Dermoscopic features causing confusion between melanoma and benign nevi in clinical diagnosis - case series.

UNLABELLED

The vast majority of melanoma lesions show typical dermoscopic features such as the presence of atypical pigmented network, the variety of colors within nevi, the asymmetry of structures and the presence of structureless areas. The clinical appearance of melanocytic lesions evolving over time also constitutes a clue to discover their malignant potential. Albeit there are some cases that do not exhibit typical dermoscopic and clinical findings suggesting their malignant potential.

A CASE REPORT

We report 4 cases of melanoma with their equivocal dermoscopic images and ambiguous clinical pictures. We acknowledge dermoscopic features such as: the presence of variform, peripheral globules suggesting the possible growth of the nevus, the presence of terminal hair within the melanoma lesion and we confirm that only on the basis of this criterion we cannot qualify such melanocytic lesions to the benign category. We also report the case of the two-component lesion consisted of reticular-homogenous pattern and concentrated globules in the superior pole of the nevus with no significant signs of evolution during one year period of surveillance and the case of the two-component lesion consisted of reticular - homogenous pattern with focal areas of higher density network and the presence of polymorphous, dotted, coiled, comma-like vessels which met the criterion of the ugly duckling sign. Dermoscopy is the most useful noninvasive diagnostic tool designed to discriminate skin nevi. Despite its benefits, the interpretation of a dermoscopic image is not always unequivocal. Some melanoma lesions exhibit only single features included in the assessment algorithms used in everyday dermatological practice such as: the ABCDE rule, the pattern analysis, the 7-points Glasgow checklist, the Menzies method, the 3-point checklist. The presence and the shape of vessels within nevi also constitute an important diagnostic indicator of melanoma. Dotted vessels are related to early stages of melanoma and polymorphous, elongated, linear, vessels are connected with more advanced stages. Therefore, dermoscopic examination should be performed by trained physicians. In case when predicted biological potential of melanocytic lesions is uncertain the excision of suspected lesions followed by histopathological examination should be carried out.