Celecoxib in Preventing Skin Cancer in Patients With Actinic Keratoses

DISEASE CHARACTERISTICS: * Diagnosis of Fitzpatrick skin types I, II, or III * Sun-damaged skin with 10-40 actinic keratoses on the upper extremities (upper arms, forearms, and hands), neck, face, and scalp combined PATIENT CHARACTERISTICS: Age: * 18 and over Performance status: * Not specified Life expectancy: * Not specified Hematopoietic: * WBC at least 3,000/mm\^3 * Platelet count at least 125,000/mm\^3 * Hemoglobin at least lower limit of normal * No significant bleeding disorder Hepatic: * Bilirubin no greater than 1.5 times upper limit of normal (ULN) * AST and ALT no greater than 1.5 times ULN * No chronic or acute hepatic disorder Renal: * Creatinine no greater than 1.5 times ULN * BUN no greater than 1.5 times ULN * No chronic or acute renal disorder Gastrointestinal: * No history of or active inflammatory bowel disease * No active pancreatitis * Not diagnosed with esophageal, gastric, pyloric channel, or duodenal ulceration within the past 30 days Other: * No history of keloid formation * No known photosensitivity disorder * No history of hypersensitivity or adverse reaction to sulfonamides, COX-2 inhibitors, salicylates, or other NSAIDs * No other condition that would preclude study * No other medical or psychosocial condition that would preclude study * No other malignancy within the past 5 years except: * Carcinoma in situ of the cervix * Curatively excised nonmelanoma skin cancer * Stage 0 chronic lymphocytic leukemia * Any cancer for which the patient is currently without evidence of disease, has not been treated for tumor within the past 6 months, has no current or planned therapy, and has an expected disease-free survival of at least 5 years * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: Biologic therapy: * At least 30 days since prior systemic immunotherapy * No concurrent immunotherapy Chemotherapy: * At least 3 months since prior topical fluorouracil (5-FU) * At least 6 months since other prior topical chemotherapy * No concurrent topical chemotherapy, including 5-FU * No other concurrent chemotherapy Endocrine therapy: * At least 6 months since prior oral or IV corticosteroids for more than 2 consecutive weeks * At least 6 months since prior inhaled or nasal corticosteroids for more than 4 weeks duration * At least 14 days since prior topical corticosteroids * At least 30 days since prior nasal corticosteroids (except mometasone) * No concurrent oral or IV corticosteroids for more than 2 consecutive weeks during any 6 month period during study * No concurrent inhaled or nasal steroids (except mometasone) for more than 4 weeks during any 6 month period during study * No concurrent hormonal or steroidal therapy, including topical corticosteroids * Concurrent hormone replacement therapy (e.g., estrogen or thyroid hormone replacement) allowed Radiotherapy: * At least 6 months since prior local radiotherapy to areas being studied * At least 30 days since other prior radiotherapy * No concurrent radiotherapy, including local radiotherapy to areas being studied Surgery: * Not specified Other: * At least 30 days since prior cryotherapy to target lesions * At least 60 days since prior laser resurfacing, dermabrasion, or chemical peels * At least 30 days since prior investigational medication * At least 14 days since prior topical alphahydroxyacids (e.g., glycolic acid or lactic acid) or retinoids * At least 30 days since prior systemic psoralens or retinoids * At least 30 days since prior treatment for esophageal, gastric, pyloric channel, or duodenal ulcers * At least 30 days since prior aspirin (more than 100 mg/day), other nonsteroidal anti-inflammatory drugs (NSAIDs) or COX-2 inhibitors at a frequency of at least 3 times per week for more than 2 weeks (except cardioprotective doses of aspirin (no more than 100 mg/day) * No concurrent systemic psoralens or retinoids * No concurrent prescription or over-the-counter topical medications to areas being studied (e.g., vitamin A derivatives) * No concurrent cryotherapy to target lesions * No concurrent laser resurfacing, dermabrasion, or chemical peels * No other concurrent investigational medications * No concurrent fluconazole or lithium * No concurrent chronic NSAIDs or COX-2 inhibitors (at least 3 times per week for more than 2 consecutive weeks per year) * Concurrent cardioprotective doses of oral aspirin (100 mg per day or less) allowed * Concurrent moisturizer/emollient or sunscreen allowed