title: Exploring the learning curve, pathological outcomes and perioperative morbidity of laparoscopic partial nephrectomy performed for renal mass.
abstract: OBJECTIVE
  We investigated the learning curve, pathological results and perioperative morbidity of laparoscopic partial nephrectomy (LPN).
  
  
  METHODS
  The records of all LPN cases at our institution between January 1999 and March 2004 were reviewed. Of 223 cases 217 (97.3%) were performed for an enhancing renal mass.
  
  
  RESULTS
  Mean tumor size was 2.6 cm (range 1 to 10) and 95.4% of patients had a normal contralateral kidney. Transient vascular control was performed in 75.1% of cases. Mean operative time (186 minutes) decreased with surgeon experience (p = 0.003) but was independent of tumor size (p = 0.964). Mean warm ischemia time (27.6 minutes) depended on tumor size (p = 0.005) but not on experience (0.964). Mean blood loss was 385 cc and the perioperative transfusion rate was 6.9%. Postoperative complications occurred in 23 cases (10.6%) with the most common being ileus (1.8%), bleeding (1.8%) and urinary leakage (1.4%). Although the mean serum creatinine change after LPN was a function of tumor size (p <0.001), it was clinically insignificant (0.13 mg/dl). No significant relationship was observed between warm ischemia time and creatinine change (p = 0.262). The final pathological evaluation revealed renal cell carcinoma in 144 patients (66.4%) and the overall positive margin rate was 3.5%. Only 2 renal cell carcinoma recurrences in the operated kidney (1.4%) were identified (mean followup +/- SD 24 +/- 12 months).
  
  
  CONCLUSIONS
  LPN is an effective approach for treating small renal masses with low perioperative morbidity. Contrary to previous reports, more than 30% of the enhancing renal lesions excised in this series were found to be benign on final pathological evaluation.
authors.affiliation: The James Buchanan Brady Urological Institute, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA. rlink5@jhmi.edu
authors.forename: Richard E
authors.initials: RE
authors.lastname: Link
authors.forename: Sam B
authors.initials: SB
authors.lastname: Bhayani
authors.forename: Mohammed E
authors.initials: ME
authors.lastname: Allaf
authors.forename: Ioannis
authors.initials: I
authors.lastname: Varkarakis
authors.forename: Takeshi
authors.initials: T
authors.lastname: Inagaki
authors.forename: Craig
authors.initials: C
authors.lastname: Rogers
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Su
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Jarrett
authors.forename: Louis R
authors.initials: LR
authors.lastname: Kavoussi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000601:surgery*; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000193:education* / Q000379:methods*