Dermatoscopia del carcinoma basocelular: diagnóstico precoz, detección de recidiva e identificación de subtipos histológicos

Dermoscopy or epiluminescence microscopy, is a non-invasive, in vivo, diagnostic technique to visualize morphological structures as pigment and vessels not detectable by the naked eye. It thus becomes the bridge between the macroscopic clinical examination and pathological analysis. Dermoscopy could possibly help to identify very early tumor lesions or recurrence at an early stage, allowing early treatment. It may optimize the diagnostic and therapeutic processes by histologic subtype of basal cell carcinoma, all of which lead to a reduction in morbidity and mortality for patients as well as a reduction in healthcare costs. Polarized contact dermocopy is used. Images are evaluated by two blinded dermatologists. GOALS: Primary objective: to describe the dermoscopic findings in small basal cell carcinoma (≤5mm) and recurrent basal cell carcinoma. Secondary Objectives: to study the association between dermoscopic structures of basal cell carcinoma according to histological subtype of tumor. RESULTS 1. The most common dermoscopic structure in basal cell carcinoma (BCC) is arborizing telangiectasias (43.49%) and ulceration (41.55%). 2. Recurrent basal cell carcinoma is characterized by linear irregular vessels (OR 13.04). There are no significant differences in other dermatoscopic structures in relation to recurrence. 3. Small basal cell carcinoma (≤5mm) can present the vast majority of dermoscopic structures that can be observed in bigger basal cell carcinomas. Arborizing telangiectasia and ulceration appear more frequently in tumors> 5 mm. 4. No dermoscopic structure is specific for any histological subtype of basal cell carcinoma, but their frequency differs between the different subtypes of basal cell carcinom. Basal cell carcinoma histologic subtypes are characterized by the following dermoscopic features: a. Nodular (solid) basal cell carcinomas more often display large blue-gray nests (OR 2.42), but no shiny white to red areas or multiple superficial erosions are frequently seen (OR 0.34 and 0.07) . b. Superficial basal cell carcinoma shows multiple superficial erosions (OR 18.76), pigment network and maple leaf-like áreas (OR 3.42). There is a negative relationship between superficial basal cell carcinoma, arborizing telangiectasia (OR 0.14) and white shiniy áreas (OR 0.12). c. Infiltrating basal cell carcinoma rarely shows multiple in focus blue-gray dots (OR 0.19). d. Sclerosing (morpheiphorm) basal cell carcinoma frequently shows ulceration (OR 4.62), and rarely maple leaf-like áreas (0.06). e. Basosquamous carcinoma is characterized by lower presence of semitraslucency (OR 0.08) or multiple blue-gray globules (OR 0.12). This histologic subtype has the lowest prevalence of pigmented structures. 5. All pigment structures are more common in any of the histological subtypes with a good prognosis (solid/nodular, superficial, follicular) than in any of the subtypes of poor prognosis (basosquamous, sclerosing, infiltrating, micronodular). Ulceration is more common in histological subtypes of poor prognosis respect to good prognosis. 6. The interobserver correlation is highly variable for different dermoscopic structures. The correlation has been excellent (kappa>0.80) in the classification of ulceration and blue-white veil. It has been very good (kappa 0.61-0.80)in the pigmented structures (cells, nests and blue-gray dots, concentric structures, spoke-wheel and maple leaf areas). However it has been good, moderate or poor (kappa ≤0.60) for the vast majority of vascular structures and shiny white structures.