Intraoperative examination of sentinel lymph nodes by immunohistochemical staining in patients with breast cancer

Aim To performed a prospective investigation of the relative merits of rapid cytokeratin immunohistochemical (CK-IHC) staining of the SLN removed during the operation of breast cancer patients. Study design Between December 2002 and March 2004, 62 patients with T1 and T2 breast cancer were enrolled after undergoing successful sentinel lymph node biopsy. Eighty-nine sentinel lymph nodes (mean number, 1.44) were biopsied and first examined by hematoxylin–eosin (H&E) stained frozen section. All the tumour free sentinel lymph nodes by H&E stained frozen section were immunostained for cytokeratin using a rapid immunohistochemical assay (Cytokeratin (PAN), 1:50, Novocastra Lab., Newcastle, UK) during the operations. Results Rapid IHC staining revealed seven positive sentinel lymph nodes that were negative for metastasis by H&E staining. This study showed a sensitivity of 92.86%, a specificity of 100%, an accuracy of 98.9%, and a negative predictive value of 98.7%. Conclusions The intraoperative examination of sentinel lymph nodes is an accurate and effective way of predicting the axillary lymph node status of patients with breast cancers.