Bacillus Calmette-Guérin in the management of superficial bladder cancer

Abstract

Intravesical Bacillus Calmette-Guérin (BCG) is the mainstay of superficial bladder cancer treatment. We performed a literature search through Medline/Pubmed using key words 'Bacillus Calmette-Guérin', 'intravesical', 'bladder neoplasm' and 'immunotherapy' for published data in the English language from 1970 to 2007 to review the current status of intravesical therapy and practice recommendations. The exact mechanism of action of intravesical BCG is yet to be elucidated. However, it appears that it is mediated by the local immune response, mainly through T-helper cell response. It reduces the recurrence rate by an average of 40% and progression by more than 20% in papillary tumors over the patients without BCG therapy. However, progression prevention is seen only in series which have used maintenance therapy at least for one year. It is effective in CIS of bladder with a response rate of more than 40% and prevention of progression in one-fourth patients. Most acceptable dose, induction treatment and maintenance therapy protocols are discussed. However, these are yet to be confirmed in large randomized trials. Intravesical BCG is well tolerated in most of the patients with mild to moderate side-effects in induction therapy; however, most patients do not complete maintenance therapy due to side-effects which is the most common concern at the present time.

Keywords: Bacillus Calmette-Guérin; bladder neoplasm; immunotherapy.