title: Increasing use of kidney sparing approaches for localized renal tumors in a community based health system: impact on renal functional outcomes.
abstract: OBJECTIVE
  The use of partial nephrectomy and other kidney sparing approaches in national databases lags far behind practice patterns at major academic centers. The reasons and impact of this disparity are largely unknown. We examined the trend in kidney sparing approaches in a community based health care system to examine associated factors and impact on renal function.
  
  
  METHODS
  We evaluated the records of all patients who underwent intervention for suspicious renal lesions at a single health care system between 1998 and 2010. Demographic, pathological and functional data were collected in an institutional review board approved database.
  
  
  RESULTS
  During the 12 study years a kidney sparing approach was used in 35% of patients with localized renal tumors. A clear increase in the proportion of patients undergoing a kidney sparing approach was observed, including 11%, 23% and 49% during successive 4-year periods. A kidney sparing approach was used in 81% of patients with tumors 4 cm or less during 2009 to 2010. Although high volume (greater than 20 cases annually), more recently graduating (2001 or later) and fellowship trained surgeons had higher kidney sparing approach use overall (each p <0.03), the proportion of patients who underwent a kidney sparing approach increased with time in all study groups (p <0.0001). The renal functional loss in patients who underwent a kidney sparing approach and radical nephrectomy was 2% and 30%, respectively (p <0.001).
  
  
  CONCLUSIONS
  The kidney sparing approach rate in a community based health care system can approach rates at major academic centers. This practice pattern appears related to the addition of recent graduates and urological oncologists but also to a change in long-standing practice patterns of other community urologists. These data suggest that the use of kidney sparing approaches nationwide and the associated renal functional benefits may continue to increase.
authors.affiliation: Spectrum Health Hospital System and Michigan State University College of Human Medicine, Grand Rapids, Michigan 49546, USA. brian.lane@spectrum-health.org
authors.forename: Brian R
authors.initials: BR
authors.lastname: Lane
authors.forename: Henry
authors.initials: H
authors.lastname: Chen
authors.forename: Michael
authors.initials: M
authors.lastname: Morrow
authors.forename: John G
authors.initials: JG
authors.lastname: Anema
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Kahnoski
mesh_terms: D000368:Aged; D005260:Female; D005919:Glomerular Filtration Rate; D006764:Hospitals, Community; D006801:Humans; D007672:Kidney Cortex; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods*; D011859:Radiography