title: Propensity-score matched analysis comparing robot-assisted with laparoscopic partial nephrectomy.
abstract: OBJECTIVE
  To compare the peri-operative and early renal functional outcomes of robot-assisted partial nephrectomy (RAPN) and laparoscopic partial nephrectomy (LPN) for kidney tumours.
  
  
  METHODS
  A total of 237 patients fulfilling the selection criteria were included, of whom 146 and 91 patients were treated with LPN and RAPN, respectively. To adjust for potential baseline confounders, propensity-score matching was performed. A favourable outcome was defined as a warm ischaemia time (WIT) of ≤20 min, negative surgical margins, no surgical conversion, no Clavien ≥3 complications and no postoperative chronic kidney disease (CKD) upstaging. Descriptive statistics and multivariable logistic regression analyses were performed before and after propensity-score matching.
  
  
  RESULTS
  Within the propensity-score-matched cohort, the RAPN group was associated with significantly lower estimated blood loss (EBL; 156 vs 198 mL, mean difference [MD] = -42; P = 0.025), a shorter WIT (22.8 vs 31 min, MD = -8.2; P < 0.001) and a higher proportion of malignant lesions (88.4 vs 67.5%; odds ratio [OR]: 2.6; 95% confidence interval [CI]: 1.2-5.67; P = 0.023). With regard to early renal functional outcomes, the mean last estimated glomerular filtration rate was 95.8 and 89.4 mL/min per 1.73 m(2) (MD = 6.4; P = 0.01), with a mean ± sd percentage change of -4.8 ± 17.9 and -12.2 ± 16.6 (MD = 7.4; P = 0.018) in the RAPN and LPN groups, respectively. The intra-operative complication rate was significantly lower in the RAPN group (1.3 vs 11.7%; OR 0.1, 95% CI 0.01-0.81; P = 0.018). On multivariable analysis, surgical approach (RAPN vs LPN, OR 5.457, 95% CI 2.075-14.346; P = 0.001), Charlson Comorbidity Index (OR 0.223; 95% CI 0.062-0.811; P = 0.023), diameter-axial-polar score (OR 0.488, 95% CI 0.329-0.723; P < 0.001) and preoperative CKD stage (OR 3.189, 95% CI 1.204-8.446; P = 0.020) were found to be independent predictors of obtaining a favourable outcome.
  
  
  CONCLUSIONS
  After adjusting for potential treatment selection biases, RAPN was found to be superior to LPN for peri-operative outcomes (EBL, WIT and intra-operative complications) and early renal functional preservation.
authors.affiliation: Department of Urology, Changhai Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Zhenjie
authors.initials: Z
authors.lastname: Wu
authors.forename: Mingmin
authors.initials: M
authors.lastname: Li
authors.forename: Shangqing
authors.initials: S
authors.lastname: Song
authors.forename: Huamao
authors.initials: H
authors.lastname: Ye
authors.forename: Qing
authors.initials: Q
authors.lastname: Yang
authors.forename: Bing
authors.initials: B
authors.lastname: Liu
authors.forename: Chen
authors.initials: C
authors.lastname: Cai
authors.forename: Bo
authors.initials: B
authors.lastname: Yang
authors.forename: Liang
authors.initials: L
authors.lastname: Xiao
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.forename: Chen
authors.initials: C
authors.lastname: Lü
authors.forename: Xu
authors.initials: X
authors.lastname: Gao
authors.forename: Chuanliang
authors.initials: C
authors.lastname: Xu
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Gao
authors.forename: Jianguo
authors.initials: J
authors.lastname: Hou
authors.forename: Linhui
authors.initials: L
authors.lastname: Wang
authors.forename: Yinghao
authors.initials: Y
authors.lastname: Sun
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000009:adverse effects* / Q000379:methods*; D059351:Organ Sparing Treatments / Q000009:adverse effects / Q000379:methods; D011183:Postoperative Complications / Q000209:etiology; D057216:Propensity Score; D012189:Retrospective Studies; D065287:Robotic Surgical Procedures / Q000009:adverse effects* / Q000379:methods*; D016896:Treatment Outcome
keywords: complications; functional outcomes; laparoscopic partial nephrectomy; nephron-sparing surgery; robot-assisted partial nephrectomy