ABSTRACT
The objective of this study was to evaluate the risk of recurrence in patients with intermediate-risk non-muscle-invasive bladder cancer (NMIBC) after intravesical instillation with chemotherapeutic agents or Bacillus Calmette-Guerin (BCG) therapy. A cohort of 746 patients with intermediate-risk NMIBC comprised the study group. The primary outcome was time to first recurrence. The recurrence rates of the transurethral resection (TUR) alone, chemotherapy, and BCG groups were determined using Kaplan-Meier analysis. Risk factors for recurrence were identified using Cox regression analysis. In total, 507 patients (68.1%), 78 patients (10.5%), and 160 (21.4%) underwent TUR, TUR+BCG, or TUR+chemotherapy, respectively. After a median follow-up period of 51.7 months (interquartile range=33.1-77.8 months), 286 patients (38.5%) developed tumor recurrence. The 5-yr recurrence rates for the TUR, chemotherapy, and BCG groups were 53.6%+/-2.7%, 30.8%+/-5.7%, and 33.6%+/-4.7%, respectively (P<0.001). Chemotherapy and BCG treatment were found to be predictors of reduced recurrence. Cox-regression analysis showed that TUR+BCG did not differ from TUR+chemotherapy in terms of recurrence risk. Adjuvant intravesical instillation is an effective prophylactic that prevents tumor recurrence in intermediate-risk NMIBC patients following TUR. In addition, both chemotherapeutic agents and BCG demonstrate comparable efficacies for preventing recurrence.