Within 2 weeks: topical medications, e.g. corticosteroids, alpha-hydroxyacids (glycolic acid, lactic acid) or retinoids (Retin-A) to the target lesions Within 4 weeks: systemic steroid therapy. Within 2 months: cryotherapy to the target lesions, laser resurfacing, chemical peels, topical application of 5-fluorouracil (5-FU) or masoprocol (Actinex) for treatment of actinic keratoses. Systemic treatment with chemotherapeutic agents, psoralens, immunotherapy, retinoids (Tegison, Accutane).