title: The diagnostic utility of preoperative breast magnetic resonance imaging (MRI) and/or intraoperative sub-nipple biopsy in nipple-sparing mastectomy.
abstract: BACKGROUND
  The necessity of routine sub-nipple biopsy was uncertain, and the role of preoperative magnetic resonance imaging (MRI) in detecting nipple invasion in patients who have been selected for nipple sparing mastectomy (NSM) has not been adequately evaluated.
  
  
  METHODS
  We retrospectively collected and analyzed the medical and surgical records of 434 patients with primary operable breast cancer who met the criteria for NSM and underwent breast surgery during the period January 2011 to December 2015. Patients were stratified into three risk groups (low, intermediate, and high) according to tumor size and tumor-to-nipple distance.
  
  
  RESULTS
  Among the 434 patients in this study, 29 (6.7%) had occult invasion of the nipple-areola complex (NAC). Sub-nipple biopsy had a sensitivity of 84.6%, a specificity of 100%, a false negative rate of 1.2%, a false positive rate of 0%, and an overall accuracy rate of 98.8% in confirming NAC invasion. The NAC invasion rate was 0% in the low-risk group, 5.1% in the intermediate-risk group, and 19.7% in the high-risk group (P < 0.01). The overall NPV of preoperative MRI for predicting NAC invasion was 94.8%. Cost analysis revealed that the cost of NSM with sub-nipple biopsy was significantly higher than that of NSM alone, with a mean difference in cost of USD 238.5 (P < 0.01).
  
  
  CONCLUSIONS
  The high negative predictive value of MRI for NAC invasion is useful for selection of patients receiving NSM. Sub-nipple biopsy is a reliable procedure to detect occult NAC invasion, however, routine use is not cost-effect for low risk patients.
authors: Department of Surgical Medicine, Erlin Branch of Changhua Christian Hospital, Changhua, Taiwan; Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan; Division of General Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan.
authors: S-E
authors: SE
authors: Chan
authors: Department of Radiology, Changhua Christian Hospital, Changhua, Taiwan.
authors: C-Y
authors: CY
authors: Liao
authors: Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan; Division of General Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan; Division of general surgery, Saint Paul's Hospital, Taoyuan, Taiwan.
authors: T-Y
authors: TY
authors: Wang
authors: Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan; Division of General Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan.
authors: S-T
authors: ST
authors: Chen
authors: Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan; Division of General Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan.
authors: D-R
authors: DR
authors: Chen
authors: Tumor Center, Changhua Christian Hospital, Changhua, Taiwan.
authors: Y-J
authors: YJ
authors: Lin
authors: Department of Surgical Pathology, Changhua Christian Hospital, Changhua, Taiwan; School of Medicine, Chung Shan Medical University, Taichung, Taiwan; Department of Medical Technology, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli, Taiwan.
authors: C-J
authors: CJ
authors: Chen
authors: Department of Radiology, Changhua Christian Hospital, Changhua, Taiwan.
authors: H-K
authors: HK
authors: Wu
authors: Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan.
authors: S-L
authors: SL
authors: Chen
authors: Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan; Division of General Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan.
authors: S-J
authors: SJ
authors: Kuo
authors: Department of Radiology, Changhua Christian Hospital, Changhua, Taiwan.
authors: C-W
authors: CW
authors: Lee
authors: Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan; Division of General Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan; School of Medicine, National Yang Ming University, Taipei, Taiwan. Electronic address: 143809@cch.org.tw.
authors: H-W
authors: HW
authors: Lai
mesh_terms: D001706:Biopsy; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008408:Mastectomy / Q000379:methods*; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000000981:diagnostic imaging / Q000473:pathology; D009558:Nipples; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity
keywords: Cost-effectiveness analysis; Magnetic resonance imaging; Nipple sparing mastectomy; Sub-nipple biopsy