Alternating mitomycin C and bacillus Calmette-Guerin instillation therapy for carcinoma in situ of the bladder. The Finnbladder Group.

Our aim was to prove if alternating chemotherapeutic and immunotherapeutic instillations improved efficacy and reduced toxicity in patients with carcinoma in situ of the bladder.Of 68 carcinoma in situ patients randomly treated with instillations 40 received mitomycin C and 28 received mitomycin C and Pasteur bacillus Calmette-Guerin (BCG) in alternating courses. Mean followup was 33 months.The complete response rates with mitomycin C and mitomycin C/BCG were 45% and 71% at 3 months, 59% and 82% at 12 months, and 47% and 74% at 24 months, respectively (p = 0.041). The disease-free interval showed the superiority of alternating therapy (p = 0.043). Recurrence rates during the instillation period were 1.834 with mitomycin C and 0.922 with mitomycin C/BCG (p = 0.013). No remarkable side effects developed in the alternating group.Therapy of carcinoma in situ with alternating mitomycin C and BCG is more effective than mitomycin C alone. Compared to BCG monotherapy only few side effects occur.