Inclusion Criteria

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