Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histopathologically confirmed non-muscle-invasive transitional cell carcinoma (TCC)
of the bladder (< pT2 ), meeting any of the following criteria:

- Solitary grade 1, pTa (≥ 3 cm) tumor

- Any other pTa, pTis (carcinoma in situ), or pT1 tumor

- Newly diagnosed disease

- Meets 1 of the following risk criteria for recurrence:

- Intermediate-risk disease

- Multiple grade 1, pTa (> 1) tumor

- Solitary grade 1, pTa (≥ 3 cm) tumor

- Grade 2, pTa tumor

- Grade 1, pT1 tumor

- Grade 2, pT1 (1 or 2 tumors)

- High-risk disease

- Grade 3, pTa tumor

- Grade 3, pT1 tumor

- Tis (carcinoma in situ)

- Multiple grade 2, pT1 (≥ 3 foci) tumor

- Has undergone diagnostic transurethral resection of the bladder tumor/biopsy within
the past 3 months

- No residual tumor, defined as a recurrence within 3 months after initial
treatment (due to incomplete resection of the primary index tumor or
implantation after biopsy)

- No prostatic, prostatic urethral, or upper tract TCC involvement by the index
tumor at resection

- No muscle invasion or advanced disease

- No metastatic disease

PATIENT CHARACTERISTICS:

- Able to swallow pills

- Not pregnant

- Fertile patients must use effective contraception

- No other malignancy within the past 5 years

- No known hypersensitivity or adverse reactions to selenium

- No other serious medical or psychiatric illness that would preclude giving informed
consent

- No condition that, in the opinion of the investigator, may interfere with the safety
of the patient or the evaluation of the study objectives

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- More than 30 days since prior daily dietary supplements containing selenium

- No other concurrent selenium (contained in individual supplements, antioxidant mix,
or multivitamin) intake

- No concurrent participation in another study involving a medical, surgical,
nutritional, or lifestyle intervention

- Concurrent participation in the follow-up phase of another study allowed