Inclusion Criteria

DISEASE CHARACTERISTICS:

- Metastatic lesions to the brain

- Must not require immediate radiotherapy

- If received prior radiotherapy, must have progressive disease

- Evaluable disease by CT scan or MRI

- Neurologically stable

PATIENT CHARACTERISTICS:

Age:

- 18 and over

Performance status:

- Karnofsky 70-100%

Life expectancy:

- More than 12 weeks

Hematopoietic:

- Absolute neutrophil count at least 1,500/mm^3

- Platelet count at least 100,000/mm^3

- Hemoglobin at least 10 g/dL

Hepatic:

- Bilirubin less than 1.5 times upper limit of normal (ULN)

- SGOT or SGPT less than 2.5 times ULN

- Alkaline phosphatase less than 2 times ULN

Renal:

- Blood urea nitrogen less than 1.5 times ULN

- Creatinine less than 1.5 times ULN

Other:

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No other concurrent nonmalignant systemic disease

- No acute infection requiring treatment with IV antibiotics

- HIV negative

- No frequent vomiting or medical condition that would preclude oral medication
administration (e.g., partial bowel obstruction, inability to swallow)

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- No concurrent hematopoietic growth factors, including epoetin alfa

- No other concurrent biologic therapy

Chemotherapy:

- At least 4 weeks since prior chemotherapy, unless evidence of disease progression

- No other concurrent chemotherapy

Endocrine therapy:

- Concurrent corticosteroids allowed if nonincreasing dose for at least 1 week prior to
study

Radiotherapy:

- See Disease Characteristics

- At least 4 weeks since prior radiotherapy to the brain, unless evidence of disease
progression

- No concurrent radiotherapy

Surgery:

- At least 3 weeks since prior surgery, unless evidence of disease progression, and
recovered

Other:

- No other concurrent investigational drugs