Surgical margin status after robot assisted radical cystectomy: results from the International Robotic Cystectomy Consortium.

Abstract

PURPOSE: Positive surgical margins at radical cystectomy confer a poor prognosis. We evaluated the incidence and predictors of positive surgical margins in patients who underwent robot assisted radical cystectomy for bladder cancer. MATERIALS AND METHODS: Using the International Robotic Cystectomy Consortium database we identified 513 patients who underwent robot assisted radical cystectomy, as done by a total of 22 surgeons at 15 institutions from 2003 to 2009. After stratification by age group, gender, pathological T stage, nodal status, sequential case number and institutional volume logistic regression was used to correlate variables with the likelihood of a positive surgical margin. RESULTS: Of the 513 patients 35 (6.8%) had a positive surgical margin. Increasing 10-year age group, lymph node positivity and higher pathological T stage were significantly associated with an increased likelihood of a positive margin (p = 0.010, <0.001 and p <0.001, respectively). Gender, sequential case number and institutional volume were not significantly associated with margin positivity. The rate of margin positive disease at cystectomy was 1.5% for pT2 or less, 8.8% for pT3 and 39% for pT4 disease. CONCLUSIONS: Positive surgical margin rates at robot assisted radical cystectomy for advanced bladder cancer were similar to those in open cystectomy series in a large, multi-institutional, prospective cohort. Sequential case number, a surrogate for the learning curve and institutional volume were not significantly associated with positive margins at robot assisted radical cystectomy.