title: Large variation between hospitals in immediate breast reconstruction rates after mastectomy for breast cancer in the Netherlands.
abstract: BACKGROUND
  The present study aimed to describe the use of immediate breast reconstruction (IBR) after mastectomy for invasive breast cancer and ductal carcinoma in situ (DCIS) in hospitals in the Netherlands and determine whether patient and tumor factors account for the variation.
  
  
  METHODS
  Patients undergoing mastectomy for primary invasive breast cancer or DCIS diagnosed between January 1, 2011 and December 31, 2013 were selected from the NABON Breast Cancer Audit. All the 92 hospitals in the Netherlands were included. The use of IBR in all hospitals was compared using unadjusted and adjusted analyses. Patient and tumor factors were evaluated by univariate and multivariate analyses.
  
  
  RESULTS
  In total, 16,953 patients underwent mastectomy: 15,072 for invasive breast cancer and 1881 for DCIS. Unadjusted analyses revealed considerable variation between hospitals in postmastectomy IBR rates for invasive breast cancer (mean 17%; range 0-64%) and DCIS (mean 42%; range 0-83%). For DCIS, younger age and multifocal disease were factors that significantly increased IBR rates. For patients diagnosed with invasive breast cancer, IBR was more often used in younger patients, multifocal tumors, smaller tumors, tumors with a lower grade, absence of lymph node involvement, ductal carcinomas, or hormone-receptor positive/HER2-positive tumors. After case-mix adjustments for these factors, the variation in the use of IBR between hospitals remained large (0-43% for invasive breast cancer and 0-74% for DCIS).
  
  
  CONCLUSIONS
  A large variation between hospitals was found in postmastectomy IBR rates in the Netherlands for both invasive breast cancer and DCIS even after adjustment for patient and tumor factors.
authors.affiliation: Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: A C M
authors.initials: AC
authors.lastname: van Bommel
authors.affiliation: Department of Plastic and Reconstructive Surgery, Erasmus MC Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: M A M
authors.initials: MA
authors.lastname: Mureau
authors.affiliation: Department of Research, Netherlands Comprehensive Cancer Organization (IKNL), Utrecht, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Schreuder
authors.affiliation: Department of Surgery, Diakonessenhuis Utrecht, Utrecht, The Netherlands.
authors.forename: T
authors.initials: T
authors.lastname: van Dalen
authors.affiliation: Department of Surgery, Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: M T F D
authors.initials: MT
authors.lastname: Vrancken Peeters
authors.affiliation: Dutch Breast Cancer Association, Utrecht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Schrieks
authors.affiliation: Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: J H
authors.initials: JH
authors.lastname: Maduro
authors.affiliation: Department of Research, Netherlands Comprehensive Cancer Organization (IKNL), Utrecht, The Netherlands; Department of Health Technology and Services Research, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands. Electronic address: s.siesling@iknl.nl.
authors.forename: S
authors.initials: S
authors.lastname: Siesling
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D016462:Mammaplasty / Q000379:methods*; D008408:Mastectomy; D008875:Middle Aged; D009426:Netherlands; D012042:Registries; D012189:Retrospective Studies
keywords: Breast cancer; Case-mix; Hospital variation; Immediate breast reconstruction; Mastectomy