dermatologic disorders
Actinic Keratoses
Treatment of Actinic Keratoses
Lesion-directed or field-directed therapy Treatment options depend on the number of lesions, their location, extent of photodamage, and patient preference, but typically they are divided into 2 categories: Lesion-directed therapy Field-directed therapy Inlesion-directed therapy,individual lesions are physically removed. This option may be better if the patient has only a few actinic keratoses, or if the patient is unable or unwilling to undergo other therapy options. Cryosurgery (freezing with liquid nitrogen) is the most common lesion-directed therapy. Curettage (scraping with a curette) is an alternative. Lesion-directed therapies have the benefit of being single, in-office procedures, but they may not address subclinical changes and have a higher risk of scarring. Infield-directed therapy,topical treatments are applied to larger, diffuse areas of involvement. Topicalfluorouracil(5-FU) cream andimiquimodcream are the usual first-line drug treatments. Alternatives includediclofenacgel andtirbanibulinointment. 5-FU inhibits thymidylate synthetase, limiting DNA synthesis and causing death of damaged cells. 5-FU 5% cream is applied 2 times a day for 3 to 4 weeks. A recent study has shown 5-FU to be the most effective treatment for actinic keratoses ( Treatment references ). Early data suggest that combining 5% FU cream with 0.005% calcipotriol may enhance efficacy of 5-FU ( Imiquimodis an immune response modifier that stimulates local cytokine induction, resulting in a brisk local inflammatory reaction.Imiquimod5% cream is applied 2 times a week for 16 consecutive weeks. Diclofenacis a nonsteroidal anti-inflammatory drug that inhibits both cyclooxygenase and upregulation of the arachidonic acid cascade.Diclofenac3% (in a 2.5% hyaluronan gel) is applied 2 times a day for 60 to 90 days. Its use is limited by its low efficacy. Tirbanibulinis a microtubule inhibitor that inhibits tubulin polymerization and Src kinase signaling, inducing death of damaged cells.Tirbanibulin1% ointment is applied once a day for 5 days; however, there are currently only short-term data on safety and efficacy available. These topical drugs can cause inflammation (often with redness and scaling) and pain during treatment and usually for 1 to 2 weeks afterward. Photodynamic therapy is another type of field-directed therapy. It involves topical application of a photosensitizer (eg, aminolevulinate,methyl aminolevulinate) followed by light of a specific wavelength that preferentially affects photodamaged skin. Like topical field-directed therapy, photodynamic therapy can cause redness and scaling during treatment. More than one treatment session may be needed. If patients do not respond to therapy, clinicians should consider doing a biopsy to rule out squamous cell carcinoma. Patients should also be told about the importance of Prevention . 1.Jansen M, Kessels J, Nelemans P, Kouloubis N, et al: Randomized trial of four treatment approaches for actinic keratosis.N Engl J Med380(10):935–946, 2019. doi: 10.1056/NEJMoa1811850 2.Cunningham TJ, Tabacchi M, Eliane JP, et al: Randomized trial of calcipotriol combined with 5-fluorouracilfor skin cancer precursor immunotherapy.J Clin Invest127(1):106–116, 2017. doi: 10.1172/JCI89820 