Dermoscopy of Basal Cell Carcinoma Part 2: Dermoscopic Findings by Lesion Subtype, Location, Age of Onset, Size and Patient Phototype

Introduction: Basal cell carcinoma (BCC) is the most prevalent type of skin cancer worldwide. Despite its low metastatic potential, certain subtypes present an aggressive clinical course. Part II focuses on the different dermoscopic patterns observed in BCC, depending on the lesion subtype, its location on the body, the patient's age, the size of the tumor, and skin phototype. Methods: A search of the PubMed database was conducted for studies reporting dermoscopic findings in BCC across all body locations, histopathologic subtypes, tumor sizes, ages of onset and skin phototypes. Results: There are no dermoscopic features indicative of a particular BCC subtype. However, arborizing, truncated or glomerular vessels, shiny white lines, ulceration, white areas, absence of pink zones and large blue-gray ovoid nests suggest high-risk BCCs (morpheaform, micronodular, infiltrative, basosquamous). Pigmented features can occur in all BCC types, though increased pigmentation indicates less aggressive subtypes (nodular, superficial, fibroepithelioma of Pinkus, adenoid). BCCs most commonly develop on the head, typically presenting as nodular and non-pigmented tumors. Those on the nose, eyes and ears may be more aggressive and prone to recurrence. On the trunk, BCCs are usually superficial and pigmented. Lower limb lesions often show polymorphous vessels rather than arborizing ones, which makes the dermoscopic diagnosis challenging. Dermoscopy aids early detection, with larger tumors exhibiting more established features but no size-specific patterns. Aggressive subtypes display similar dermoscopic findings regardless of size. Conclusions: Dermoscopy is a valuable tool for the early detection of BCC, though no specific dermoscopic features can definitively identify subtypes. High-risk BCCs can be suspected when distinct vascular and structural patterns are present, particularly in lesions located on the face, especially around the nose, eyes and ears, while pigmented features may indicate less aggressive subtypes.