Abstract
INTRODUCTION: Basal cell carcinoma (BCC) is the most common malignant skin tumor. While rarely fatal, it can cause local tissue damage. Part I of the review summarizes the dermoscopic features of BCC and the diagnostic accuracy of dermoscopy in the diagnosis of BCC. METHODS: A search of the PubMed database was performed for studies reporting on the diagnostic accuracy of dermoscopy or dermoscopic findings in BCC, either pigmented or non-pigmented, located anywhere on the body, of any histopathologic subtype, size and at any age of onset. RESULTS: BCC was found to present with a wide range of dermoscopic features, including white structures (shiny white lines, shiny white areas, rosettes), yellow structures (milia-like cysts, yellow lobular-like structures), multiple aggregated yellow-white globules (MAY globules), blue structures (blue ovoid nests), vascular structures (arborizing vessels, short fine telangiectasias), multiple small erosions/ulcerations, features of regression (pepper-like structures, white scar-like areas) and pigmented structures (spoke-wheel areas, maple leaf-like areas (MLLAs), blue/gray dots). Dermoscopy showed a sensitivity of 67.6-98.6% and a positive predictive value (PPV) of 85.9-97% in identifying BCC. The physician's experience and training improve the accuracy, however, BCCs on the trunk and extremities, particularly of superficial subtypes, may still constitute a challenge. CONCLUSIONS: Dermoscopy, especially when performed by a trained physician, increases the accuracy of early BCC detection.