Dermoscopy of Basal Cell Carcinoma

Overview / DefinitionBasal cell carcinoma (BCC) is the most common form of skin cancer, arising from the basal layer of the epidermis. It is primarily a result of prolonged exposure to ultraviolet (UV) radiation. Dermoscopy enhances the visualization of BCC, aiding in its early detection and differentiation from other skin lesions. EpidemiologyBasal cell carcinoma accounts for approximately 80% of all non-melanoma skin cancers. Its incidence is rising, particularly in populations with fair skin. Risk factors include: UV exposure: both natural sunlight and artificial sources. Skin type: individuals with Fitzpatrick skin types I and II are at higher risk. Age: more common in older adults, especially those over 50 years. Immunosuppression: individuals with compromised immune systems are at increased risk. Pathophysiology / MechanismBasal cell carcinoma originates from mutations in the basal keratinocytes of the epidermis, primarily due to DNA damage from UV radiation. Common mutations involve the PTCH1 gene in the Hedgehog signaling pathway, leading to uncontrolled cellular proliferation. This results in the characteristic nodular or ulcerative lesions seen clinically. Clinical PresentationClinically, BCC presents in various forms: Nodular BCC: appears as a pearly, dome-shaped papule with telangiectasia. Superficial BCC: presents as a pink or red scaly patch, often misdiagnosed as eczema. Ulcerative BCC: can appear as a non-healing ulcer with a raised border. Sclerosing BCC: presents as a scar-like area with poorly defined edges. Diagnosis / WorkupDermoscopy plays a pivotal role in the diagnosis of BCC. Key dermoscopic features include: Telangiectasia: visible small blood vessels on the surface. Peripheral white halo: a white border around the lesion. Shiny surface: a characteristic glossiness. Multiple colors: may show shades of white, pink, and brown. Leaf-like areas: resembling leaves or clover patterns. Histological examination remains the gold standard for diagnos