DISEASE CHARACTERISTICS:

• Histologically proven recurrent superficial bladder cancer

  • Intermediate prognosis as defined by the following:

    • Recurrent, multiple Ta, T1 carcinoma
    • Multiple (1-7) tumors
    • Tumors resected previously must be histological grade G1 or G2 OR

• Previously treated superficial bladder cancer requiring followup cystoscopy

  • Recurrent disease diagnosed at surgery
• No tumor invasion into muscle or carcinoma in situ

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• WHO 0-2

Life expectancy:

• Not specified

Hematopoietic:

• WBC at least 3,500/mm3
• Platelet count at least 150,000/mm3

Hepatic:

• No clinically significant hepatic disease

Renal:

• Creatinine clearance greater than 60 mL/min

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception during and for 6 months after study
• No history of adrenal insufficiency
• No other malignancy within the past 5 years except adequately treated cone-biopsied carcinoma in situ of the cervix or nonmelanoma skin cancer
• No history of difficult catheterization
• No confusion or disorientation
• No other condition that would preclude study compliance

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No concurrent biologic therapy

Chemotherapy:

• No concurrent chemotherapy

Endocrine therapy:

• No concurrent corticosteroids

Radiotherapy:

• No prior radiotherapy to the bladder
• No concurrent radiotherapy

Surgery:

• See Disease Characteristics
• At least 4 weeks since prior major thoracic or abdominal surgery

Other:

• Recovered from prior therapy and stable for 4 weeks
• At least 6 weeks since prior intravesicular therapy
• No prior or concurrent investigational drugs
• No concurrent anticoagulants