The current status of intravesical therapy for superficial bladder cancer

Abstract

To analyse recent advances in intravesical instillation therapy for superficial bladder cancer. Although intravesical bacillus Calmette-Guérin has been used for many years in the treatment of superficial bladder cancer, its mechanism of action remains unclear, its poor tolerance remains a problem, the prediction of its efficacy has still to be validated, and its long-term effects on progression and survival are controversial. The exact timing and place of intravesical chemotherapy needs to be better defined, as well as the place of some new molecules. Finally, new approaches need to be explored for overcoming the limitations of the usual intravesical agents. No dramatic advances have been made in understanding the mechanisms of action of bacillus Calmette-Guérin during the past year. However, a careful dissection of this complex immunological pathway continues and immunological criteria are promising for predicting the response to bacillus Calmette-Guérin. Evidence has been accumulating to suggest that a dose reduction during the initial treatment remains effective and reduces side-effects. In addition, bacillus Calmette-Guérin maintenance therapy is useful for high-risk patients. However, long-term tolerance remains an important issue, and the optimal protocol has not yet been defined. On the other hand, it has been proved that intravesical chemotherapy, when administered early after transurethral resection, is effective in preventing frequent recurrences, whereas maintenance chemotherapy is ineffective. Finally, new approaches, including instillations of activated immune cells or targeted gene therapy, are being explored.