Recurrence and its association with overall survival (OS) in muscle-invasive bladder cancer (MIBC) patients undergoing radical cystectomy (RC): A real-world analysis.

Abstract

705 Background: MIBC is a heterogenous disease, encompassing T2-T4 tumors with or without nodal disease (T1-T4aN1). A primary treatment modality for MIBC is RC, often supplemented by neoadjuvant (NAD) and/or adjuvant (AD) therapies for select patients. Despite RC, patients with MIBC have a high risk of disease recurrence and progression. This study aimed to describe the real-world, contemporary impact of disease stage at diagnosis and treatment received on cancer recurrence and OS and examine the association between recurrence and OS. Methods: This retrospective study quantified recurrence and OS and the association of recurrence with OS among patients with MIBC (T2-T4aN0M0/T1-T4aN1M0) who had RC. Adult MIBC patients undergoing RC between January 1, 2008 and July 1, 2023 were identified using the U.S. ConcertAI Patient360 Bladder Cancer electronic medical record database in a predominantly community-based oncology setting. Index date was defined as the date of RC. Recurrence was defined as the first recorded disease progression >7 days after RC. Proportions of recurrence and OS were analyzed using Kaplan-Meier analysis overall and stratified by disease stage and treatment received. Association of recurrence with OS was assessed using Cox regression adjusted for patient characteristics. Results: 783 RC-treated MIBC patients met study inclusion criteria (median age 68 years; male 79%; White 88%; de novo MIBC 77%; urothelial histology 77%), with median follow up of 26 months (IQR: 11–48). At MIBC diagnosis, 73% were clinical stage T2N0, 21% were T3/4aN0, and 6% were T1-T4aN1. Almost half the patients (48%) underwent RC alone, while 46% received NAD+RC, 4% received RC+AD, and 3% received NAD+RC+AD. Over time, NAD use doubled from 30% (2011–2013) to 62% (2020–2022). Among patients who received NAD and had evaluable pathological staging (n=240), 26% achieved pathological complete response (pT0pN0). The overall 5-year recurrence rate was 45%, with variation by disease stage and treatment (Table). The 5-year OS was 48% overall and was significantly lower for patients with recurrence compared with those without (17% vs 69%, p<0.0001). Mortality was 4.4 times higher [95% CI: 3.5, 5.6] among those with recurrence compared to those without. Conclusions: MIBC patients undergoing RC had high recurrence rates, irrespective of disease stage at diagnosis or treatment modality received. Recurrence was associated with increased mortality rate. These findings underscore the substantial clinical burden for surgically treated MIBC patients and the need for more effective treatments that can delay or prevent recurrence and improve OS. Recurrence and OS by stage and treatment group. 5-Year Recurrence Rate % 5-Year OS Rate % Stage at MIBC Diagnosis T2N0 42 50 T3/T4aN0 52 47 T1-T4aN1 59 31 Treatment Group RC Alone 48 44 NAD+RC 39 56 RC+AD 67 29 NAD+RC+AD N/A 26