Fenretinide in Treating Patients Who Have Undergone Surgery for Bladder Cancer

DISEASE CHARACTERISTICS: * Histologically proven solitary or multifocal superficial (stage Ta, grades 1-2) transitional cell carcinoma (TCC) of the bladder meeting 1 of the following criteria: * Newly diagnosed and no more than 4 weeks since resection * Secondary after being tumor free (including carcinoma in situ) for more than 12 months with no intravesical therapy within that 12 months OR * Histologically proven Ta, T1, or Tis TCC of the bladder previously treated with Bacillus Calmette-Guerin (BCG). * Must have received 6 weeks of induction BCG followed by no evidence of disease by cystoscopy and cytology and then further treatment with 3 weekly doses of BCG. * Visible tumor totally resected within 4 weeks prior to study entry and no further surgery, intravesical therapy, or systemic therapy planned * No prostatic, prostatic urethral, or upper tract TCC involvement by the index tumor at resection * No metastatic disease PATIENT CHARACTERISTICS: Age: * 18 and over Performance status: * Zubrod (Eastern Cooperative Oncology Group (ECOG)) 0-2 Life expectancy: * At least 2 years Hematopoietic: * white blood count (WBC) greater than 3,000/mm\^3 * Platelet count greater than 100,000/mm\^3 * Hemoglobin greater than 11.0 g/dL Hepatic: * serum glutamic oxaloacetic transaminase (SGOT) or serum glutamic pyruvic transaminase (SGPT) less than 1.5 times upper limit of normal (ULN) Renal: * Creatinine less than 2.0 mg/dL Other: * Triglyceride level less than 2.5 times ULN * No other concurrent malignancy except nonmelanomatous skin cancer * No other malignancy within the past 5 years unless currently disease free, at least 6 months since prior therapy, no current or planned active therapy, and expected disease-free survival at least 2 years * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception during and for 1 year after the study participation PRIOR CONCURRENT THERAPY: Biologic therapy: * See Disease Characteristics * No concurrent systemic biologic therapy Chemotherapy: * See Disease Characteristics * No prior systemic cytotoxic chemotherapy for bladder cancer * At least 1 year since prior cytotoxic chemotherapy for nonbladder cancer * No concurrent systemic chemotherapy Endocrine therapy: * Not specified Radiotherapy: * No prior radiotherapy to the bladder * No concurrent radiotherapy Surgery: * See Disease Characteristics Other: * At least 3 months since prior high-dose vitamin A (greater than 25,000 IU) or beta carotene (at least 30 mg/day) * At least 3 months since prior retinoid therapy