Urinary microbiota in bladder cancer: insights into pathogenesis, diagnosis, and therapeutic potential

Bladder cancer is a prevalent urinary malignancy with high global incidence and mortality. Despite advances in diagnosis and treatment, challenges persist, particularly due to high recurrence rates and unpredictable progression. Recent evidence highlights the role of urinary tract microbiota in BC initiation, progression, and recurrence. The urinary tract, once thought sterile, is now recognized as a complex microbial environment influencing local immunity and carcinogenesis. Differences in microbiota composition between cancer patients and controls, as well as variations by gender, age, and lifestyle factors like smoking, have been observed. The microbiota may impact tumor staging, grading, recurrence, and treatment responses, particularly to Bacillus Calmette-Guérin therapy. Mechanisms include immune modulation, inflammation, and epithelial barrier disruption. This review synthesizes current research on urinary microbiota's role in BC, emphasizing its potential as a biomarker and therapeutic target. Large-scale studies are needed to better understand these associations and develop microbiota-based strategies for improved BC management.