title: Surgical management of stage T1 renal tumours at Canadian academic centres.
abstract: BACKGROUND
  The proportion of patients with stage 1 renal tumours receiving partial nephrectomy is considered a quality of care indicator. The objective of this study was to characterize surgical practice patterns at Canadian academic institutions for the treatment of these tumours.
  
  
  METHODS
  The Canadian Kidney Cancer Information System (CKCis) is a multicentre collaboration of 13 academic institutions in Canada. All patients with pathologic stage T1 renal tumours in CKCis were identified. Descriptive statistics were performed to characterize practice patterns over time. Associations between patient, tumour, and treatment factors with the use of partial nephrectomy were determined.
  
  
  RESULTS
  From 1988 to April 2014, 1453 patients with pathologic stage 1 renal tumours were entered in the CKCis database. Of these, 977 (67%) patients had pT1a tumours; of these, 765 (78%) received partial nephrectomy. Of the total number of patients (1453), 476 (33%) had pT1b tumours; of these, 204 (43%) received partial nephrectomy. The use of partial nephrectomy increased over time from 60% to 90% for pT1a tumours and 20% to 60% for pT1b tumours. Stage pT1b (relative risk [RR] 0.56, 95% confidence interval [CI] 0.50-0.63) and minimally invasive surgical approach (RR 0.78, 95% CI 0.73-0.84 for pT1a and RR 0.23, 95% CI 0.17-0.30 for pT1b) were associated with decreased use of partial nephrectomy. Most patient factors including age, gender, body mass index, hypertension, and renal function were not significantly associated with use of partial nephrectomy (p > 0.05).
  
  
  CONCLUSIONS
  Almost all pT1a and most pT1b renal tumours managed surgically at academic centres in Canada receive partial nephrectomy. The use of partial versus radical nephrectomy appears to occur independently of patient age and comorbid status, which may indicate that urologists are performing partial nephrectomy whenever technically feasible based on tumour factors. Although the ideal proportion patients receiving partial nephrectomy cannot be determined, treatment distribution observed in this cohort may indicate an achievable case distribution among experienced surgeons.
authors.affiliation: Division of Urology, University of Ottawa, Ottawa, ON; ; Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON;
authors.forename: Luke T
authors.initials: LT
authors.lastname: Lavallée
authors.affiliation: Division of Urology, McGill University, Montreal, QC;
authors.forename: Simon
authors.initials: S
authors.lastname: Tanguay
authors.affiliation: Division of Urology, University of Toronto, Toronto, ON;
authors.forename: Michael A
authors.initials: MA
authors.lastname: Jewett
authors.affiliation: Department of Medicine and Urology, Dalhousie University, Halifax, NS;
authors.forename: Lori
authors.initials: L
authors.lastname: Wood
authors.affiliation: Division of Urology, McMaster University, Hamilton, ON;
authors.forename: Anil
authors.initials: A
authors.lastname: Kapoor
authors.affiliation: Department of Urology, Dalhousie University, Halifax, NS;
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Rendon
authors.affiliation: Division of Urology, University of Alberta, Edmonton, AB;
authors.forename: Ronald B
authors.initials: RB
authors.lastname: Moore
authors.affiliation: Division of Urology, Université Laval, Quebec City, QC;
authors.forename: Louis
authors.initials: L
authors.lastname: Lacombe
authors.affiliation: Division of Urology, University of Calgary, Calgary, AB;
authors.forename: Jun
authors.initials: J
authors.lastname: Kawakami
authors.affiliation: Division of Urology, Western University, London, ON;
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Pautler
authors.affiliation: Division of Urology, University of Manitoba, Winnipeg, MB;
authors.forename: Darrel E
authors.initials: DE
authors.lastname: Drachenberg
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC;
authors.forename: Peter C
authors.initials: PC
authors.lastname: Black
authors.affiliation: Division of Urology, Centre hospitalier de l'université de Montreal, Montreal, QC;
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Lattouf
authors.affiliation: Division of Urology, University of Ottawa, Ottawa, ON;
authors.forename: Christopher
authors.initials: C
authors.lastname: Morash
authors.affiliation: Division of Urology, University of Ottawa, Ottawa, ON;
authors.forename: Ilias
authors.initials: I
authors.lastname: Cagiannos
authors.affiliation: Cancer Care Ontario, Toronto, Ontario, Canada.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Division of Urology, University of Ottawa, Ottawa, ON; ; Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON;
authors.forename: Rodney H
authors.initials: RH
authors.lastname: Breau