Confocal laser scanning microscopy for the diagnosis of dysplastic nevus of the skin

Abstract

In cases of complex differential diagnosis of benign melanocytic neoplasms, dysplastic nevi and skin melanoma, clinical visual inspection and superficial dermatoscopy do not always allow an accurate diagnosis, which is especially important in cases of suspected skin melanoma. In recent years, the method of confocal microscopy has been used for noninvasive skin examination. In the present study, 15 patients with suspected melanoma skin were examined by the method of confocal laser scanning microscopy in cases of complex differential diagnosis (18 melanocytic neoplasms in total). In 8 cases of melanocytic neoplasms, dysplastic nevus was diagnosed. In 10 patients, skin melanoma was diagnosed, which was subsequently confirmed by histological examination of the material obtained after surgical excision. Conducting a comparative analysis of the total incidence of signs of dysplastic nevus showed the unreliability of the confocal microscopy method for differential diagnosis of dysplastic nevus and skin melanoma with orientation only on confocal-microscopic signs of dysplastic nevus. For differential diagnosis of skin melanoma, the presence of the main criteria of malignancy is sufficient: cellular atypia at the site of the dermo-epidermal junction and the disturbance of the papillary architecture of the basal layer. At detection of at least one of these criteria, a diagnosis of skin melanoma was made, which in all cases was confirmed by the results of histological examination. The inclusion of confocal microscopy in the diagnostic algorithm for examining patients with melanocytic skin lesions suspected of melanoma makes it possible to improve the diagnosis of melanoma in the early stages, since the greatest difficulty is the differential diagnosis of dysplastic nevus with early melanoma.