Objective: To evaluate the impact of body mass on recurrence and progression in patients with Ta, T1 urothelial bladder cancer.
Methods: Data from 469 patients with Ta, T1 bladder cancer who were treated with transurethral resection of bladder tumor at our center during 2006-2014 were retrospectively studied. According to body mass index (BMI), patients were divided into three groups: normal weight (BMI < 24 kg/m(2)), overweight (24 kg/m(2) ≤ BMI < 28 kg/m(2)) and obesity (BMI ≥ 28 kg/m(2)). Clinicopathologic features were compared across groups. Kaplan-Meier curves and Cox proportional hazards regression analyses were employed to assess the association between body mass and oncologic outcomes.
Results: Compared with patients with normal weight, overweight and obese counterparts showed significantly shorter recurrence-free or progression-free survival. In multivariate analyses, being overweight was an independent factor for recurrence and obesity was for both recurrence and progression. The presence of diabetes mellitus (DM) was not a strong risk factor for the entire cohort, while it became a significant predictor for both recurrence and progression in the subgroup of overweight and obese patients.
Conclusion: Excessive body mass seems to act as independent risk factors for worse oncologic outcomes of Ta, T1 bladder cancer. Further studies should be carried out to elucidate the exact impact of obesity, DM or even other metabolic disorders.