Actinic Keratosis

Synonyms

Solar keratosis.

Epidemiology

Dependent of skin type and life conditions. Prevalence in UK 6% in female and 15% in male.

Definition

Carcinoma in situ caused by chronic UV light exposure.

Aetiology & Pathogenesis

Chronic UV exposure followed by mutations of keratinocytes. In addition human papilloma virus (HPV), chemicals, genetic predisposition, immunosuppression.

Signs & Symptoms

Circumscribed hyperkeratotic yellow-brownish papules or plaques, sometimes flat or atrophic

Localisation

Sun-exposed areas (scalp, face, back of hands, shins, forearms).

Classification

Grade 1 to 3

Laboratory & other workups

None

Dermatopathology

Hyperkeratosis, epidermal disarray, atypical keratinocytes, inflammatory infiltrate, actinic elastosis.

Course

Chronic over years.

Complications

Transition to squamous cell carcinoma possible.

Diagnosis

Clinical features, histology.

Differential diagnosis

Bowen’s disease, seborrhoeic keratoses.

Prevention & Therapy

Prevention: sun protection.

Treatment: physical methods (cryosurgery, curettage, photodynamic therapy), topical methods (5-fluorouracil or immune modifiers: imiquimod cream, diclofenac, ingenol mebutate).

Special