Progression to detrusor muscle invasion during urothelial carcinoma surveillance is associated with poor prognosis

Abstract

Objective: To evaluate survival in patients after radical cystectomy (RC) who presented with non-muscle-invasive urothelial carcinoma and progressed to muscle invasion during surveillance. Our secondary objective was to evaluate the association between clinical factors before RC and survival.

Patients and methods: In all, 981 consecutive Mayo Clinic RC patients without a history of radiation or systemic chemotherapy were reviewed. Of these, 190 had RC after they progressed from non-muscle invasive disease to muscle invasion (progressed to ≥pT2). These patients were compared to 310 patients who had RC before muscle invasion (≤pT1), and 481 patients who had muscle invasion at initial presentation (presented with ≥pT2). Survival estimates were generated using the Kaplan-Meier method and compared using the log-rank test, while adjusted analyses were performed using Cox proportional hazard regression models.

Results: Patients who progressed to muscle invasion on surveillance had a higher risk of death than patients who initially presented with muscle invasion (overall survival hazard ratio [HR] 1.3; 95% confidence interval [CI] 1.0, 1.5). The estimated 5-year cancer-specific survival was 85.4% for patients presenting with ≤pT1, 52.9% for patients who progressed to ≥pT2, and 62.4% for patients who presented with ≥pT2 (P < 0.001). The corresponding 5-year overall survival rates were 70.0%, 42.1%, and 49.5% (P < 0.001). Of the patients who initially presented with non-muscle-invasive disease, progression to muscle invasion was associated with increased risk of cancer-specific death (adjusted HR 2.38; 95% CI 1.6, 3.5). Lack of information about patients who presented without muscle invasion and never received RC is the major limitation of this study.

Conclusions: Despite close surveillance, many patients who progress to muscle invasion will die from bladder cancer. Patients who progress to muscle invasion on surveillance seem to have particularly aggressive disease and may benefit from multimodal treatments.

Keywords: prognosis; urinary bladder; urothelial carcinoma.