title: Radioactive Seed Localization or Wire-guided Localization of Nonpalpable Invasive and In Situ Breast Cancer: A Randomized, Multicenter, Open-label Trial.
abstract: To compare the rate of positive resection margins between radioactive seed localization (RSL) and wire-guided localization (WGL) after breast conserving surgery (BCS).
  
  
  
  WGL is the current standard for localization of nonpalpable breast lesions in BCS, but there are several difficulties related to the method.
  
  
  
  From January 1, 2014 to February 4, 2016, patients with nonpalpable invasive breast cancer or DCIS visible on ultrasound were enrolled in this randomized, multicenter, open-label clinical trial, and randomly assigned to RSL or WGL. The primary outcome was margin status after BCS. Secondary outcomes were duration of the surgical procedure, weight of surgical specimen, and patients' pain perception. Analyses were performed by intention-to-treat (ITT) and per protocol.
  
  
  
  Out of 444 eligible patients, 413 lesions representing 409 patients were randomized; 207 to RSL and 206 to WGL. Twenty-three did not meet inclusion criteria, chose to withdraw, or had a change in surgical management and were excluded. The remaining 390 lesions constituted the ITT population. Here, resection margins were positive in 23 cases (11.8%) in the RSL group compared with 26 cases (13.3%) in the WGL group (P = 0.65). The per-protocol analysis revealed no difference in margin status (P = 0.62). There were no significant differences in the duration of the surgical procedure (P = 0.12), weight of the surgical specimen (P = 0.54) or the patients' pain perception (P = 0.28).
  
  
  
  RSL offers a major logistic advantage, as localization can be done several days before surgery without any increase in positive resection margins compared with WGL.
authors.affiliation: *Department of Plastic Surgery, Breast Surgery and Burns, Rigshospitalet, University of Copenhagen, Denmark †Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University of Copenhagen, Denmark ‡Danish Breast Cancer Group, Rigshospitalet, University of Copenhagen, Denmark §Department of Pathology, Rigshospitalet, University of Copenhagen, Denmark ¶Department of Radiology, Rigshospitalet, University of Copenhagen, Denmark ||Department of Pathology, Herlev Hospital, University of Copenhagen, Denmark **Department of Clinical Physiology and Nuclear Medicine, Herlev Hospital, University of Copenhagen, Denmark ††Department of Breast Surgery, Herlev Hospital, University of Copenhagen, Denmark.
authors.forename: Linnea
authors.initials: L
authors.lastname: Langhans
authors.forename: Tove F
authors.initials: TF
authors.lastname: Tvedskov
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Klausen
authors.forename: Maj-Britt
authors.initials: MB
authors.lastname: Jensen
authors.forename: Maj-Lis
authors.initials: ML
authors.lastname: Talman
authors.forename: Ilse
authors.initials: I
authors.lastname: Vejborg
authors.forename: Cemil
authors.initials: C
authors.lastname: Benian
authors.forename: Anne
authors.initials: A
authors.lastname: Roslind
authors.forename: Jonas
authors.initials: J
authors.lastname: Hermansen
authors.forename: Peter S
authors.initials: PS
authors.lastname: Oturai
authors.forename: Niels
authors.initials: N
authors.lastname: Bentzon
authors.forename: Niels
authors.initials: N
authors.lastname: Kroman
mesh_terms: D000368:Aged; D000071960:Breast Carcinoma In Situ / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D000072662:Margins of Excision; D015412:Mastectomy, Segmental / Q000009:adverse effects / Q000379:methods*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009366:Neoplasm Seeding; D061646:Operative Time; D058748:Pain Perception; D010149:Postoperative Pain; D014463:Ultrasonography
chemical_list: D007457:Iodine Radioisotopes