The use of bacillus Calmette-Guerin in the therapy of bladder carcinoma in situ.

Intravesical instillations of Tice strain bacillus Calmette-Guerin were given to 33 patients with biopsy proved carcinoma in situ. An induction phase consisting of 12 weekly instillations was followed by a maintenance phase of instillations bimonthly for 3 months and then monthly for 18 months. A total of 6 patients did not complete the induction phase because of adverse reactions but 4 were rendered free of tumor and have had no recurrence. Of the remaining 27 patients 18 became free of tumor after 12 weeks of therapy (3 had recurrences during the maintenance period), 6 after 18 weeks (with 1 recurrence) and 3 after 24 weeks. Thus, 31 of 33 patients (94 per cent) were rendered free of carcinoma in situ. There were 4 recurrences in these patients (13 per cent). The 27 patients who have remained free of disease have been followed for 1.75 to 8.5 years, with an average of 5.25 years. Side effects, principally bladder irritability, were a problem early in the study. With the use of isoniazid, nonsteroidal anti-inflammatory agents and bladder antispasmodics, the treatment has been safe and tolerated well. The study indicates that bacillus Calmette-Guerin is effective in eliminating carcinoma in situ in most patients, although prolonged treatment may be necessary. Maintenance therapy appears to be of value in reducing the incidence of recurrent tumor.