Suboptimal use of pelvic lymph node dissection: Differences in guideline adherence between robot-assisted and open radical prostatectomy

Introduction: Our aim was to assess adherence to National Comprehensive Cancer Network (NCCN) and American Urological Association (AUA) guidelines for pelvic lymph node dissection (PLND) at the time of either robot-assisted (RARP) or open radical prostatectomy (ORP). Methods: We relied on the Surveillance, Epidemiology, and End Results-Medicare linked database and focused on localized prostate cancer (PCa) patients who were treated with either RARP or ORP between October 2008 and December 2009. Categorical and multivariable logistic regression analyses targeted two endpoints: 1) probability of guideline-recommended PLND; and 2) probability of no PLND, when not guideline-recommended. Results: Among 5268 PCa patients, adherence to NCCN PLND guideline was 56.9% during RARP and 76.5% during ORP (odds ratio [OR] 0.4, 95% confidence interval [CI] 0.3–0.6). AUA PLND guideline adherence was 68.1% during RARP and 82.4% during ORP (OR 0.7, 95% CI 0.5–0.9). When PLND was not recommended, it was more frequently performed during ORP according to either NCCN (OR 3.7, 95% CI 3.5–3.9) or AUA (OR 2.7, 95% CI 2.6–2.8). According to the NCCN guideline, at recommended PLND in ORP patients, 6.3% harboured lymph node invasion (LNI) (number needed to treat [NNT] 16) vs. 3.2% at RARP (NNT 31). According to the AUA guideline, at recommended PLND in ORP patients, 12.3% harboured LNI (NNT 8) vs. 5.1% RARP (NNT 19). Conclusions: Adherence to NCCN and AUA PLND guidelines was lower during RARP than during ORP when PLND was recommended. The rate of non-recommended PLND was also higher during ORP than during RARP. Technical considerations may be at play.