title: Intraoperative diagnosis of sentinel lymph node metastases in breast cancer treatment with one-step nucleic acid amplification assay (OSNA).
abstract: BACKGROUND
  The aim of the study was to evaluate the clinical usefulness of a one-step nucleic acid amplification assay (OSNA) for intraoperative detection of metastases to sentinel lymph nodes (SLNs) in comparison to examination of frozen sections, and to summarize the results of previous studies.
  
  
  METHODS
  We enrolled 98 patients aged 58.13 ±10.74 years treated surgically for breast cancer, and 99 biopsies of SLNs were followed by analysis of 105 SLNs. The central 1 mm slice of SLN was used for examination of frozen sections, whereas 2 outer slices of SLNs were analyzed intraoperatively with OSNA. Detection of isolated tumor cells (ITC), micrometastases or macrometastases with OSNA extended surgery to axillary lymph node dissection. Congruency of results was assessed between OSNA and examination of frozen sections.
  
  
  RESULTS
  One-step nucleic acid amplification assay detected metastases in 29/105 SLNs in surgery of 27/99 breasts, including ITC in 3/29 SLNs, micrometastases in 12/29 and macrometastases in 14/29. One-step nucleic acid amplification assay detected significantly more metastases to SLNs than examination of frozen sections (p< 0.0001). All 8 inconsistent results were positive in OSNA and negative in examination of frozen sections; ITC were identified in 2/8 SLNs and micrometastases in 6/8 SLNs. Sensitivity for OSNA was calculated as 100%, specificity as 90.47%, and κ was 79.16%.
  
  
  CONCLUSIONS
  One-step nucleic acid amplification assay analysis allows rapid and quantitative detection of mRNA CK19 with high specificity and a low rate of false positives. One-step nucleic acid amplification assay is a reliable tool for intraoperative diagnosis of whole SLNs during surgery of breast cancer. One-step nucleic acid amplification assay minimizes the need for secondary surgery and avoids delays in the adjuvant treatment.
authors.affiliation: Department of Oncological Surgery and Breast Diseases, Institute of Polish Mother's Memorial Hospital, Lodz, Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Szychta
authors.affiliation: Department of Oncological Surgery and Breast Diseases, Institute of Polish Mother's Memorial Hospital, Lodz, Poland.
authors.forename: Bogusław
authors.initials: B
authors.lastname: Westfal
authors.affiliation: Department of Oncological Surgery and Breast Diseases, Institute of Polish Mother's Memorial Hospital, Lodz, Poland.
authors.forename: Rafał
authors.initials: R
authors.lastname: Maciejczyk
authors.affiliation: Laboratory of Molecular Genetics, Department of Pathology, Institute of Polish Mother's Memorial Hospital, Lodz, Poland.
authors.forename: Beata
authors.initials: B
authors.lastname: Smolarz
authors.affiliation: Laboratory of Molecular Genetics, Department of Pathology, Institute of Polish Mother's Memorial Hospital, Lodz, Poland.
authors.forename: Hanna
authors.initials: H
authors.lastname: Romanowicz
authors.affiliation: Laboratory of Molecular Genetics, Department of Pathology, Institute of Polish Mother's Memorial Hospital, Lodz, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Krawczyk
authors.affiliation: Department of Oncological Surgery and Breast Diseases, Institute of Polish Mother's Memorial Hospital, Lodz, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Zadrożny
keywords: breast cancer; cytokeratin 19; intraoperative molecular study; sentinel lymph node