Evolution of intravesical immunotherapy for bladder cancer: mycobacterial cell wall preparation as a promising agent.

BACKGROUND

The intra-cavitary administration of antineoplastic agents for the treatment of non-invasive bladder cancer has met with variable results. Mytomicin-C [corrected] is effective in the prevention of tumor recurrence when administered in the immediate post-resection period, but also exhibits activity against papillary tumors. It lacks efficacy in carcinoma in-situ (CIS) of the bladder. Bacillus Calmette-Guérin (BCG) has been shown to be effective against papillary tumors, but particularly in the treatment of CIS. Unfortunately, live BCG has serious safety limitations.

OBJECTIVE

To review the current situation with the use of non-viable preparations of mycobacteria (M. phlei) that have been investigated for the treatment of superficial bladder cancer in limited open-label clinical trials.

CONCLUSION

MCC (Urocidin) [corrected] has shown activity against a variety of tumor cells, both in vitro and in animal cancer models. Limited clinical trials have also shown it to be active against non-muscle invasive bladder tumors in patients who have previously failed one or more courses of chemotherapy and/or immunotherapy with BCG. An unique dual immunomodulatory and apoptotic mechanism of action has been proposed for MCC.