The management of superficial
bladder cancer has advanced significantly in recent years. Controlled clinical trials suggest the benefits of cytotoxic
chemotherapy apply primarily to well-differentiated tumours, are short-term and do not include a reduction in
disease progression. In contrast, intravesical bacillus Calmette-Guérin (BCG)
immunotherapy is effective in high-grade tumours, provides long-term protection from tumour recurrence and reduces
disease progression. Controlled clinical trials have consistently demonstrated that BCG provides superior protection from tumour recurrence compared with
thiotepa or
doxorubicin. In comparisons with
mitomycin C, only two of six studies found a significant advantage for BCG
therapy; both studies evaluating high-risk patients showed a significant reduction in tumour recurrence with BCG compared with
mitomycin C. Controlled trials have demonstrated that newer
chemotherapies and more intensive regimens are not superior to standard
thiotepa treatment. However, controlled comparisons of
immunotherapy suggest that BCG is superior to both
interferon and
keyhole-limpet haemocyanin. Comparative studies showing BCG to be superior to
chemotherapy and other
immunotherapies have employed what we now know to be suboptimal BCG regimens. Using three additional weekly
BCG (Connaught) treatments at 3 months, complete response in
carcinoma in situ is increased from 73 to 87%. In patients who are disease free, maintenance BCG using three weekly treatments at 6-month intervals improves long-term disease-free status in stage Ta and T1
bladder cancer from 50 to 83%. Such maintenance
therapy improves the excellent 86% survival obtained with a single 6-week course of BCG to 92% (p < 0.04).