PT  - JOURNAL ARTICLE
AU  - Cristina Deambrogio
AU  - Isabella Castellano
AU  - Alessia Paganotti
AU  - Elisabetta Omodeo Zorini
AU  - Fabio Corsi
AU  - Riccardo Bussone
AU  - Roberto Franchini
AU  - Jlenia Antona
AU  - Umberto Miglio
AU  - Anna Sapino
AU  - Concetta Antonacci
AU  - Renzo Boldorini
TI  - A new clinical cut-off of cytokeratin 19 mRNA copy number in sentinel lymph node better identifies patients eligible for axillary lymph node dissection in breast cancer
AID  - 10.1136/jclinpath-2014-202384
DP  - 2014 Aug 01
TA  - Journal of Clinical Pathology
PG  - 702--706
VI  - 67
IP  - 8
4099  - http://jcp.bmj.com/content/67/8/702.short
4100  - http://jcp.bmj.com/content/67/8/702.full
SO  - J Clin Pathol2014 Aug 01; 67
AB  - Aims Cytokeratin 19 (CK19) mRNA copy number predicts the probability of tumour load in axillary lymph nodes (ALN) and can help in decision-making regarding the axillary dissection. The purpose of this study was to define a new cut-off of CK19 mRNA copy number using the one-step nucleic acid amplification (OSNA) assay on metastatic sentinel lymph nodes (SLN) in order to identify cases at risk of having one or more positive ALN. Methods 1296 SLN from 1080 patients were analysed with the OSNA assay. 194 patients with positive SLN underwent ALN dissection and the mean value of CK19 copy number (320 000) of their SLN was set as initial cut-off. Receiver operative characteristics curve identify a best cut-off of 7700 (sensitivity 78%, specificity 57%). A comparison between our and the traditional cut-off (5000) was performed. Results The cut-off of 7700 successfully identifies patients with positive ALN (p=0.001, false- negative cases: 17%). In the range between 5000 and 7700, one patient with positive ALN would not undergo axillary dissection, whereas eight patients with negative ALN would be correctly identified. Conclusions We suggest that the level of CK19 mRNA copy number could be the only parameter to consider in the intraoperative management of the axilla.