title: A prospective, blinded trial of touch prep analysis versus frozen section for intraoperative evaluation of sentinel lymph nodes in breast cancer.
abstract: BACKGROUND
  Sentinel lymph node biopsy (SLNB) has largely replaced axillary dissection (ALND) for axillary staging in early breast cancer. However, intense pathologic evaluation is not routinely available intraoperatively; therefore, patients with SLN metastasis may require a second surgery for completion ALND. We hypothesized that a single-section approach (by either frozen section [FS] or touch preparation analysis [TPA]) could be accurate for intraoperative SLN evaluation.
  
  
  METHODS
  We performed a prospective, blinded study of patients undergoing SLNB for breast cancer from September 2004 to July 2006. SLNs were bivalved along the long axis, underwent FS and TPA of the facing halves, followed by routine sentinel node processing (serial sectioning with hematoxylin/eosin staining). A single pathologist reviewed all study slides and was blinded to the permanent section interpretation.
  
  
  RESULTS
  We analyzed 233 nodes from 118 patients. Overall, 21% of patients (N = 25) had SLN metastasis by serial-section histopathology. Single-section FS and TPA had similar sensitivities (0.67 and 0.66, P = .82) and specificities (0.995 and 0.995, P = 1.0) for detection of SLN metastasis, yielding equivalent accuracies (95%). All micrometastases (<2 mm; N = 4) were missed by both techniques. False positives were rare-only one in each group (2% overall).
  
  
  CONCLUSIONS
  Single-section TPA and FS have similar accuracies and can be safely used to identify the majority of patients with SLN metastasis, sparing these patients a delayed ALND. False-negative results from TPA or FS occur in patients with micrometastatic disease, for which the role of completion ALND remains controversial.
authors.affiliation: Department of Surgery, University of California Davis Medical Center, Sacramento, CA, 95817, USA.
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Vanderveen
authors.forename: Rajendra
authors.initials: R
authors.lastname: Ramsamooj
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Bold
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology*; D003581:Cytodiagnosis; D005260:Female; D005629:Frozen Sections; D006801:Humans; D007432:Intraoperative Period; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009367:Neoplasm Staging; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy; D016037:Single-Blind Method