Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed adenocarcinoma of the colon that is unlikely to respond to
existing therapy and for which no curative therapy exists

- Measurable disease by MRI or CT scan

- Metastatic or unresectable disease

PATIENT CHARACTERISTICS:

Age:

- 18 and over

Performance status:

- Karnofsky 60-100%

Life expectancy:

- At least 2 months

Hematopoietic:

- WBC at least 2,000/mm^3

- Platelet count at least 50,000/mm^3

Hepatic:

- Bilirubin no greater than 2.5 mg/dL

- SGOT/SGPT no greater than 5 times upper limit of normal

- No hepatic failure

Renal:

- Creatinine no greater than 2.5 mg/dL

- No renal failure

Cardiovascular:

- No chronic heart failure

- No uncontrolled hypertension

Pulmonary:

- No serious lung disease, such as chronic obstructive pulmonary disease

Other:

- Not pregnant or nursing

- Fertile patients must use effective contraception during and for 4 weeks after study
participation

- No active infection

- No serious malabsorption syndromes

- No other serious concurrent disease

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- At least 4 weeks since prior immunotherapy and recovered

Chemotherapy:

- At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas) and recovered

Endocrine therapy:

- Concurrent corticosteroids allowed

Radiotherapy:

- At least 8 weeks since prior radiotherapy and recovered (patients with multiple
tumors may be admitted earlier)

Surgery:

- No prior extensive stomach or intestinal surgery

Other:

- Prior cytodifferentiating agent allowed

- No prior antineoplaston therapy

- No other concurrent anticancer therapy