DISEASE CHARACTERISTICS:

• Diagnosis of familial adenomatous polyposis (FAP) of the colorectum based on 1 of the following criteria:

  • More than 100 polyps

  • More than 10 polyps and under age 40 OR more than 25 polyps and over age 40

    • Must have characteristic family history (autosomal dominant pattern), including 1 of the following:

      • More than 100 polyps in a first-degree relative
      • More than 25 polyps in 2 relatives in 2 generations, including a first-degree family member
      • Genetic diagnosis in a relative
      • Genetic diagnosis by in vitro synthesized protein or similar assay
• No anticipated colectomy within 8 months after randomization

• Colonic and/or rectal segment endoscopy documenting 1 of the following:

  • 5 or more rectal polyps each at least 2 mm in diameter

  • 5 or more colon polyps each at least 2 mm in diameter, including 1 of the following:

    • 3 quantifiable colon polyps greater than 3 mm in diameter
    • 2 quantifiable colon polyps greater than 5 mm in diameter
• Duodenal polyps allowed

PATIENT CHARACTERISTICS:

Age:

• See Disease Characteristics
• 18 to 65

Performance status:

• Not specified

Life expectancy:

• Not specified

Cardiovascular

• No history of cardiovascular disease
• No uncontrolled hypertension
• No family history of premature coronary disease
• No uncontrolled hypercholesteremia

Endocrine

• No history of uncontrolled diabetes

Hematopoietic:

• No significant hematologic dysfunction
• WBC at least 3,000/mm^3
• Platelet count at least 100,000/mm^3
• Hemoglobin at least 10.0 g/dL
• CRP less than 3.0 mg/L
• No known or prior coagulopathy

Hepatic:

• No significant hepatic dysfunction
• Bilirubin no greater than 2 times upper limit of normal (ULN)
• SGOT and SGPT no greater than 1.5 times ULN
• Alkaline phosphatase no greater than 1.5 times ULN

Renal:

• No significant renal dysfunction
• Creatinine no greater than 1.5 times ULN

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

• No clinically significant hearing loss, defined as:

  • Hearing loss that affects everyday life or for which a hearing aid is required
• No prior hypersensitivity to cyclooxygenase-2 inhibitors, sulfonamides, NSAIDs, or salicylates
• No discrete gastric or duodenal ulcer greater than 5 mm within the past year except Helicobacter pylori-related peptic ulcer disease treated successfully with antibiotics (as documented by an endoscopy)
• No invasive malignancy within the past 5 years except stage I or II colon cancer or resected nonmelanomatous skin cancer
• No other significant medical or psychiatric problems that would preclude study participation
• No history of deep venous thrombosis, pulmonary embolism, systemic lupus erythematous, family history of protein S or C deficiencies, prior heparin-induced thrombocytopenia, Factor V Leiden deficiencies or high homocysteine levels

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• Not specified

Endocrine therapy:

• No chronic adrenocorticosteroids

Radiotherapy:

• No prior pelvic irradiation

Surgery:

• See Disease Characteristics
• At least 1 year since prior partial or complete colectomy

Other:

• At least 3 months since prior investigational agents
• At least 3 months since prior chronic non-steroidal anti-inflammatory drugs (NSAIDs) (e.g., aspirin or celecoxib)
• No other concurrent NSAIDs (e.g., aspirin, ibuprofen, or naproxen)
• No concurrent warfarin, fluconazole, or lithium