Risk stratification of basal cell carcinoma by dermoscopy: dermoscopic predictors from a large retrospective study of 1,091 lesions

Abstract

Dermoscopy is a key tool for diagnosing basal cell carcinoma (BCC). While numerous dermoscopic features have been associated with specific histopathological subtypes, most studies are limited by relatively small sample sizes, particularly regarding aggressive variants. Consequently, robust large-scale data evaluating dermoscopic predictors of high-risk histopathology remain insufficient. To comprehensively characterize dermoscopic features across BCC subtypes in a large cohort and to identify independent dermoscopic predictors of high-risk histopathology. We retrospectively analyzed 1,091 histopathologically confirmed BCCs from 690 patients treated at Ankara University (2016–2023). Lesions were assessed dermoscopically for vascular patterns, pigmentation, structureless areas, keratin, and ulceration. Lesions were categorized into low-risk (superficial, nodular, superficial-nodular) and high-risk (micronodular, infiltrative, basosquamous, nodular-micronodular mix) groups. Logistic regression identified independent dermoscopic predictors of high-risk histopathology. Ulceration, particularly involving >50% of the lesion surface, was the strongest predictor of high-risk histopathology (OR 9.436). Additional independent predictors included thick short and long serpentine vessels, isolated keratin, ulcer–keratin combinations, white calcified clods, white circles, and small black clods. In contrast, pigmented structures and short fine serpentine vessels were more frequent in low-risk lesions. Blue-gray structures were more frequently focused in low-risk lesions, whereas unfocused or mixed appearances predominated in high-risk lesions, reflecting deeper tumor nests. Dermoscopy provides valuable risk stratification information beyond diagnosis alone. Specific vascular, keratin-related, and white structural features may help identify high-risk BCC and guide biopsy site selection and treatment planning.