Extended pelvic lymph node dissection in muscle invasive bladder cancer.

Abstract

Bilateral pelvic lymph node dissection (PLND) at the time of radical cystectomy (RC) provides important staging information and oncologic benefit in patients with bladder cancer. The optimal extent of the PLND remains controversial. Our aim is to highlight nodal mapping studies and the data that guides optimization of both staging and oncologic outcomes. We then review contemporary randomized trials studying the extent of PLND. A recent randomized trial (RCT) powered for a 15% improvement in recurrence-free survival (RFS) of extended (e) over limited (l)PLND was completed but failed to identify this large difference in outcome. Concerns over study design limit the ability to interpret the oncologic results. Importantly, ePLND minimally changed surgical morbidity. An ongoing, similar RCT (SWOG S1011) powered to detect a 10% difference in RFS has completed accrual, but no published outcomes are available. RC and ePLND can provide cure in 33% of LN positive bladder cancer patients. Current data support a 5% improvement in RFS if ePLND is routinely used in MIBC patients. Two randomized trials powered to identify much larger (15 and 10%) improvements in RFS are unlikely to identify such an ambitious benefit by extending the PLND.