Maintenance therapy with intravesical bacillus Calmette-Guerin in patients with intermediate- or high-risk non-muscle-invasive bladder cancer.

OBJECTIVE

We investigated the efficacy, safety and an optimal schedule of maintenance therapy with intravesical instillation of Bacillus-Calmette Guérin in patients with non-muscle-invasive bladder cancer.

METHODS

We compared the oncological outcome and adverse events of maintenance Bacillus-Calmette Guérin therapy (n = 40) with control subjects (n = 64) of Bacillus-Calmette Guérin induction therapy. Maintenance therapy was scheduled to be administered in 3-week cycles at 6, 12, 18, 24 and 36 months after the induction therapy.

RESULTS

There was a significant difference in the 5-year recurrence-free survival rate between the maintenance and induction groups in all patients (72.4 vs. 62.0%; P = 0.019) and in patients with high recurrence risk (100.0 vs. 17.9%; P = 0.009). There was a significant difference in the 5-year progression-free survival rate between the maintenance and induction groups in patients with high progression risk (100.0 vs. 69.3%; P = 0.047). Maintenance Bacillus-Calmette Guérin instillations for a total of four times or more (recurrence-free survival: hazard ratio: 0.2, P = 0.039) or with a total dosage of >243 mg (recurrence-free survival: hazard ratio: 0.2, P = 0.041) after 6 months of induction therapy significantly improve tumor recurrence-free survival and progression-free survival. There were no significant differences between induction therapy and maintenance therapy in the frequency of all adverse drug reactions.

CONCLUSIONS

Bacillus-Calmette Guérin maintenance therapy was effective in preventing the recurrence and progression of high-risk non-muscle-invasive bladder cancer. Maintenance Bacillus-Calmette Guérin instillations for a total of four times or more or with a total dosage of >243 mg after 6 months of induction therapy are necessary to obtain the optimal effect as maintenance therapy.