Imaging of pediatric cutaneous melanoma

Metastatic Melanoma in Young Child

Pediatric melanoma is a rare cancer, especially in young children, and it remains a diagnostic challenge. We report a case of massively metastatic melanoma in young patient with an atypical clinical and biological presentation and with no risk factors.

The Challenge of Melanocytic Lesions in Pediatric Patients: Clinical-Pathological Findings and the Diagnostic Value of PRAME

Pediatric melanoma is a rare disease especially in children aged younger than 10 years old. Recent estimates report a rise of disease incidence in both adults and children. Diagnostic work-up is challenging in pediatric melanoma, as it displays a wide range of clinical presentations. Immunohistochemical biomarkers have been reported as predictors of malignancy in melanoma, however data specific to pediatric melanoma are poor. Our study aims to contribute to provide evidence of pediatric melanoma clinical features and differential diagnosis in this patient population. We describe our experience with a retrospective case series of pigmented skin lesions including malignant melanoma, atypical spitzoid tumor, and benign nevi in children and adolescents aged less than 16 years. We described the clinical and demographic characteristics of the cohort and evaluated the immunohistochemical expression of the PReferentially expressed Antigen in MElanoma (PRAME) for differential diagnosis of melanoma in children. The series displayed a similar distribution of melanoma between males and females, and the most common site of melanoma onset were the upper and lower limbs. In our cohort, PRAME was negative in most cases. Focal and slight positivity (from 1 to 5% of the neoplastic cells) was observed in four cases (two Spitz nevi and two atypical Spitz tumors). A moderate positivity in 25% of the neoplastic cells was observed in one case of atypical Spitz tumor. Immunohistochemical expression of PRAME might be useful in the differential diagnosis of malignant melanoma.

Identification of key microRNAs of plasma extracellular vesicles and their diagnostic and prognostic significance in melanoma

Melanoma is one of the most highly metastatic, aggressive and fatal malignant tumors in skin cancer. This study employs bioinformatics to identify key microRNAs and target genes (TGs) of plasma extracellular vesicles (pEVs) and their diagnostic and prognostic significance in melanoma. The gene expression microarray dataset (GSE100508) was downloaded from the Gene Expression Omnibus database. Differential analysis of miRNAs in pEVs was performed to compare melanoma samples and healthy samples. Then, TGs of the differential miRNAs (DE-miRNAs) in melanoma were selected, and differential genes were analyzed by bioinformatics (including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment, protein–protein interaction network and prognostic analysis). A total of 55 DE-miRNAs were found, and 3,083 and 1,351 candidate TGs were diagnostically correlated with the top ten upregulated DE-miRNAs and all downregulated DE-miRNAs, respectively. Prognostic analysis results showed that high expression levels of hsa-miR-550a-3p, CDK2 and POLR2A and low expression levels of hsa-miR-150-5p in melanoma patients were associated with significantly reduced overall survival. In conclusion, bioinformatics analysis identified key miRNAs and TGs in pEVs of melanoma, which may represent potential biomarkers for the early diagnosis and treatment of this cancer.