Comparison of Perioperative and Early Oncologic Outcomes between Open and Robotic Assisted Laparoscopic Prostatectomy in a Contemporary Population Based Cohort

Abstract

Purpose: We compared rates of positive surgical margins, use of postoperative radiation therapy, and perioperative outcomes between robotic assisted laparoscopic and open radical prostatectomy in a contemporary population based cohort.

Materials and methods: In the National Cancer Data Base from 2010 through 2011 patients who underwent robotic assisted laparoscopic prostatectomy (73,131) and open radical prostatectomy (23,804) for nonmetastatic prostate adenocarcinoma were identified. Covariates included age, race, Charlson comorbidity index, prostate specific antigen, biopsy Gleason score, clinical stage, final Gleason score, pathological T stage, lymph node dissection, nodal status, facility type, hospital volume and year of surgery. Multivariable logistic regression was used to identify factors associated with positive surgical margins, use of adjuvant/salvage radiation therapy, prolonged length of stay, readmission and 30-day mortality. Outcomes were also compared in 1:1 propensity matched cohorts.

Results: Analysis of propensity matched cohorts showed robotic assisted laparoscopic prostatectomy reduced the risk of positive surgical margins (OR 0.88, 95% CI 0.83-0.93, p <0.01), the use of radiation therapy (OR 0.71, 95% CI 0.63-0.80, p <0.01) and 30-day mortality (OR 0.28, 95% CI 0.13-0.60, p <0.01). The protective effect of robotic assisted laparoscopic prostatectomy for positive surgical margins was found in patients with pT2 disease only (pT2-OR 0.85, 95% CI 0.79-0.91, p <0.01; pT3-OR 0.94, 95% CI 0.86-1.04, p=0.2). Similar results were obtained using multivariable regression.

Conclusions: In a contemporary large national cohort, robotic assisted laparoscopic prostatectomy was independently associated with clinically meaningful reductions in positive surgical margins, postoperative radiation therapy and 30-day mortality compared to open radical prostatectomy. The oncologic benefit was primarily in patients with organ confined disease. Limitations were those associated with any observational study, namely the potential for bias due to unmeasured confounders.

Keywords: mortality; prostatectomy; prostatic neoplasms; robotics; treatment outcome.