title: Increased postoperative complications in bilateral mastectomy patients compared to unilateral mastectomy: an analysis of the NSQIP database.
abstract: BACKGROUND
  Recent studies indicate that women with unilateral breast cancer are choosing contralateral prophylactic mastectomy (CPM) at an increasing rate. There is limited literature evaluating the postoperative complication rates associated with CPM without breast reconstruction. The objective of this study was to compare postoperative complications in women undergoing unilateral mastectomy (UM) and sentinel lymph node biopsy (SLNB) to those undergoing bilateral mastectomy (BM) and SLNB for the treatment of their breast cancer.
  
  
  METHODS
  The American College of Surgeons National Surgery Quality Improvement Program (ACS NSQIP) Participant Use Files between 2007 and 2010 were used to identify women with breast cancer undergoing UM or BM with SLNB. Individual and composite end points of 30-day complications were used to compare both groups by univariate and multivariate analyses.
  
  
  RESULTS
  We identified 4,219 breast cancer patients who had a SLNB: 3,722 (88.2 %) had UM and 497 (11.8 %) had BM. The wound complication rate was significantly higher in the BM group versus the UM group, 5.8 % versus 2.9 % [unadjusted odds ratio (OR) 2.1, 95 % confidence interval (CI) 1.3-3.3, P < 0.01]. The overall 30-day complication rate in UM patients was 4.2 % versus 7.6 % in the BM group (unadjusted OR 1.9, 95 % CI 1.3-2.7, P < 0.01). The adjusted OR for overall complications adjusting for important patient characteristics was 1.9 (95 % CI 1.3-2.8, P < 0.01). Independent predictors of overall postoperative complications were body mass index (OR 1.1, P < 0.01) and smoking (OR 2.2, P < 0.01).
  
  
  CONCLUSIONS
  For patients with breast cancer, bilateral mastectomy is associated with an increased risk of wound and overall postoperative complications. Discussion of these outcomes is imperative when counseling women contemplating CPM.
authors.affiliation: Department of Surgery, University of Toronto, Toronto, ON, Canada.
authors.forename: Fahima
authors.initials: F
authors.lastname: Osman
authors.forename: Fady
authors.initials: F
authors.lastname: Saleh
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Jackson
authors.forename: Mark A
authors.initials: MA
authors.lastname: Corrigan
authors.forename: Tulin
authors.initials: T
authors.lastname: Cil
mesh_terms: D000368:Aged; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000150:complications* / Q000601:surgery; D016208:Databases, Factual; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000209:etiology; D008408:Mastectomy / Q000009:adverse effects*; D008875:Middle Aged; D009367:Neoplasm Staging; D011183:Postoperative Complications; D011379:Prognosis; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000209:etiology; D021701:Sentinel Lymph Node Biopsy