RATIONALE: Green tea extract contains ingredients that may inhibit the growth of actinic keratosis.

PURPOSE: Randomized phase II trial to determine the effectiveness of green tea extract in treating patients who have actinic keratosis.

OBJECTIVES: I. Determine the efficacy of the green tea extract epigallocatechin gallate (Polyphenon E topical ointment) in causing complete clinical and histopathologic regression in patients with actinic keratoses. II. Determine duration of treatment with Polyphenon E necessary to cause regression in these patients. III. Describe pathophysiologic and molecular alterations in actinic keratoses and sun damaged skin that are not present in skin that is not sun damaged in these patients. IV. Determine the effects of this treatment on biomarkers for skin cancer in these patients.

OUTLINE: This is a randomized, double blind, placebo controlled study. One of the patient's arms is randomized to receive topical epigallocatechin gallate (Polyphenon E), the other arm to receive a placebo. Patients receive topical applications daily for 12 weeks, or until resolution of all actinic keratoses within the treatment field.

PROJECTED ACCRUAL: A minimum of 60 patients will be accrued for this study over 10 months.

DISEASE CHARACTERISTICS: Clinically and histologically confirmed grade 1-3 actinic keratoses At least 2 actinic keratoses on each arm

PATIENT CHARACTERISTICS: Age: Over 18 Performance status: SWOG 0-1 Karnofsky 70-100% Life expectancy: Not specified Hematopoietic: Not specified Hepatic: Not specified Renal: Not specified Other: No prior invasive malignancy within past 5 years except nonmelanomatous skin cancer, stage I carcinoma in situ of the cervix, or stage 0 chronic lymphocytic leukemia No severe metabolic disorder No life threatening acute or chronic disease No medical condition that would preclude study No active systemic infectious disease that may affect immune system No prior keloid formation Not pregnant or nursing Negative pregnancy test

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 2 months since prior immunotherapy Chemotherapy: At least 2 months since prior topical application of fluorouracil or masoprocol for actinic keratoses At least 2 months since prior systemic chemotherapy No further anticipated chemotherapy Endocrine therapy: At least 2 weeks since prior topical corticosteroids to target lesions At least 4 weeks since prior systemic steroid therapy Radiotherapy: No anticipated radiotherapy Surgery: Not specified Other: At least 2 weeks since prior other topical medications (e.g., retinoids or alpha hydroxyacids such as glycolic acid or lactic acid) At least 2 months since prior cryotherapy to target lesions At least 2 months since prior systemic psoralens or retinoids At least 2 months since prior laser resurfacing or chemical peels At least 30 days since prior other investigational drug No other concurrent topical medication to areas being studied