title: Intraoperative Margin Management in Breast-Conserving Surgery: A Systematic Review of the Literature.
abstract: BACKGROUND
  Breast surgeons have a wide variety of intraoperative techniques available to help achieve low rates for positive margins of excision, with variable levels of evidence.
  
  
  METHODS
  A systematic review of the medical literature from 1995 to July 2016 was conducted, with 434 abstracts identified and evaluated. The analysis included 106 papers focused on intraoperative management of breast cancer margins and contained actionable data.
  
  
  RESULTS
  Ultrasound-guided lumpectomy for palpable tumors, as an alternative to palpation guidance, can lower positive margin rates, but the effect when used as an alternative to wire localization (WL) for nonpalpable tumors is less certain. Localization techniques such as radioactive seed localization and radioguided occult lesion localization were found potentially to lower positive margin rates as alternatives to WL depending on baseline positive margin rates. Intraoperative pathologic methods including gross histology, frozen section analysis, and imprint cytology all have the potential to lower the rates of positive margins. Cavity-shave margins and the Marginprobe device both lower rates of positive margins, with some potential for negative cosmetic effects. Specimen radiography and multiple miscellaneous techniques did not affect positive margin rates or provided too little evidence for formation of a conclusion.
  
  
  CONCLUSIONS
  A systematic review of the literature showed evidence that several intraoperative techniques and actions can lower the rates of positive margins. These results are presented together with graded recommendations.
authors.affiliation: Department of Surgery, Mayo Clinic, Phoenix, AZ, USA. gray.richard@mayo.edu.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Gray
authors.affiliation: Department of Surgery, Mayo Clinic, Phoenix, AZ, USA.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Pockaj
authors.affiliation: Department of Surgery, Mayo Clinic, Phoenix, AZ, USA.
authors.forename: Erin
authors.initials: E
authors.lastname: Garvey
authors.affiliation: UCSD Department of Surgery, UCSD Cancer Center, Encinitas, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Blair
mesh_terms: D001943:Breast Neoplasms / Q000601:surgery*; D005260:Female; D005629:Frozen Sections; D006801:Humans; D007432:Intraoperative Period; D000072662:Margins of Excision; D015412:Mastectomy, Segmental / Q000379:methods*; D010173:Palpation; D011846:Radio Waves; D012086:Reoperation; D013057:Spectrum Analysis; D018084:Ultrasonography, Interventional