Impact of BMI Category on Recurrence and Progression of Nonmuscle Invasive Bladder Cancer Prognosis

Objective: To assess the association of being overweight or obese with Nonmuscle invasive bladder cancer (NMIBC) recurrence, stage progression, and grade progression.

Methods: Patients with NMIBC were included and categorized into 3 groups based on their body mass index (BMI): normal weight, overweight, and obese. Recurrence was defined as any histologically proven bladder cancer on subsequent transurethral resection of bladder tumor (TURBT). Progression was defined as upgrading from low to high grade, upstaging to pT1 from pTa, or to muscle-invasion from pT1 disease.

Results: A total of 457 patients were analyzed, 135 (29.5%) had normal weight, 192 (42.6%) were overweight, and 130 (28.4%) were obese, with a median BMI of 27.1 (24.4-30.7) Kg/m2. The study found no significant difference in the time to recurrence, stage progression, and grade progression within the BMI categories (P < .05). Additionally, no increased risk was observed in BMI categories (Obesity recurrence HR: 1.067, CI 95%: 0.783-1.453; Obesity stage progression HR: 1.315, 95% CI: 0.635-2.724; Obesity grade progression HR: 0.586, 95% CI: 0.195-1.760).

Conclusions: In our cohort, body weight category showed no association with NMIBC recurrence, stage progression, or grade progression. These findings highlight the need to identify other potential risk factors that could improve NMIBC risk stratification. Further studies are warranted to validate our results and explore additional predictors of NMIBC outcomes.