title: Intra-operative rapid diagnostic method based on CK19 mRNA expression for the detection of lymph node metastases in breast cancer.
abstract: Staging by sentinel node (SN) biopsy is the standard procedure for clinically node-negative breast cancer patients. Intra-operative analysis of the SN allows immediate axillary lymph node (ALN) dissection in SN positive patients, but a quick, reliable and reproducible method is lacking. We tested the suitability of a quantitative cytokeratin 19 (CK19) mRNA one step nucleic acid amplification (OSNA#) technique (OSNA-CK19) for intra-operative SN analysis. OSNA-CK19 involves a short manual sample preparation step and subsequent fully automated amplification of CK19 mRNA based on reverse transcription loop-mediated isothermal amplification, with results available within 30-40 min. OSNA-CK19 was compared to histological staining (Hematoxylin&Eosin and CAM5.2 and CK19 immunostaining) of 346 frozen ALNs from 32 breast cancer patients, using half of the lymph node for each method. 267 samples were negative and 61 positive by both methods. Three samples were histology positive and OSNA-CK19 negative. Fifteen samples were histology negative and OSNA-CK19 positive, 11 of which had copy numbers close to the cut-off level of OSNA-CK19. Seven of these 15 samples were RT-PCR positive for epithelial markers and/or showed CK19 protein expression by Western blot suggesting the presence of tumor deposits in the lymph node part investigated by OSNA-CK19. Concordance with histology was 94.8%, and 96.8% after exclusion of the latter 7 discordant cases. Sensitivity was 95.3% and specificity was 94.7% before and 97.1% after discordant case investigation. Our results indicate that OSNA-CK19 can potentially be useful in an intra-operative clinical setting to detect SN tumor involvement in breast cancer patients.
authors.affiliation: Department of Pathology, VU Medical Center Amsterdam, The Netherlands.
authors.forename: Mike
authors.initials: M
authors.lastname: Visser
authors.forename: Mehdi
authors.initials: M
authors.lastname: Jiwa
authors.forename: Anja
authors.initials: A
authors.lastname: Horstman
authors.forename: Antoinette A T P
authors.initials: AA
authors.lastname: Brink
authors.forename: Rene P
authors.initials: RP
authors.lastname: Pol
authors.forename: Paul
authors.initials: P
authors.lastname: van Diest
authors.forename: Peter J F
authors.initials: PJ
authors.lastname: Snijders
authors.forename: Chris J L M
authors.initials: CJ
authors.lastname: Meijer
mesh_terms: D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000235:genetics; D001365:Axilla; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000737:chemistry* / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D005629:Frozen Sections; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007432:Intraoperative Period; D053539:Keratin-19 / Q000032:analysis* / Q000235:genetics; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000737:chemistry* / Q000473:pathology / Q000601:surgery; D008207:Lymphatic Metastasis / Q000175:diagnosis; D008875:Middle Aged; D009367:Neoplasm Staging; D021141:Nucleic Acid Amplification Techniques; D011237:Predictive Value of Tests; D012313:RNA; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D053539:Keratin-19; C034477:RNA primers; D012333:RNA, Messenger; C050269:organ-specific neoantigen; D012313:RNA