Effect of diabetes mellitus and metformin use on oncologic outcomes of patients treated with radical cystectomy for urothelial carcinoma
Abstract
Objectives: Evidence suggests a positive effect of metfoimin on cancer incidence and outcome. To date, the effect of metfoimin use on prognosis in urothelial carcinoma of the bladder (UCB) remains uninvestigated.
We tested the hypothesis that metformin use affects oncologic outcomes of patients treated with radical cystectomy for UCB. Methods and materials: We retrospectively evaluated 1,502 patients treated at 4 institutions with radical cystectomy and pelvic lymphadenectomy without neoadjuvant therapy.
Cox regression models addressed the association of diabetes mellitus (DM) and metformin use with disease recurrence, cancer-specific mortality, and any-cause mortality. Results: A total of 200 patients (13.3%) had DM, 80 patients (5.3%) used metformin.
Within a median follow-up of 34 months, 509 patients (33.9%) experienced disease recurrence, 402 patients (26.8%) died of UCB, and 551 patients (36.7%) died from any cause. In univariable Cox regression analyses, DM without metfonnin use was associated with increased risk of disease recurrence (hazard ratio RIR]: 1.40, 95% confidence interval ICII 1.05 1.87, P = 0.02), cancer-specilic mortality (HR: 1.60, 95% CI 1.17 2.17, P = 0.003), and any-cause mortality (HR: 1.55, 95% CI 1.18 2.03, P = 0.002), whereas mettOrmin use was associated with decreased risk of disease recurrence (IIR: 0.61. 95% CI 0.37 0.98, P = 0.04), cancer-specific mortality (11R: 0.56, 95% CI 0.33 0.97, P = 0.04), and any-cause mortality (IIR: 0.54, 95% CI 0.33 0.88, P = 0.01).
In multivariable Cox regression analyses, DM treated without metformin use remained associated with worse cancer-specific mortality (HR: 1.53, 95% CI 1.12-2.09, P = 0.007) and any-cause mortality (HR: 1.52, 95% CI 1.16-2.00, P = 0.003) but not disease recurrence.