title: Utility of intraoperative frozen section examinations of surgical margins: implication of margin-exposed tumor component features on further surgical treatment.
abstract: OBJECTIVE
  In patients who underwent breast-conserving surgery, we attempted to identify the histological characteristics of margin-exposed tumor components on intraoperative frozen section examinations that were predictive of residual tumor components in additionally resected specimens.
  
  
  METHODS
  Of 1835 patients who underwent breast-conserving surgery, we identified 220 patients who had positive surgical margins determined by intraoperative frozen section examinations and who had undergone immediate additional resections. Two observers (M.K., H.T.) reviewed the slides of frozen sections and confirmed the presence of tumor components.
  
  
  RESULTS
  In additionally resected specimens, residual tumors were detected in 115 cases (52.3%) but not in 105 cases (47.7%). The primary tumor characteristics of extensive intraductal component (+), younger age, invasive lobular carcinoma and pathological T3 classification were significantly associated with the residual tumor components. The margin-exposed tumor components of the maximum diameter, number of positive margins and histological type were correlated with the residual tumors. Multivariate analysis showed that the maximum tumor diameter was an independent risk factor for residual tumors.
  
  
  CONCLUSIONS
  Diagnosis of positive margins by intraoperative frozen section examinations was useful for predicting residual tumors, and three histological properties of the margin-exposed tumor components were correlated with the status of residual tumor components. Although it was impossible to clearly identify the single main factor for predicting patients for whom additional resections were not necessary, it may be possible to consider stratification of additional surgical therapy according to the characteristics of margin-exposed tumor components on intraoperative frozen section examinations.
authors.affiliation: Department of Metabolic Care and Endocrine Surgery, Graduate School of Medicine, University of Tokyo, Tokyo Department of Breast Surgery, National Cancer Center Hospital, Tokyo Department of Breast Surgery, Kanto Central Hospital of the Mutual Aid Association of Public School Teachers, Tokyo.
authors.forename: Mizuho
authors.initials: M
authors.lastname: Kikuyama
authors.affiliation: Department of Breast Surgery, National Cancer Center Hospital, Tokyo Breast Surgical Oncology Department, Showa University, School of Medicine, Tokyo.
authors.forename: Sadako
authors.initials: S
authors.lastname: Akashi-Tanaka
authors.affiliation: Department of Breast Surgery, National Cancer Center Hospital, Tokyo.
authors.forename: Takashi
authors.initials: T
authors.lastname: Hojo
authors.affiliation: Department of Breast Surgery, National Cancer Center Hospital, Tokyo.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kinoshita
authors.affiliation: Department of Metabolic Care and Endocrine Surgery, Graduate School of Medicine, University of Tokyo, Tokyo Department of Breast Surgery, Dokkyo Medical University, Saitama.
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Ogawa
authors.affiliation: Department of Metabolic Care and Endocrine Surgery, Graduate School of Medicine, University of Tokyo, Tokyo.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Seto
authors.affiliation: Department of Pathology and Clinical Laboratories, National Cancer Center Hospital, Tokyo Department of Basic Pathology, National Defense Medical College, Saitama, Japan hstsuda@gmail.com.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tsuda
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery*; D018275:Carcinoma, Lobular / Q000601:surgery; D005260:Female; D005629:Frozen Sections; D006801:Humans; D007432:Intraoperative Period; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009367:Neoplasm Staging; D018365:Neoplasm, Residual / Q000175:diagnosis*; D059351:Organ Sparing Treatments; D011237:Predictive Value of Tests; D012307:Risk Factors
keywords: breast cancer; breast-conserving surgery; residual tumor