title: The learning curve in pancreatic surgery.
abstract: BACKGROUND
  Pancreatic surgery is technically complex. We hypothesized that a learning curve existed for pancreaticoduodenectomy even for surgeons who had completed their training.
  
  
  METHODS
  During 1990 to 2004, we studied 650 consecutive patients who underwent pancreaticoduodenectomy by 3 surgeons who began their attending careers at 1 center. Operative time, estimated blood loss (EBL), length of hospital stay (LOS), and the status of resection margins (for pancreatic adenocarcinoma) were analyzed. The chi2, independent t test and Mann-Whitney U test were used to evaluate differences in categorical, normally distributed continuous, and non-normally distributed continuous variables, respectively. Using serial groups of 30 cases, median operative time, EBL, and LOS were calculated and the trend over time modeled using third-order polynomial equations. Trends in retroperitoneal margin positivity (R0/R1) were assessed.
  
  
  RESULTS
  From the first 60 cases per surgeon to the second 60 cases per surgeon, the median EBL dropped (1100 vs 725 mL, P < .001), operative time decreased (589 vs 513 minutes, P < .001), and LOS decreased (15 vs 13 days, P = .004). The proportion of microscopically positive or suspicious margins also decreased from the surgeons' first 60 cases each to the second 60 cases (30% vs 8%, P < .001). Extended analysis of a single surgeon's cases suggested that additional experience provided further incremental improvement (P < .001).
  
  
  CONCLUSIONS
  Pancreaticoduodenectomy has an inherent learning curve. After 60 cases, surgeons achieved significantly decreased EBL, operative time, and LOS, and carried out more margin-negative resections. Improvement in measured outcomes continues during the operative career.
authors.affiliation: Department of Surgery and the UMass Memorial Cancer Center, University of Massachusetts Medical School, Worcester, MA 01605, USA. tsengj@ummhc.org
authors.forename: Jennifer F
authors.initials: JF
authors.lastname: Tseng
authors.forename: Peter W T
authors.initials: PW
authors.lastname: Pisters
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Lee
authors.forename: Huamin
authors.initials: H
authors.lastname: Wang
authors.forename: Henry F
authors.initials: HF
authors.lastname: Gomez
authors.forename: Charlotte C
authors.initials: CC
authors.lastname: Sun
authors.forename: Douglas B
authors.initials: DB
authors.lastname: Evans
mesh_terms: D000368:Aged; D016063:Blood Loss, Surgical / Q000706:statistics & numerical data*; D002983:Clinical Competence / Q000706:statistics & numerical data*; D005260:Female; D013502:General Surgery / Q000193:education; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D016577:Pancreaticoduodenectomy / Q000009:adverse effects*; D011214:Practice, Psychological; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome