title: Frozen section during partial nephrectomy: does it predict positive margins?
abstract: OBJECTIVE
  To investigate the clinical utility of frozen section (FS) analysis performed during partial nephrectomy (PN) and its influence on intra-operative management.
  
  
  METHODS
  We performed a retrospective analysis of consecutive PN cases from 2010 to 2013. We evaluated the concordance between the intra-operative FS diagnosis and the FS control diagnosis, a postoperative quality assurance measure performed on all FS diagnoses after formalin fixation of the tissue. We also evaluated the concordance between the intra-operative FS diagnosis and the final specimen margin. Operating reports were reviewed for change in intra-operative management for cases with a positive or atypia FS diagnosis, or if the mass was sent for FS.
  
  
  RESULTS
  A total of 576 intra-operative FSs were performed in 351 cases to assess the PN tumour bed margin, 19 (5.4%) of which also had a mass sent for FS to assess the tumour type. The concordance rate between the FS diagnosis and the FS control diagnosis was 98.3%. There were 30 (8.5%) final positive specimen margins, of which four (13.3%) were classified as atypia, 17 (56.7%) as negative and nine (30%) as positive on FS diagnosis. Intra-operative management was influenced in six of nine cases with a positive FS diagnosis and in one of nine cases with an FS diagnosis of atypia.
  
  
  CONCLUSIONS
  The relatively high false-negative rate, controversy over the prognosis of a positive margin, and inconsistency in influencing intra-operative management are arguments against the routine use of FS in PN cases.
authors.affiliation: Departments of Pathology and Urology, The University of Alabama, Birmingham, AL, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Gordetsky
authors.affiliation: Department of Urology, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Gorin
authors.affiliation: Department of Surgery, Center for Surgical Trials and Outcomes Research, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Joe
authors.initials: J
authors.lastname: Canner
authors.affiliation: Department of Urology, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Ball
authors.affiliation: Department of Urology, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Phillip M
authors.initials: PM
authors.lastname: Pierorazio
authors.affiliation: Department of Urology, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Mohamad E
authors.initials: ME
authors.lastname: Allaf
authors.affiliation: Department of Urology, The Johns Hopkins Hospital, Baltimore, MD, USA.|Department of Pathology, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Jonathan I
authors.initials: JI
authors.lastname: Epstein
mesh_terms: D000368:Aged; D005260:Female; D005629:Frozen Sections / Q000706:statistics & numerical data*; D006801:Humans; D007680:Kidney Neoplasms / Q000453:epidemiology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000706:statistics & numerical data*; D012189:Retrospective Studies
keywords: frozen section; margins; partial nephrectomy