SOME ISSUES OF SURGICAL TACTICS IN THE TREATMENT OF PIGMENTAL NEVUS IN CHILDREN

This review provides an update on common melanocytic nevi forms in children, focusing on their dynamic evolution over time. Increasing risk of melanoma in general practice are discussed. Current understanding of the risks associated with congenital melanocytic nevi of different sizes and strategies for the management of children with acquired and congenital nevi are also discussed. The aim of the study was to improve the quality of treatment for children by clarifying the indications and methods of surgical treatment of pigmented skin nevi. Pigmented nevi are benign formations, the oc-currence of which at the present stage is associated with the migration in the embryonic period of melanoblasts from the neuroectodermal tube into the basal layer of the epidermis. According to recent researches, nevi in children are divided into congenital melanocytes, which are hamartomas due to clonal proliferation of benign mela-nocytes during embiogenesis, which may exist at birth or appear during the first years of life (the phenomenon of delayed clinical manifestation) and melanocyte nevi. Melanocyte nevi are benign tumors that arise from mela-nocytes that migrate into the skin in the embryonic period after 6 months of age, reach their maximum size in adolescence, and subsequently prone to regression and complete disappearance [3, 4]. All nevi are divided into melanoma-dangerous (pigmented borderline nevus, blue nevus, Otto's nevus, giant pigmented nevus, Dubreias melanosis) and melanoma-safe (intradermal pigmented nevus, fibroepithelial nevus, papillomatous non-vermicular and vermicular [6]. In general, the concept of pigmented nevus combines a number of skin lesions with general clinical and histological signs, a developmental disorder formed by mature or almost mature components of the epidermis, sebaceous glands, hair follicles, apocrine and eccrine sweat glands and their combinations. Pigmented nevi in 80% of cases are observed in the first year of life and are sporadic [7]. Indications for prophylactic removal of nevi are derived from the analysis of clinical material: symptoms' intensify, in particular, the growth of a nevus, a history of the factors contributing to enhancing pigmented nevi (increased solar radiation, trauma, hormonal changes), the presence of signs of cell proliferation in a cytogram, the presence of elevated temperature zone in the projec-tion of a pigment nevus. A morphological research should be a mandatory condition for preventive surgery. The amount of tissue removed depends on the type of growth, nevus size. Due to the large number of pigmented nevi of different localization in childhood and a careful approach to determining the indications for surgical treatment, in the last decade there has been an extensional annual increase in the number of operated children. Indications for surgical removal of pigmented nevi in childhood should be based on clear clinical dynamic signs, primarily taking into account the localization in functionally active areas. In order to prevent the continued growth of pigmented nevi of any size, it is advisable to cut them within healthy skin in a circle to the fascial layer with simultaneous irradiation with a laser coagulator with a wavelength of 940 nm.