CLINICAL CASES OF SPITZOID NEOPLASMS

Abstract

Spitz nevi account for about 2% of the total number of melanocytic skin neoplasms. There are benign Spitz nevi, atypical Spitz tumour, and malignant Spitz melanoma. These clinically similar lesions, usually represented by a flesh-coloured, pink or brownish-black spot or nodule, are often heavily vascularised, grow rapidly in size and change in structure, raising concerns about malignancy. Dynamic observations have revealed the possibility of long-term stabilisation and periods of regressive changes. Dermoscopy is used for early diagnosis due to the initially small size of nevi. When examining the magnified image of the tumour surface, the structure of the neoplasm is recognized. In the case of Spitz nevi, special patterns of “starburst” and “stardust” are identified, which allow to suspect the diagnosis and the period of involution, respectively. Pathohistologically, Spitz nevi are defined as melanocytic proliferations with large epithelioid or spindle-shaped melanocytes with large nuclei, vesicular chromatin and prominent nucleoli. However, the differentiation between different subtypes of spitzoid neoplasms remains a difficult issue. As of today, the review of H&E-stained structures still prevails over immunohistochemical and molecular genetic diagnostic methods. Even nowadays, Spitz nevi still cause difficulties in clinical and morphological diagnosis and management approaches. The publication considers several interesting cases from personal clinical practice. Case 1: Patient A, a 24-year-old woman. She complained of a single rash on the outer surface of the right thigh, which gradually increased in size over the last year. On clinical examination, a small erythematous, partially pigmented, heterogeneous nodule was observed in this area. The demonstrated Spitz nevus is heterogeneous in structure. Being in the phase of active growth, it showed an asymmetrical “starburst” pattern formed by vascular elements in a linear arrangement, and white reticular lines or structureless zones. Case 2: Patient B, 34 years old. A full examination of the right popliteal fossa revealed a heterogeneous spot up to 4 mm in diameter, which caused concern. A case of Spitz nevus is represented by a globular pattern in the centre and a reticular pattern on the periphery, which is more common for lesions that have been on the skin for some time, but no longer show signs of active growth. Case 3: Patient C, a 25-year-old woman, skin phototype 2, with a family history of skin tumours in several previous generations. The examination revealed a heterogeneous nodule of suspicious morphology in the left scapula. Dermoscopically, the above-described lesion is represented by two zones of different structure. The central zone has the signs of radial markings formed by various pattern elements; the polychromatic zone has areas of negative pigment network, white lines, dots and globules. There was also an eccentrically located area with a radially oriented hyperchromatic pigment network and a clear border along the outer edge. Most Spitz nevi are independent lesions, but some of them can be associated with other skin neoplasms. This is likely to be the example in the above-mentioned case, so it was the nevus-associated Spitz melanoma. Spitz nevi are an urgent problem of modern medicine. The similarity of the clinical, dermoscopic and pathological picture to malignant skin neoplasms causes diagnostic difficulties. Visual variability requires considerable clinical experience of a specialist.