Clinical study of prognostic factors of superficial bladder cancer treated with intravesical bacillus Calmette-Guerin.

Intravesical instillation of Tokyo 172 strain Bacillus Calmette-Guérin (BCG) was performed in 96 patients with initial superficial bladder cancer (Ta and T1) after transurethral resection (TUR) of tumour as a prophylaxis against tumour recurrence. The recurrence rate of tumours was estimated by the person-years method, comparing it with that of historical controls. There were statistically significant decreases in recurrent tumours following BCG therapy. To clarify the efficacy of intravesical BCG therapy, the prognostic significance of several factors was evaluated in patients with bladder cancer treated with TUR and instillation of BCG. The prophylactic effects were statistically better for those with multiple tumours, grade 3 lesions or Ta lesions than for control patients. No correlation between purified protein derivative (PPD) responsiveness and favourable results could be observed. Our results suggest that intravesical BCG instillation can alter the biological behaviour that affects the recurrence of superficial bladder cancer, especially for multiple, high grade or Ta tumours.