Comparing Pathologic and Survival Outcomes Between Primary and Secondary Muscle Invasive Bladder Cancer When Treated by Radical Cystectomy With or Without Neoadjuvant Chemotherapy

Abstract

Objective: To compare pathologic and survival outcomes between primary muscle invasive (pMIBC) and secondary muscle invasive (sMIBC) bladder cancer patients who were treated with or without cisplatin-based neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC).

Methods: We reviewed cT2-T4/N0 MIBC patients at our institution between 2010-2019. pMIBC was defined as presenting with > cT2 disease on initial or restaging TURBT with no prior history of bladder cancer. sMIBC was defined as prior history of NMIBC that was treated with at least one induction course of BCG that progressed to MIBC. Outcomes analyzed included pathologic downstaging rates defined as <pT2/N0, pathologic complete response rates (pT0/N0), and survival outcomes (RFS, CSS, OS). Survival outcomes were analyzed using the Kaplan-Meier Method or Gray's test with log rank. Cox Proportional Hazards and semiparametric hazards models proposed by Fine and Gray were constructed to identify predictors of oncologic outcomes.

Results: 333 patients were included in the analysis (sMIBC: 48 vs pMIBC: 285). There were no differences in pathologic downstaging (sMIBC: 54% vs pMIBC: 51%, P = .67) or pathologic complete response (sMIBC: 33% vs pMIBC: 28, P = .46). Survival analysis showed no differences when patients were treated with NAC+RC in oncologic outcomes. On regression analysis, only >pT2 and N+ disease were predictors of poorer CSS and OS. Separate analysis of sMIBC patients whom underwent RC only (N = 61), demonstrated inferior oncologic outcomes to other cohorts (P < .01).

Conclusion: There were no differences in pathologic response or survival between pMIBC and sMIBC patients when managed with NAC and RC.