title: One-Step Nucleic Acid Amplification Assay for Detection of Axillary Lymph Node Metastases in Breast Cancer Patients Treated with Neoadjuvant Chemotherapy.
abstract: BACKGROUND
  The accuracy of one-step nucleic acid amplification (OSNA) for the detection of lymph node (LN) metastasis in breast cancer patients has been well established. This study aimed to evaluate its accuracy for patients treated with neoadjuvant chemotherapy (NAC).
  
  
  METHODS
  For this study, 300 LNs, 115 sentinel lymph nodes (SLNs), and 185 non-SLNs from 88 breast cancer patients treated with NAC were examined by means of histology (hematoxylin and eosin staining and pancytokeratin immunostaining) and OSNA.
  
  
  RESULTS
  The diagnostic accuracy, sensitivity, and specificity of OSNA were respectively 92.3, 88.5, and 93.3 % for all LNs, and the corresponding values were 87.8, 75.0, and 91.2 % for SLNs and 95.1, 97.3, and 94.6 % for non-SLNs. The diagnostic accuracy of OSNA was significantly lower for SLNs than for non-SLNs (P = 0.021), which was attributable to the low sensitivity for detection of micrometastases (micromets) due to lower CK19 mRNA expression detected by in situ hybridization (ISH) in SLN micromets than in non-SLN micromets. For primary breast tumors, CK19 mRNA expression showed a significant reduction after NAC (P = 0.040).
  
  
  CONCLUSIONS
  The diagnostic accuracy of OSNA for NAC-treated patients is similar to that for NAC-nontreated patients, but its accuracy is significantly lower for SLNs than for non-SLNs. The findings obtained with CK19 mRNA ISH suggest that most SLN micromets cannot be detected by OSNA due to the reduced expression of CK19 mRNA induced by NAC.
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Takamoto
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan. kshimazu@onsurg.med.osaka-u.ac.jp.
authors.forename: Kenzo
authors.initials: K
authors.lastname: Shimazu
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yasuto
authors.initials: Y
authors.lastname: Naoi
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shimomura
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Shimoda
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Kagara
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Seung Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tamaki
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Shinzaburo
authors.initials: S
authors.lastname: Noguchi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001365:Axilla; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy / Q000235:genetics / Q000556:secondary*; D018275:Carcinoma, Lobular / Q000188:drug therapy / Q000235:genetics / Q000556:secondary*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D053539:Keratin-19 / Q000235:genetics / Q000378:metabolism; D008198:Lymph Nodes / Q000187:drug effects / Q000473:pathology*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D053539:Keratin-19; D012333:RNA, Messenger