Partial and Radical Cystectomy Provides Equivalent Oncologic Outcomes in Bladder Cancer when Combined with Adequate Lymph Node Dissection: A Population-based Study

Purpose: To compare the oncologic outcomes of bladder cancer (BCa) patients after partial cystectomy (PC) or radical cystectomy (RC) combined with lymph node dissection (LND).

Methods: Relevant data from BCa patients who had >3 lymph nodes (LNs) removed were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. Different thresholds of LN count in LND were tested to eliminate potential selection bias, and the optimal threshold was applied to screen patients who underwent adequate LND. After propensity score matching, the oncologic outcomes after PC or RC were compared in patients who underwent adequate LND.

Results: After preliminary screening, 6,785 BCa cases diagnosed between 2004 and 2015 with removal of > 3 LNs were enrolled in the analysis, including 633 (9.3%) PC cases and 6,152 (90.7%) RC cases. The PC and RC groups presented entirely different profiles in clinical parameters such as sex, T stage, number of lymph nodes (LNs) removed, and adjuvant therapy. In particular, the LN-positive rate and count were higher in the RC group, even after adjusting for other confounding factors. After comparison using different thresholds, the LN positive rate and count were similar when the LN count in LND was restricted to > 12. In patients who had > 12 LNs removed, after propensity score matching, PC and RC presented similar oncologic outcomes. Further exploration found that the prognosis of patients was associated with age, T stage, and the number of positive LNs.

Conclusion: PC and RC could provide equivalent oncologic outcomes in BCa when combined with adequate LND. The conclusion needs further validation in future studies.