title: OSNA-based novel molecular testing for lymph node metastases in colorectal cancer patients: results from a multicenter clinical performance study in Japan.
abstract: BACKGROUND
  Lymph node (LN) metastasis in colorectal cancer (CRC) is a critical factor in making accurate prognoses and therapeutic decisions. This study evaluated the clinical performance of the one-step nucleic acid amplification (OSNA) assay in accurately diagnosing LN metastases in CRC patients through the specific detection of cytokeratin 19 mRNA levels in LNs.
  
  
  METHODS
  The OSNA assay was performed on 121 LNs dissected from early-stage CRC patients (pStage 0 or I) or from patients with benign colorectal disease (study 1). Separately, 385 LNs were dissected from 85 CRC patients (any stage); the OSNA assay was performed on half of each LN, and the results were compared with histopathological examination in 2-mm intervals of the other LN half (study 2).
  
  
  RESULTS
  In study 1, all 121 histopathologically negative LNs were also negative by the OSNA assay (concordance rate for metastasis negative: 1.0, 95% confidence interval [95% CI]: 0.976-1.0). In study 2, the concordance rate between the OSNA assay and the 2-mm-interval histopathological examination was 0.971 (95% CI: 0.950-0.984), with a sensitivity of 0.952 (95% CI: 0.881-0.987) and a specificity of 0.977 (95% CI: 0.953-0.991).
  
  
  CONCLUSIONS
  The OSNA assay provided a judgment performance equivalent to a 2-mm-interval histopathological examination, a more detailed assay than the common pathological examination. Therefore, the OSNA assay is considered a new molecular examination method for the diagnosis of LN metastases in CRC patients in clinical settings.
authors.affiliation: Department of Surgery, Osaka University, Osaka, Japan. hyamamoto@gesurg.med.osaka-u.ac.jp
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Mitsugu
authors.initials: M
authors.lastname: Sekimoto
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Oya
authors.forename: Noriko
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Fumio
authors.initials: F
authors.lastname: Konishi
authors.forename: Junichi
authors.initials: J
authors.lastname: Sasaki
authors.forename: Shigeki
authors.initials: S
authors.lastname: Yamada
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Taniyama
authors.forename: Harumi
authors.initials: H
authors.lastname: Tominaga
authors.forename: Masahiko
authors.initials: M
authors.lastname: Tsujimoto
authors.forename: Hiroki
authors.initials: H
authors.lastname: Akamatsu
authors.forename: Akio
authors.initials: A
authors.lastname: Yanagisawa
authors.forename: Chouhei
authors.initials: C
authors.lastname: Sakakura
authors.forename: Yo
authors.initials: Y
authors.lastname: Kato
authors.forename: Nariaki
authors.initials: N
authors.lastname: Matsuura
mesh_terms: D000230:Adenocarcinoma / Q000556:secondary*; D002288:Adenocarcinoma, Mucinous / Q000556:secondary*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics*; D018196:Carcinoma, Adenosquamous / Q000556:secondary*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007564:Japan; D053539:Keratin-19 / Q000235:genetics*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D021141:Nucleic Acid Amplification Techniques; D011379:Prognosis; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D053539:Keratin-19