RESUMEN
BACKGROUND/AIM: This study aimed to compare the clinical efficacy of two different Bacillus Calmette-Guérin (BCG) strains, TICE strain (OncoTICE) and Connaught strain (ImmuCyst), as a first line intravesical instillation therapy in patients with T1 high grade bladder cancer. PATIENTS AND METHODS: Patients with newly diagnosed T1 high-grade bladder cancer who underwent transurethral resection of bladder tumor (TURBT) followed by intravesical instillation therapy were enrolled. The effects of BCG strain on recurrence, progression, and side effects were analyzed using Kaplan-Meier and Cox proportional hazards models. RESULTS: Among 147 patients, 53 patients received Connaught strain and 94 patients received TICE strain. The completion rate of induction instillation was 92.45% in the Connaught group and 91.49% in the TICE group (p=1.00). The three-year recurrence-free survival rate was 71.7% in the Connaught group and 63.83% in the TICE group (p=0.33), whereas the three-year progression-free survival rate was 96.23% in the Connaught group and 89.36% in the TICE group (p=0.21). On Cox regression test, carcinoma in situ and ≥eight lesions were significant predictors for recurrence. No significant difference was observed in recurrence and progression between the two BCG regimens. The complication rates according to the Cleveland Clinic grading system showed no significant difference between the two groups (p=0.13). CONCLUSION: Both the Connaught and TICE strains of BCG demonstrated comparable three-year recurrence-free survival rates and three-year progression-free survival rates for T1 high grade bladder cancer, as well as comparable adverse events. Due to the global BCG shortage, further strain comparisons are essential for clinical validation.