DISEASE CHARACTERISTICS:

• Oral leukoplakia on clinical examination AND/OR
• More than one prior squamous cell carcinoma (SCC) of the head and neck and dysplasia on biopsy within the past 6 months
• Carcinoma in situ or new leukoplakia eligible provided treatment for a prior carcinoma was completed more than 9 months ago

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-2

Life expectancy

• At least 12 months

Hematopoietic

• Platelet count at least 100,000/mm^3
• Absolute neutrophil count greater than 1,500/mm^3
• No bleeding diathesis

Hepatic

• Bilirubin less than 1.5 times upper limit of normal (ULN)
• Transaminases less than 1.5 times ULN
• PT/PTT less than 1.5 times ULN
• No acute or chronic liver disease

Renal

• Creatinine less than 1.5 times ULN
• Urine protein less than 2+
• No acute or chronic renal insufficiency

Cardiovascular

• No New York Heart Association class II congestive heart failure
• No prior myocardial infarction
• No angina
• No known coronary artery disease

Pulmonary

• No advanced chronic obstructive pulmonary disease requiring home oxygen use

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No infection within the past 2 weeks
• No concurrent infection

• No concurrent tobacco use (e.g., cigarette, cigar, pipe, or chewing tobacco)

  • At least 1 month since prior use
• No active alcohol abuse
• No history of gastrointestinal ulcer
• No history of anaphylactoid reaction to aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) or cyclo-oxygenase-2 (COX-2) inhibitors
• No concurrent active malignancy except non-melanoma skin cancer
• No contraindication to nasopharyngoscopy and biopsy

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No concurrent biologic therapy

Chemotherapy

• No concurrent chemotherapy

Endocrine therapy

• More than 3 months since prior absorbed steroids, including inhaled and nasal steroids (3 times a week for at least 2 consecutive weeks)

  • Prior mometasone allowed

Radiotherapy

• No concurrent radiotherapy

Surgery

• Prior surgery for SCC of the head and neck allowed provided patient has been cancer free for at least 9 months

Other

• More than 3 months since prior full-dose aspirin, COX-2 inhibitors, or NSAIDs (at least 3 times a week for at least 2 weeks)
• More than 3 months since prior retinoids or selenium
• No concurrent lithium or fluconazole
• No concurrent diuretics for congestive heart failure
• No concurrent angiotensin-converting enzyme inhibitors
• Concurrent aspirin allowed if dosage no greater than 81 mg per day