title: Minimally invasive partial nephrectomy for single versus multiple renal tumors.
abstract: OBJECTIVE
  We report the perioperative outcomes of robotic/laparoscopic partial nephrectomy for multiple tumors at a single operative session. Outcomes were compared with those of a matched pair cohort treated with partial nephrectomy for a single renal tumor.
  
  
  METHODS
  We retrospectively reviewed a prospectively maintained database from 2001 to 2010 and identified 33 patients who underwent partial nephrectomy for multiple tumors. They were matched 1 to 1 with 33 patients treated with partial nephrectomy for a single tumor. The multiple and single groups were matched for dominant tumor size (3.2 and 3.3 cm, p = 0.61), patient age (60 and 57 years, p = 0.59) and baseline estimated glomerular filtration rate (79.7 and 91.8 ml per minute/1.73 m(2), p = 0.11), respectively.
  
  
  RESULTS
  A total 114 tumors were excised, including 81 in the multiple cohort. There was a median of 2 tumors per kidney (range 2 to 6). In the multiple and single tumor groups estimated blood loss (250 and 235 ml, p = 0.46) and warm ischemia time (19 and 30 minutes, respectively, p = 0.18) were similar. Median operative time (300 vs 217 minutes, p = 0.002) and hospital stay (3 vs 1 days, p = 0.005) were longer in the multiple group. There were 2 conversions to laparoscopic radical nephrectomy per group. Overall, complications developed in 11 (33%) vs 7 patients (21%) treated with partial nephrectomy for multiple vs single tumors (p = 0.40). Median estimated glomerular filtration rate at discharge home was 62.8 vs 67.6 ml per minute/1.73 m(2) in the multiple vs single tumor groups (p = 0.53). Histology confirmed malignancy in 82% and 67% of patients, respectively (p = 0.26). One recurrent tumor in the multiple group had a focal positive margin.
  
  
  CONCLUSIONS
  Robotic/laparoscopic partial nephrectomy can be safely performed for multiple ipsilateral tumors with perioperative outcomes similar to those in patients with a solitary tumor.
authors.affiliation: Center for Advanced Robotic and Laparoscopic Surgery, University of Southern California Institute of Urology, Keck Medical Center of University of Southern California, University of Southern California, Los Angeles, California, USA.
authors.forename: Andre Luis de Castro
authors.initials: AL
authors.lastname: Abreu
authors.forename: Andre K
authors.initials: AK
authors.lastname: Berger
authors.forename: Monish
authors.initials: M
authors.lastname: Aron
authors.forename: Osamu
authors.initials: O
authors.lastname: Ukimura
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Stein
authors.forename: Inderbir S
authors.initials: IS
authors.lastname: Gill
authors.forename: Mihir M
authors.initials: MM
authors.lastname: Desai
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery*; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods*; D012189:Retrospective Studies; D012371:Robotics; D055815:Young Adult