Bladder Cancer

Dr. Lamm's review of bacillus Calmette-Guérin (BCG) in the treatment of carcinoma in situ (CIS) of the bladder reflects one of the largest personal experiences of any investigator worldwide, and he should be congratulated for being one of those most responsible for the improved quality of life of many people due to the widespread use of BCG in bladder cancer. It is clear that BCG therapy allows a majority of patients with CIS to avoid cystectomy, and that it prevents progression to muscle involvement in many high-risk patients with papillary tumors.

Lamm describes a success story in oncology that he helped create, namely, the favorable therapeutic effect of intravesical bacillus Calmette-Guérin (BCG) against carcinoma in situ (CIS) of the bladder. Virtually every study conducted over the past decade reports complete responses in 70% or more patients treated with BCG, which are often durable for years [1]. Such results have been documented empirically in prospective controlled trials without complete understanding of the mechanism of action of BCG or the optimal dose and treatment regimen. More importantly, not only may BCG eradicate CIS but also it may delay or prevent tumor progression and improve patient survival [2]. Conversely, patients failing to respond to an adequate trial of BCG therapy are at increased risk for disease progression and death from bladder cancer. We now realize that the natural history of CIS in the bladder has been significantly altered by intravesical BCG.

Prior to the advent of BCG immunotherapy, bladder carcinoma in situ often progressed to muscle invasion. Intravesical chemotherapy completely eradicates the disease in 50% of patients, but fewer than 20% remain disease free after 5 years. Complete responses have been reported in 70% or more of BCG treated patients, nearly two-thirds of which are durable.