Pediatric Melanoma: Unique Features and Diagnosis

Overview / Definition Pediatric melanoma is a malignant tumor arising from melanocytes, the pigment-producing cells in the skin. Unlike adult melanoma, pediatric melanoma often presents with distinct characteristics and behaviors, necessitating a tailored approach to diagnosis and treatment. Epidemiology Pediatric melanoma accounts for approximately 1-3% of all childhood cancers, with an incidence rate that has been increasing over the past few decades. Key epidemiological points include: Most common in adolescents aged 15-19 years. Higher prevalence in Caucasian children compared to African American and Asian populations. Male-to-female ratio is approximately 2:1 in older adolescents. Pathophysiology / Mechanism The pathogenesis of pediatric melanoma involves a combination of genetic predisposition and environmental factors. Contributing mechanisms include: UV Radiation: Exposure to ultraviolet light is a significant risk factor. Genetic Mutations: Common mutations include BRAF and NRAS, though they may differ from adult cases. Familial Syndromes: Conditions such as familial atypical multiple mole melanoma (FAMMM) syndrome increase risk. Clinical Presentation Pediatric melanoma often presents differently than in adults, with various clinical features that may include: Types: Superficial spreading melanoma, nodular melanoma, and desmoplastic melanoma are the most common types in children. Lesion Characteristics: Melanomas may appear as irregularly shaped moles with varying colors, diameters >6mm, and changes in existing nevi. Associated Symptoms: Pruritus, ulceration, or bleeding from the lesion may be present. Diagnosis / Workup The diagnosis of pediatric melanoma involves a thorough clinical examination and appropriate diagnostic workup: Clinical Examination: A thorough skin examination is crucial for identifying suspicious lesions. Dermatoscopic Evaluation: Allows for better visualization of lesion morphology. Biopsy: Excisional biopsy is the gold standard for di