A randomized study of intravesical BCG therapy for superficial bladder cancer -The comparative study for low doses of BCG treatment-

INTERVENTION: A: After TURBT, administering 27mg/41mL of BCG‐connaught strain intravesically once a week, 6 times in total B: After TURBT, administering 13.5mg/40.5mL of BCG‐connaught strain intravesically once a week, 6 times in total C: TURBT alone CONDITION: Superficial bladder cancer (Ta or T1, Grade1‐2) PRIMARY OUTCOME: recurrence‐free survival SECONDARY OUTCOME: Relation between the incidence of fever (over 37 degrees C) and non‐recurrence rate; Adverse drug reactions INCLUSION CRITERIA: 1) Patients aged between 20 and 85 at the time of registration 2) Patients with Performance Status (P.S.) levels of 0 to 2 [ECOG (Zubrod) score] 3) Patients in whose case all the tumors were removed within 1 month before the first day of administration, and the urinary cytology following TURBT was negative for malignancy. 4) Of patients whose all tumors removed by the TURBT this time was histologically confirmed to be superficial transitional‐cell cancer, those who satisfy any of the following conditions. [Primary patients] Stage Ta or T1, G1‐2 [Recurrent patients] Stage Ta or T1, G1‐2 and the recurrence period between the previous TURBT and the present TURBT was 12 months or longer 5) Patients with no carry‐over effects of previous treatments. 6) Patients with sufficient function of the major organs 7) Written informed consent obtained