This study aims to investigate the clinical role of preoperative
pyuria for predicting bacillus Calmette-Guérin (BCG) unresponsiveness in
non-muscle invasive bladder cancer (
NMIBC). We performed a logistic regression analysis on 453 patients with
NMIBC who were treated with BCG
immunotherapy after a
transurethral resection of bladder tumours, to evaluate predictive factors of BCG unresponsiveness. We also analysed univariate and multivariable survival data to estimate the prognostic impact of
pyuria. Of the total study population, 37.6% (170/453) of patients had BCG unresponsiveness. A multivariable logistic regression analysis revealed that a history of upper
urinary tract cancer (odds ratio (OR): 1.86, 95% confidence interval (CI): 1.04-3.32, p-value = 0.035) and the presence of
pyuria (OR: 1.51, 95% CI: 1.01-2.27, p = 0.047) and tumour multiplicity (OR: 1.80, 95% CI: 1.18-2.75, p-value < 0.001) were significant predictors of BCG unresponsiveness. A Cox proportional hazards analysis model showed that
pyuria was a significant prognostic factor for progression-free survival (hazard ratio: 4.51, 95% CI: 1.22-16.66, p = 0.024). A history of upper
urinary tract cancer and the presence of
pyuria and tumour multiplicity are predictive markers of BCG unresponsiveness. For patients with
NMIBC who have preoperative
pyuria, treatment using BCG should be considered cautiously.