Efficacy and tolerance of one-third full dose bacillus Calmette-Guérin maintenance therapy every 3 months or 6 months: two-year results of URO-BCG-4 multicenter study.

OBJECTIVES

To assess bacillus Calmette-Guérin maintenance treatment schedule for non-muscle invasive bladder cancer at 2 years, using one-third of the full dose and fewer instillations every 3 months or 6 months.

METHODS

This was a prospective, randomized, multicenter study. All patients had an intermediate- or high-risk non-muscle invasive bladder cancer. They received three weekly instillations of one-third dose bacillus Calmette-Guérin every 6 months (group I) and two weekly instillations every 3 months (group II) during 3 years. In the two schedules we assessed efficacy, tolerance, leukocyturia and prostate-specific antigen.

RESULTS

No significant difference was observed between the two groups for recurrence at 6, 12 or 18 months. At 2 years, tumor recurrence was observed in 10.9% and muscle invasion in 2.9% of cases. Bacillus Calmette-Guérin tolerance was comparable - the adverse events score was 0.8 in group I and 1 in group II (P = 0.242). No statistical correlation was observed between the adverse events score over 2 years, either for leukocyturia (P = 0.8891) or prostate-specific antigen level (P = 0.7155). Leukocyturia level was not significantly associated with tumor recurrence or progression.

CONCLUSION

One-third dose maintenance bacillus Calmette-Guérin is effective with no impact on tumor recurrence or muscle invasion. Furthermore, there seems to be no difference in tumor response or side-effects between patients receiving two or three maintenance instillations every 3 months or 6 months. In clinical practice, the use of leukocyturia or total prostate-specific antigen levels do not appear to be useful in predicting bacillus Calmette-Guérin toxicity.