[Intravesical instillation of bacillus Calmette-Guerin for superficial bladder carcinoma: study on significance of additional maintenance instillations of bacillus Calmette-Guerin].

The efficacy of maintenance bacillus Calmette-Guerin (BCG) instillations for superficial bladder tumors was studied by prospective randomized trial. From June 1985 to October 1988, 42 newly diagnosed patients with superficial bladder carcinoma (pTa or pT1) were treated by transurethral tumor resection and subsequent five daily instillations of mitomycin C. Then they were divided into non-maintenance group (22 patients) and maintenance group (20 patients) by randomization. The patients received six weekly instillations of 80 mg of BCG. Tokyo strain (Japan BCG manufacturing Co., Tokyo, Japan), suspended in 40 ml of physiological saline, and the patients in the maintenance group received four additional instillations of BCG every three months. We could not complete the six-week course of BCG instillations in three patients due to adverse effects (two in non-maintenance group and one in maintenance group) and we lost six patients from follow-up within one year (one in non-maintenance group and five in maintenance group). The mean follow-up period of the remaining 33 patients was 28.1 months. Of these 33 patients, six patients had been found to have recurrent tumors, and the over-all three-year non-recurrence rate was 82%. Before employing BCG, when we used only mitomycin C after TUR-Bt, the three year non-recurrence rate was 58%. This indicates prophylactic effect of BCG instillations. The stage of the initial tumor of the six recurrent cases were all pT1b. The non-recurrence rate of the patients with pT1b tumor was significantly lower than that of the patients with pTa and pT1a tumor. However, multiplicity and grade of tumors did not affect the non-recurrence rate.(ABSTRACT TRUNCATED AT 250 WORDS)