We divided randomly into 3 groups 47 patients with recurrent superficial transitional cell carcinoma of the bladder: group 1-15 controls who underwent transurethral resection only, group 2-17 patients who underwent transurethral resection and bacillus Calmette-Guerin therapy, and group 3-15 patients treated by transurethral resection and maltose tetrapalmitate. Mean followup was 22.93 months for the controls, 28.0 months for group 2 and 24.4 months for group 3. The recurrence rate per 100 patient-months was 11.34 in the controls, 7.4 in group 2 and 7.19 in group 3, and the recurrence index per month was 0.113, 0.070 and 0.072, respectively. The recurrence rate and recurrence index per month were significantly decreased in the treated groups compared to the controls (p less than 0.005). There was no significant difference between the bacillus Calmette-Guerin and maltose tetrapalmitate groups. Invasive carcinoma developed in 60 per cent of the controls, 29.4 per cent of group 2 and 20 per cent of group 3. Invasive carcinoma required cystectomy or definitive radiotherapy. Bacillus Calmette-Guerin caused irritation of the bladder mucosa, while maltose tetrapalmitate did not have any side effects.