DISEASE CHARACTERISTICS:

Histologically confirmed superficial transitional cell carcinoma of the bladder pathologically staged as Tis, Ta, or T1. Visible tumors at time of treatment not required. No metastatic disease or muscle invasion.

Clinically useful pretreatment bladder function required.

No significant prostatic obstructive symptoms associated with impaired or incomplete bladder emptying.

No active urinary tract infection.

PRIOR/CONCURRENT THERAPY:

At least 1 course of prior standard intravesical therapy required.

At least 4 weeks since intravesical treatment, with resolution of any local or systemic toxicity.

PATIENT CHARACTERISTICS:

Age: 18 and over.

Performance status: ECOG 0 or 1.

Hematopoietic:

WBC at least 3,300;

Hemoglobin at least 10 g/dL.

Hepatic:

Bilirubin no greater than 1.5 mg/dL;

AST and ALT no greater than 2 times normal.

Renal: Creatinine no greater than 1.5 mg/dL.

OTHER:

Medically able to undergo cystoscopy.

No pregnant women.