Higher nodal yield with robot-assisted pelvic lymph node dissection for bladder cancer compared to laparoscopic dissection: implications for more accurate staging.

OBJECTIVES

To compare the lymph node (LN) yield and adequacy of laparoscopic pelvic lymph node dissection (L-PLND) and robot-assisted PLND (R-PLND), as PLND is a fundamental component of radical cystectomy (RC) for bladder cancer (BCa), where a positive status is the most powerful predictor of disease recurrence and survival.

PATENTS AND METHODS

We retrospectively reviewed patients undergoing RC with PLND for BCa from January 2007 to July 2019 and grouped them in to L- and R-PLND. Until 2011, patients underwent a standard PLND (S-PLND) with the cranial limit as bifurcation of common iliac artery. Since 2012, an extended PLND (E-PLND) up to aortic bifurcation has been performed. An adequate S- and E-PLND were defined as those that yielded at least 10 and 16 LNs, respectively. The groups were compared for LN yield and adequacy of PLND.

RESULTS

During the study period, 305 patients underwent minimally invasive RC in our centre, of which 274 (89.8%) underwent a concomitant PLND (98 L-PLND, 176 R-PLND). R-PLND resulted in a significantly greater median LN yield compared to L-PLND, both in the S-PLND (16 vs 11, < 0.001) and the E-PLND (19 vs 14, < 0.001) eras. Also, a significantly higher proportion of patients in the R-PLND group had an adequate PLND compared to the L-PLND group. Surgical approach to PLND (R- vs L-PLND) was the only variable that was significantly associated with an adequate PLND on both univariable (odds ratio [OR] 1.860, 95% confidence interval [CI] 1.114-3.105; = 0.01) and multivariable (OR 2.109, 95% CI 1.222-3.641; = 0.007) analyses.

CONCLUSION

R-PLND leads to a higher LN yield and a greater probability of an adequate PLND compared to L-PLND for both standard and extended templates. Therefore, the robot-assisted approach would lead to more accurate staging following RC with PLND.