title: Prediction of 30-day morbidity after primary cytoreductive surgery for advanced stage ovarian cancer.
abstract: OBJECTIVE
  Treatment in advanced stage epithelial ovarian cancer (EOC) is based on primary cytoreductive surgery followed by platinum-based chemotherapy. Successful cytoreduction to minimal residual tumour burden is the most important determinant of prognosis. However, extensive surgical procedures to achieve maximal debulking are inevitably associated with postoperative morbidity and mortality. The objective of this study is to determine predictors of 30-day morbidity after primary cytoreductive surgery for advanced stage EOC.
  
  
  METHODS
  All patients in the South Western part of the Netherlands who underwent primary cytoreductive surgery for advanced stage EOC between January 2004 and December 2007 were identified from the Rotterdam Cancer Registry database. All peri- and postoperative complications within 30 days after surgery were registered and classified according to the definitions of the National Surgical Quality Improvement Programme (NSQIP). To investigate independent predictors of 30-day morbidity, a Cox proportional hazards model with backward stepwise elimination was utilised. The identified predictors were entered into a nomogram.
  
  
  RESULTS
  Two hundred and ninety-three patients entered the study protocol. Optimal cytoreduction was achieved in 136 (46%) patients. 30-day morbidity was seen in 99 (34%) patients. Postoperative morbidity could be predicted by age (P=0.007; odds ratio [OR] 1.034), WHO performance status (P=0.046; OR 1.757), extent of surgery (P=0.1308; OR=2.101), and operative time (P=0.017; OR 1.007) with an optimism corrected c-statistic of 0.68.
  
  
  CONCLUSIONS
  30-day morbidity could be predicted by age, WHO performance status, operative time and extent of surgery. The generated nomogram could be valuable for predicting operative risk in the individual patient.
authors.affiliation: Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Daniel Den Hoed/Erasmus MC University Medical Center, Rotterdam, The Netherlands. c.gerestein@erasmusmc.nl
authors.forename: C G
authors.initials: CG
authors.lastname: Gerestein
authors.forename: G M
authors.initials: GM
authors.lastname: Nieuwenhuyzen-de Boer
authors.forename: M J
authors.initials: MJ
authors.lastname: Eijkemans
authors.forename: G S
authors.initials: GS
authors.lastname: Kooi
authors.forename: C W
authors.initials: CW
authors.lastname: Burger
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D008875:Middle Aged; D009367:Neoplasm Staging; D018365:Neoplasm, Residual; D049451:Nomograms; D010051:Ovarian Neoplasms / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications; D011379:Prognosis; D012042:Registries; D012307:Risk Factors; D016896:Treatment Outcome; D055815:Young Adult