Actinic keratosis, also known as “AKs” or solar keratosis, is a pre-cancerous cutaneous lesion that is very common in patients with increased sun exposure. These are termed “pre-cancerous” due to their ability to progress into a squamous cell type carcinoma.
Actinic keratoses form due to the proliferation of atypical epidermal keratinocytes.
Fair skinned individuals have the highest risk for the development of AKs. This coupled with increased exposure to ultraviolet light, advanced age, and male sex, increases the risk for the development of AKs.
Actinic keratoses typically present as a single or multiple erythematous, scaly macule, or papules. They are generally located on highly sun exposed areas such as the scalp, face, neck, dorsal hands, and dorsal forearms. These lesions are usually near areas of sun damaged skin that may appear as spotty, hyperpigmented skin with xerosis. These lesions are generally not symptomatic but can become tender.
Diagnosis is usually clinical, but in more hypertrophic lesions, a biopsy may be necessary to rule out malignancy.
The differential includes squamous cell carcinoma, benign lichenoid keratoses, verruca, inflamed seborrheic keratosis, porokeratosis, and forms of eczema (psoriasis, seborrheic dermatitis).
Treatment of actinic keratosis is dependent on the location of the lesions, number of lesions, patient preferences, and cost. Treatment options include cryotherapy with liquid nitrogen for few lesions or hypertrophic lesions, as well as topical fluorouracil, imiquimod, or photodynamic therapy (PDT) for regional treatment of actinic keratoses. A combination of the above may be necessary for hypertrophic lesions.
Written by Sydnee Eck, PA