%0 Journal Article %T Cytokeratin on Frozen Sections of Sentinel Node May Spare Breast Cancer Patients Secondary Axillary Surgery %A Elisabeth Specht Stovgaard %A Tove Filtenborg Tvedskov %A Anne Vibeke L£¿nkholm %A Eva Balslev %J Pathology Research International %D 2012 %I Hindawi Publishing Corporation %R 10.1155/2012/802184 %X Background. The feasibility and accuracy of immunohistochemistry (IHC) on frozen sections, when assessing sentinel node (SN) status intraoperatively in breast cancer, is a matter of continuing discussion. In this study, we compared a center using IHC on frozen section with a center not using this method with focus on intraoperative diagnostic values. Material and Methods. Results from 336 patients from the centre using IHC intraoperatively were compared with 343 patients from the center not using IHC on frozen section. Final evaluation on paraffin sections with haematoxylin-eosin (HE) staining supplemented with cytokeratin staining was used as gold standard. Results. Significantly more SN with isolated tumor cells (ITCs) and micrometastases (MICs) were found intraoperatively when using IHC on frozen sections. There was no significant difference in the number of macrometastases (MACs) found intraoperatively. IHC increased the sensitivity, the negative predictive value, and the accuracy of the intraoperative evaluation of SN without decreasing the specificity and positive predictive value of SN evaluation. Conclusions. IHC on frozen section leads to the detection of more ITC and MIC intraoperatively. As axillary lymph node dissection (ALND) is performed routinely in some countries when ITC and MIC are found in the SN, IHC on frozen section provides valuable information that can lead to fewer secondary ALNDs. 1. Introduction Axillary lymph node status is the most important prognostic factor in breast cancer. Sentinel node biopsy (SNB) is regarded as an accurate method for assessing axillary lymph node status in patients with early breast cancer [1, 2]. The more comprehensive analysis of SNs has resulted in increased detection of metastatic and micrometastatic disease both by haematoxylin-eosin (HE) staining and by immunohistochemistry (IHC) [3¨C5]. Only in case of involvement of the SN are patients offered an axillary lymph node dissection (ALND). If SN involvement is found intraoperatively, ALND can be done immediately at the same operation and patients are spared a two-stage procedure. However, there is no universal agreement on the optimal method for the intraoperative examination of the SNs. A higher number of SN involvement diagnosed correctly intraoperatively would increase the number of patients having ALND in the same operation and fewer would go through a second axillary operation because of late diagnosis of SN involvement. In 2003, the American Joint Committee on Cancer (AJCC) revised the breast cancer staging system (6th edition) with particular %U http://www.hindawi.com/journals/pri/2012/802184/