Bladder tumor Resection Weight as a Prognostic Factor for Recurrence and Progression in Patients With High-Risk Non-Muscle Invasive Bladder Treated With BCG

Predicting outcomes of patients with high-risk non-muscle invasive bladder cancer (HR-NMIBC) is critical. Here, we evaluate whether bladder tumor resection weight might serve as a prognostic factor for recurrence and progression of HR-NMIBC patients treated with Bacillus Calmette-Guérin (BCG). In this retrospective, single-centre study in the UK, we analysed a consecutive cohort of HR-NMIBC patients who have received adequate intravesical BCG immunotherapy between 2009 and 2019. Univariable and multivariable Cox proportional hazards models were used to assess the association of resection weight and established predictors with recurrence and progression. A total of 187 HR-NMIBC patients were analysed. The median resection weight was 1.4g (range: 0.2-28.5g). Within a median follow-up of 41 months, 58 (31%) tumors recurred and 19 (10%) progressed. Fifty-four patients (29%) died from any cause and 16 (9%) died from bladder cancer. Both the risk of recurrence (P = .007) and progression (P = .019) increased with rising resection weight. On the multivariable analysis, a resection weight of ≥ 2g and ≥ 3g conferred a 4.35-fold and a 9.03-fold increased risk of bladder cancer recurrence (P < .001) and progression (P < .001), respectively. The addition of resection weight improved the C index of multivariable standard prognostic models to a clinically significant extent (+ 3.8% for recurrence, + 4.3% for progression). In our HR-NMIBC patient cohort treated with BCG, bladder tumor resection weight was associated with disease recurrence and progression. Its addition improves discrimination of standard prognostic factors. Measurement may therefore be considered for routine clinical practice. Bladder cancer is a common and difficult to treat urological malignancy. Predicting high risk non-muscle invasive bladder cancer progression could alter management. This project has provided evidence that resection weight is associated with recurrence and progression. Measurement should be considered in routine clinical practice.