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.
Cause
Actinic keratoses form due to the proliferation of atypical epidermal keratinocytes.
Risk Factors
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.
Presentation
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
Diagnosis is usually clinical, but in more hypertrophic lesions, a biopsy may be necessary to rule out malignancy.
Differential Diagnosis
The differential includes squamous cell carcinoma, benign lichenoid keratoses, verruca, inflamed seborrheic keratosis, porokeratosis, and forms of eczema (psoriasis, seborrheic dermatitis).
Treatment
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