Comparative Dermoscopic Analysis of Melanoma In Situ Versus Thin Invasive Melanoma Considering BRAF Mutational Status

Background/Objectives: BRAF mutation is the most frequent somatic mutation in melanoma. The BRAF mutational status is crucial in selecting systemic therapy for advanced melanoma. Another important consideration is whether a melanoma is in situ or invasive. If this aspect could be known before the first surgical intervention, the appropriate surgical margins could be chosen from the beginning and a second surgical step could be avoided. Could the dermoscopic image predict the BRAF mutational status? Could it also predict if a melanoma is in situ or invasive? Methods: This retrospective study included 50 patients with 52 melanomas. The mutational status of the BRAF gene was determined, and the dermoscopic images were analysed. Results: There were no statistically significant differences between the BRAF-mutant melanoma group and the BRAF wild-type melanoma group. However, there were statistically significant differences between the dermoscopic images of melanomas in situ and thin invasive melanomas (≤1 mm Breslow thickness). Irregular dots or globules (p = 0.008), a blue-white veil (p = 0.011), milky red areas (p = 0.008), dotted vessels (p = 0.04), and linear irregular vessels (p = 0.016) were all more frequently present in thin invasive melanomas compared to melanomas in situ. Conclusions: Dermoscopy could predict whether a melanoma is in situ or invasive, but it could not predict the mutational BRAF status in the present study.