Long-term follow-up of cytostatic intravesical instillation in patients with superficial bladder carcinoma. Is short-term, intensive instillation better than maintenance therapy?

OBJECTIVES: Comparisons of two 3-year protocols, one 20-week protocol of mitomycin C instillation and one 3-year protocol of doxorubicin instillation for the prevention of recurrent tumors and progression in patients whose superficial bladder tumors had been removed by transurethral resection. METHODS: A prospective, randomized parallel group multicenter trial was conducted. 419 patients were evaluated after a median follow-up of 57 months. Cox proportional hazards analysis was performed. RESULTS: An overall recurrence rate of 22.7% and an overall progression rate of 9.8% was found. For time to progression a significant overall treatment effect was detected dependent on the recurrence status before entry into the study (p = 0.0059). Pairwise comparisons showed the mitomycin protocol with short-term intensive (weekly) combined with long-term maintenance instillation to have a highly beneficial effect compared to long-term maintenance instillation only especially for patients entering the study with recurrent tumors (RR = 0.06, 95% CI: [0.008, 0.506]. CONCLUSION: These results show that intensive therapeutic instillation may have an advantage over less intensive, prophylactic regimens.

[Long-term results of intravesical prevention of recurrence with mitomycin C and adriamycin in patients with superficial bladder cancer]. / Langzeitergebnisse einer intravesikalen Rezidivprophylaxe mit Mitomycin C und Adriamycin bei Patienten mit oberflächlichem Harnblasenkarzinom.

In a prospective multicenter study, four protocols for administration of mitomycin C and Adriamycin by intravesical installation were evaluated for effectiveness in the prevention of recurrent tumours in patients whose superficial bladder tumours (TA and T1) had been removed by transurethral resection. The 3-year and short-term installation protocols were compared with each other and each with a combination of the two. Evaluation after a mean follow up of 62.5 months was possible in 333 patients: the overall recurrence rate was 20.7% and the overall progression rate, 9.3%. No statistically significant differences were found in frequency of tumour recurrence among three mitomycin regimens and an Adriamycin regimen, regardless of the risk groups. However, frequency of recurrence per time unit was much lower in the treatment group with short-term intensive (weekly) mitomycin instillation, which was due mainly to prevention of late recurrence.