A Rare Pediatric Melanocytic Case: Perineuromatous Melanocytic Nevus

Öz

Perineuriomatous melanocytic nevus is a rare biphasic entity in the pediatric population, characterized by clinical and histopathological features that may overlap with various cutaneous lesions. Clinically, it often presents as a papule. Histopathological examination typically reveals conventional nevus cells accompanied by a spindle cell component displaying a whorled pattern. Immunohistochemical demonstration of perineuriomatous markers in the spindle component is valuable for diagnostic confirmation. Our case involves a 3-year-old male patient with a congenital polypoid cutaneous lesion excised with preliminary diagnoses of dermal melanocytic nevus, dermatofibroma, and hemangioma. Histopathological evaluation revealed a melanocytic lesion composed of maturing nevus cells, accompanied by a spindle cell component exhibiting a whorled pattern. Immunohistochemical analysis demonstrated CD34 expression in the spindle component, suggesting a perineuriomatous origin. The final diagnosis was reported as perineuriomatous melanocytic nevus. Surgical excision was considered sufficient treatment, and no recurrence was observed during follow-up. Perineuriomatous melanocytic nevus is a recently defined and rare entity in the literature, with only a limited number of pediatric cases reported. Herein, we present our case with a review of the literature to contribute to a better understanding of the clinical, histopathological, and immunohistochemical features of perineuriomatous nevi.

Anahtar Kelimeler

• Perineuromatous nevus
• cd34
• whirl pattern

Pediatrik Nadir bir Melanositik olgu: Perinöromatöz Melanositik Nevüs

Öz

Perinöromatöz melanositik nevüs, pediatrik çağda nadir bildirilen, klinik ve histopatolojik olarak birçok cilt lezyonu ile ayırıcı tanıya giren bifazik bir antitedir. Klinik olarak sıklıkla papül olarak prezente olur Histopatolojik incelemede tipik nevoid hücreler yanısıra girdapsı patern sergileyen iğsi bir komponent izlenir. Tanı teyidi için iğsi komponentin perinöromatöz belirteçlerle immünohistokimyasal yöntemle gösterilmesi kıymetlidir. Olgumuz 3 yaşında erkek hasta olup polipoid yapıda izlenen ve konjenital olduğu belirtilen cilt lezyonu Melanositik Dermal Nevüs, Dermatofibrom ve Hemanjiom ön tanılarıyla eksize edilmiştir. Histopatolojik incelemede matürasyon sergileyen nevoid hücrelerden oluşan melanositik lezyona girdapsı patern sergileyen iğsi bir komponentin eşlik ettiği görülmüştür. Yapılan immünohistokimyasal değerlendirmede iğsi komponentin CD34 ekspresyonu sergilemesi bu komponentin perinöromatöz kaynaklı olabileceğini düşündürmüş ve nihai tanı perinöromatöz melanositik nevüs olarak bildirilmiştir. Olgunun tedavisinde eksizyon yeterli görülmüş, takiplerinde nüks izlenmemiştir. Perinöromatöz melanositik nevüs, literatürde son yıllarda tanımlanan bir antite olup nadir görülmektedir. Pediatrik çağda ise sayılı vaka bildirilmiştir. Biz de perinöromatöz nevüslerin klinik, histopatolojik ve immünohistokimyasal özelliklerinin daha iyi anlaşılması amacıyla olgumuzu literatür eşliğinde sunmak istedik.

Anahtar Kelimeler

• perinöromatöz nevüs
• cd34
• girdapsı patern

Kaynakça

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