Type 2 diabetes mellitus predicts worse outcomes in patients with high-grade T1 bladder cancer receiving bacillus Calmette-Guerin after transurethral resection of the bladder tumor

Objectives: The aim of this multicenter study was to investigate the prognostic role of type 2 diabetes mellitus (T2DM) comorbidity in a large multi-institutional cohort of patients with primary T1HG/G3 non muscle-invasive bladder cancer (NMIBC) treated with transurethral resection of the bladder (TURB). Materials and methods: A total of 1,172 patients with primary T1 HG/G3 who had NMIBC on re-TURB and who received adjuvant intravesical bacillus Calmette-Guerin therapy with maintenance were included. Endpoints were recurrence-free survival and progression-free survival. Results: A total of 231 (19.7%) of patients had T2DM prior to TURB. Five-year recurrence-free survival estimates were 12.5% in patients with T2DM compared to 36% in patients without T2DM, P < 0.0001. Five-year PFS estimates were 60.5% in patients with T2DM compared to 70.2% in patients without T2DM, P = 0.003. T2DM was independently associated with disease recurrence (hazard ratio = 1.41; 95% confidence interval =1.20-1.66, P < 0.001) and progression (hazard ratio = 1.27; 95% confidence interval = 0.99-1.63, P < 0.001), after adjusting for other known predictive factors such as tumor size, multifocality, T1G3 on re-TURB, body mass index, lymphovascular invasion, and neutrophil-to-lymphocytes ratio. Conclusions: Given the potential implications for management, prospective validation of this finding along with translational studies designed to investigate the underlying biology of such an association are warranted. (C) 2020 Elsevier Inc. All rights reserved.