sentinel node technique. In this technique, the first node in the lymphatic duct (called “sentinel node”) is identified with a dye and radioactive tracer and removed by the surgeon.

The specimen is sent to a pathologist, who makes a rapid intraoperative diagnosis using frozen sections. If the sentinel node is free of carcinoma metastasis, the surgeon does not remove the upper axillary lymph nodes. If metastasis is found, the surgeon performs complete axillary dissection. Basic information about sentinel lymph node biopsy and frozen section can be found in these links: link1, link2.


Intraoperative histopathologic examination of sentinel lymph nodes is diagnostically challenging. With standard stains (hematoxylin & eosin or toluidine blue) it is often difficult to diagnose small carcinoma metastases with certainty. Small metastases of lobular carcinoma are particularly difficult to identify.

Intraoperative cytokeratin immunostaining on frozen sections has been evaluated in several research articles.