Extended Versus Limited Lymph Node Dissection in Bladder Cancer Patients Undergoing Radical Cystectomy: Survival Results from a Prospective, Randomized Trial

Abstract

Background: The extent of lymph node dissection (LND) in bladder cancer (BCa) patients at the time of radical cystectomy may affect oncologic outcome.

Objective: To evaluate whether extended versus limited LND prolongs recurrence-free survival (RFS).

Design, setting, and participants: Prospective, multicenter, phase-III trial patients with locally resectable T1G3 or muscle-invasive urothelial BCa (T2-T4aM0).

Intervention: Randomization to limited (obturator, and internal and external iliac nodes) versus extended LND (in addition, deep obturator, common iliac, presacral, paracaval, interaortocaval, and para-aortal nodes up to the inferior mesenteric artery).

Outcome measurements and statistical analysis: The primary endpoint was RFS. Secondary endpoints included cancer-specific survival (CSS), overall survival (OS), and complications. The trial was designed to show 15% advantage of 5-yr RFS by extended LND.

Results and limitations: In total, 401 patients were randomized from February 2006 to August 2010 (203 limited, 198 extended). The median number of dissected nodes was 19 in the limited and 31 in the extended arm. Extended LND failed to show superiority over limited LND with regard to RFS (5-yr RFS 65% vs 59%; hazard ratio [HR]=0.84 [95% confidence interval 0.58-1.22]; p=0.36), CSS (5-yr CSS 76% vs 65%; HR=0.70; p=0.10), and OS (5-yr OS 59% vs 50%; HR=0.78; p=0.12). Clavien grade ≥3 lymphoceles were more frequently reported in the extended LND group within 90d after surgery. Inclusion of T1G3 tumors may have contributed to the negative study result.

Conclusions: Extended LND failed to show a significant advantage over limited LND in RFS, CSS, and OS. A larger trial is required to determine whether extended compared with limited LND leads to a small, but clinically relevant, survival difference (ClinicalTrials.gov NCT01215071).

Patient summary: In this study, we investigated the outcome in bladder cancer patients undergoing cystectomy based on the anatomic extent of lymph node resection. We found that extended removal of lymph nodes did not reduce the rate of tumor recurrence in the expected range.

Keywords: Bladder cancer; Cancer-specific survival; Cystectomy; Lymph node dissection; Overall survival; Recurrence-free survival.