Extended vs Standard Lymph Node Dissection at the Time of Radical Cystectomy for Bladder Cancer

The oncologic benefit of the extent of lymphadenectomy at the time of radical cystectomy (RC) for bladder cancer is uncertain. Although two randomized clinical trials have reported no difference in disease-free or overall survival for extended LND (eLND) compared to standard LND (sLND), real-world data are lacking. We therefore emulated a pragmatic clinical trial using a large, nationwide dataset.

We used SEER-Medicare to emulate the LEA AUO AB 25/02 clinical trial. We identified adults 66-79 years diagnosed with high-grade T1 or cT2-T4a, Nany, M0 urothelial carcinoma of the bladder from 2000 to 2017 and treated with RC with LND. sLND and eLND were defined as removal of 4-11 and >12 lymph nodes, respectively. A propensity score (PS) was estimated for receipt of eLND. Associations of LND type with cancer-specific (CSS) and overall survival (OS) were evaluated.

A total of 1204 patients were included in the study cohort, of whom 794 underwent eLND and 410 underwent sLND. Pre-treatment characteristics were well-balanced after PS adjustment. Compared to sLND, eLND was not associated with a statistically significant difference in 5-year CSS (68% vs 64%; HR 0.83, 95% CI 0.64-1.06; P = .14) or OS (56% vs 55%; HR 0.82; 95% CI 0.68-1.01; P = .06). Results were similar when examining heterogeneity of treatment effects according to T stage, pN stage and age.

In observational analyses designed to emulate the completed LEA AUO AB 25/02 trial, eLND was not associated with improved CSS or OS compared to sLND among patients undergoing RC.