Випадок із практики / Case from practice 1 КЛІНІЧНА ОНКОЛОГІЯ. 2024, Т. 14, № 1 (53): 1–3 ISSN 2410-2792 M. Voloshynovych 1 , T. Boichuk 2 , N. Matkovska 1 , V. Tkach 1 , V. Voloshynovych 1 , N. Kozak 1 A case of superficially spreading melanoma associated with an intradermal nevus 1 Ivano-Frankivsk National Medical University, Ukraine 2 Lux Skin, Ivano-Frankivsk, Ukraine Received 14.02.2024 Accepted for publication 16.02.2024 DOI: 10.32471/clinicaloncology.2663-466X.53-1.31796 The way melanomas appear has been of considerable interest to researchers for many years. At the current stage of research, the data indicating that this tumour arises de novo, rather than as a result of transformation of a pre-existing skin lesion, are overwhelming. Therefore, cases of melanoma-associated nevi are of considerable clinical and diagnostic interest. The vast majority of such tumours are associated with various types of pigmented nevi, while there are only isolated sporadic descriptions of the transformation of intradermal nevi into melanoma. The publication presents a clinical case of this rare pathology. There are data from clinical examination and dermoscopic examination. The lesion was excised within healthy tissue. Pathohistological study of the material was carried out. The diagnosis of superficially spreading melanoma against the background of intradermal nevus was confirmed. Melanocytes from the epidermis spread into the papillary and reticular layers of the dermis to a maximum depth of 1.4 mm. To clarify the depth of invasion, immunohistochemistry was performed, Breslow 1.0 mm. To exclude microsatellite metastases, re-excision of the site of the previous intervention was performed. The pathohistological structure of the material was typical for a postoperative scar, no signs of tumour growth were detected. The complex visual and dermoscopic structure of associated melanomas can lead to misdiagnosis. The deep location of the primary lesion requires the use of immunohistochemistry to determine the thickness of the tumour. High-quality diagnosis directly affects the further management of the patient. Key words: melanoma; naevus; dermoscopy. INTRODUCTION The way melanomas appear has been of considerable interest to researchers for many years. At the current stage of research, the data indicating that this tumour arises de novo, rather than as a result of transformation of a pre-existing skin lesion, are overwhelming. Therefore, cases of nevus-associated melanomas (NAMs), the incidence of which, according to the results of many multicentre studies, ranges from 20 to 30%, are of considerable clinical and diagnostic interest [1–3]. A statistical analysis of the information indicates that NAMs occur more often in young people, in the trunk area, and are usually represented by a smaller tumour thickness according to Breslow [4]. However, the vast majority of NAMs are associated with various types of pigmented nevi, while there are only a few sporadic reports of the transformation of intradermal nevi into melanoma [5–7]. CASE SYNOPSIS Patient A, 43 years old, consulted a dermatologist with complaints of papillomas on the hands. She had Fitzpatrick skin phototype 2, a history of melanoma in blood relatives, and a history of repeated sunburns. A routine examination of the skin surface revealed a solitary papular rash on the left shoulder blade with a heterogeneous colour (Fig. 1a). Digital dermoscopy with photofixation (FotoFinder Medicam 1000s camera in polarisation mode) was performed. Due to the complex appearance of the lesion, an ultrasound gel was additionally applied to the skin surface. The lesion is heterogeneous, with convex (Fig. 1b) and flat parts (Fig. 1c). The tumour was excised within healthy tissue. A pathohistological study of the material was carried out. The diagnosis of superficially spreading melanoma against the background of an intradermal nevus was confirmed. Melanocytes from the epidermis spread into the papillary and reticular layers of the dermis, to a maximum depth of 1.4 mm ( Fig. 2 a ). To clarify the depth of invasion, Fig. 1. Patient A: a — marker 01. Solitary papular rash on the left scapula; b — convex part of the lesion. Dermoscopy. 20x Polarisation and ultrasound gel; c — flat part of the lesion. Dermoscopy. 20x Polarisation and ultrasound gel