Inclusion Criteria

DISEASE CHARACTERISTICS:

- One of the following must be present:

- At least 1 positive fecal occult blood test within the past 6 months

- Iron deficiency anemia, defined as:

- Hemoglobin less than 13 g/dL (males)

- Hemoglobin less than 12 g/dL (females)

- Ferritin less than 45 g/dL

- Episode of bright red blood per the rectum

- Family history of colon cancer or adenoma

- One first-degree relative diagnosed with colon cancer or adenoma at age 60
or under OR

- Two first-degree relatives diagnosed with colon cancer or adenoma at any
age

- No active gastrointestinal hemorrhage, including any of the following:

- Reported or witnessed hematemesis

- Melenic stools

- Melenemesis

- Multiple episodes of hematochezia within the past 2 months

PATIENT CHARACTERISTICS:

Age:

- 18 and over

Performance status:

- Not specified

Life expectancy:

- Not specified

Hematopoietic:

- See Disease Characteristics

Hepatic:

- Not specified

Renal:

- Not specified

Cardiovascular:

- No myocardial infarction or cerebrovascular accident within the past 6 weeks

Pulmonary:

- No respiratory failure within the past 6 weeks

Other:

- No serious medical disorder (e.g., sepsis) within the past 6 weeks

- Weight less than 300 pounds

- Willing and able to undergo endoscopic or radiologic procedures

- No need for special precautions in performing endoscopic procedures (e.g.,
antibiotic prophylaxis or complicated anticoagulation reversal)

- No prisoners

- Not pregnant

- Negative pregnancy test

- Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- Not specified

Chemotherapy:

- Not specified

Endocrine therapy:

- Not specified

Radiotherapy:

- Not specified

Surgery:

- Not specified

Other:

- No other concurrent clinical trial participation involving drugs, medical devices,
and/or biologics