BCG is one of the vaccines legally required by the immunization program and is given to every newborn to prevent tuberculosis. However, few people know that BCG vaccine has another purpose – to treat and prevent recurrence of bladder tumors. Currently, 90% to 95% of bladder cancers in clinical practice are metastatic epithelial cell carcinomas, which mostly present as superficial carcinomas in the early stages of the disease. The treatment of superficial bladder cancer mainly relies on transurethral resection or electrocautery. However, after transurethral resection of superficial bladder cancer, the recent tumor recurrence rate is as high as 50% to 90%, and the long-term recurrence rate is almost 100%. Bladder instillation with BCG after surgery is an effective way to treat and prevent recurrence of bladder cancer.
Intravesical BCG drips trigger an inflammatory response and promote an anti-tumor immune response. This treatment is clinically effective in 50-70% of patients without muscle-invasive bladder cancer. Successful treatment relies on repeated live BCG drips given immediately after tumor resection. The use of BCG bladder irrigation for intermediate and high-grade uroepithelial noninvasive papillary carcinoma is now a standard practice recommended by the international urology trade associations, with overall efficacy superior to chemotherapeutic drug infusion.