Reducing recurrence and costs in superficial bladder cancer: preclinical evaluation of osmotic cytolysis by distilled water vs. mitomycin.

Transurethral resection followed by instillation of chemotherapeutic agents such as mitomycin is considered as standard therapy in recurrent superficial bladder cancer. However, incidence of bladder cancer is increasing, and contrariwise resources to finance the health care systems are decreasing. Therefore, effective alternatives to expensive chemotherapeutics are necessary. Recurrence of bladder cancer after transurethral resection is mostly promoted by reimplantation of dissolved tumour cells which are therapeutical purpose of any intravesically instillated agent. Monolayer cultures of human RT112, RT4, T24 and TCC SUP bladder cancer cells were incubated and exposed to mitomycin or distilled water. Cell survival was determined by microculture tetrazolium assay. Distilled water led to significant cytolysis in all tumour cells. This effect was comparable to exposition to mitomycin. Distilled water and mitomycin have comparable in vitro effects in bladder cancer cells. These findings have to be substantiated by an animal model emphasising the aspect of larger tumour cell compounds or possible damage to healthy bladder tissue.