title: Routine clinical use of the one-step nucleic acid amplification assay for detection of sentinel lymph node metastases in breast cancer patients: results of a multicenter study in Japan.
abstract: BACKGROUND
  The objective of this study was to confirm, by means of a multicenter study conducted in Japan, the reliability and usefulness of the one-step nucleic acid amplification (OSNA) assay in routine clinical use for sentinel lymph node biopsy (SLNB) of breast cancer patients.
  
  
  METHODS
  Patients with Tis-T2N0M0 breast cancer who underwent SLNB before systemic chemotherapy comprised the study cohort. A whole sentinel lymph node (SLN) was examined intraoperatively with the OSNA assay except for a 1-mm-thick, central slice of the lymph node, which underwent pathologic examination after the operation. For patients who underwent axillary dissection, non-SLNs were examined with routine pathologic examination.
  
  
  RESULTS
  In total, 417 SLNBs from 413 patients were analyzed. SLN metastases were detected with greater sensitivity by the OSNA assay than by pathologic examination (22.5% vs 15.8%; P < .001), as expected from the difference in size of the specimens examined. Patients who had SLN metastases assessed with the OSNA assay proved to harbor non-SLN metastases with an overall risk ratio of 33.7%. The risk of non-SLN metastasis was significantly lower for patients who had positive SLNs assessed as OSNA+ than for those who had SLNs assessed as OSNA++ (17.6% vs 44%; P = .012).
  
  
  CONCLUSIONS
  The OSNA assay can be used for routine clinical SLNB, and its assessment for volume of metastasis may be a powerful predictive factor for non-SLN metastasis. Further studies with more patients are needed to confirm the usefulness of this assay for selection in the clinical setting of patients who do not need axillary dissection.
authors.affiliation: Department of Breast and Endocrine Surgery, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tamaki
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Sato
authors.forename: Keiichi
authors.initials: K
authors.lastname: Homma
authors.forename: Daisuke
authors.initials: D
authors.lastname: Takabatake
authors.forename: Rieko
authors.initials: R
authors.lastname: Nishimura
authors.forename: Masahiko
authors.initials: M
authors.lastname: Tsujimoto
authors.forename: Katsuhide
authors.initials: K
authors.lastname: Yoshidome
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tsuda
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kinoshita
authors.forename: Hironori
authors.initials: H
authors.lastname: Kato
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Taniyama
authors.forename: Takako
authors.initials: T
authors.lastname: Kamio
authors.forename: Seigo
authors.initials: S
authors.lastname: Nakamura
authors.forename: Futoshi
authors.initials: F
authors.lastname: Akiyama
authors.forename: Shinzaburo
authors.initials: S
authors.lastname: Noguchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D007564:Japan; D053539:Keratin-19 / Q000032:analysis / Q000235:genetics*; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D012313:RNA / Q000032:analysis; D015203:Reproducibility of Results; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*
chemical_list: D053539:Keratin-19; D012313:RNA