The dressings are then removed and the lesion is treated with light at a specified wavelength. Multiple treatment regimens using different photosensitizers, incubation times, light sources, and pretreatment regimens have been studied and suggest that longer incubation times lead to higher rates of lesion clearance. Photodynamic therapy is gaining in popularity. It has been found to have a 14% higher likelihood of achieving complete lesion clearance at 3 months compared to cryotherapy, and seems to result in superior cosmetic outcomes when compared to cryotherapy or 5-FU treatment. Photodynamic therapy can be particularly effective in treating areas with multiple AK lesions. Surgical techniques
Surgical excision: Excision should be reserved for cases when the AK is a thick, horny papule, or when deeper invasion is suspected and histopathologic diagnosis is necessary. It is a rarely utilized technique for AK treatment. Shave excision and curettage (sometimes followed by electrodesiccation when deemed appropriate by the physician): This technique is often used for treatment of AKs, and particularly for lesions appearing more similar to squamous cell carcinoma, or those that are unresponsive to other treatments. The surface of the lesion can be scraped away using a scalpel, or the base can be removed with a curette. Tissue can be evaluated histopathologically under the microscope, but specimens acquired using this technique are not often adequate to determine whether a lesion is invasive or intraepidermal. Dermabrasion: Dermabrasion is useful in the treatment of large areas with multiple AK lesions.
The Imiquimod 3.75% cream has been validated in a treatment regimen consisting of daily application to entire face and scalp for two 2-week treatment cycles, with a complete clearance rate of 36%.While the clearance rate observed with the Imiquimod 3.75% cream was lower than that observed with the 5% cream (36 and 50 percent, respectively), there are lower reported rates of adverse reactions with the 3.75% cream: 19% of individuals using Imiquimod 3.75% cream reported adverse reactions including local erythema, scabbing, and flaking at the application site, while nearly a third of individuals using the 5% cream reported the same types of reactions with Imiquimod treatment. However, it is ultimately difficult to compare the efficacy of the different strength creams directly, as current study data varies in methodology (e.g. duration and frequency of treatment, and amount of skin surface area covered). Ingenol mebutate gel
Ingenol mebutate is a newer treatment for AK used in Europe and the United States. It works in two ways, first by disrupting cell membranes and mitochondria resulting cell death, and then by inducing antibody-dependent cellular cytotoxicity to eliminate remaining tumor cells. A 3-day treatment course with the 0.015% gel is recommended for the scalp and face, while a 2-day treatment course with the 0.05% gel is recommended for the trunk and extremities. Treatment with the 0.015% gel was found to completely clear 57% of AK, while the 0.05% gel had a 34% clearance rate. Advantages of ingenol mebutate treatment include the short duration of therapy and a low recurrence rate.