Abstract
Cutaneous melanomas are exceptional in children and represent a variety of clinical situations, each with a different prognosis. In congenital nevi, the risk of transformation is correlated with the size of the nevus. The most frequent type is lateral transformation, extremely rare before puberty, reminiscent of a superficial spreading melanoma (SSM) ex-nevus. Deep nodular transformation is much rarer, can occur before puberty, and must be distinguished from benign proliferative nodules. Superficial spreading melanoma can also arise within small nevi, which were not visible at birth, usually after puberty, and can reveal a cancer predisposition syndrome (CDKN2A or CDK4 germline mutations). Prognosis is correlated with classical histoprognostic features (mainly Breslow thickness). Spitz tumors are frequent in adolescents and encompass benign (Spitz nevus), intermediate (atypical Spitz tumor), and malignant forms (malignant Spitz tumor). The whole spectrum is characterized by specific morphology with spindled and epithelioid cells, genetic features, and an overall favorable outcome even if a regional lymph node is involved. Nevoid melanomas are rare and difficult to diagnose clinically and histologically. They can arise in late adolescence. Their prognosis is currently not very well ascertained. A small group of melanomas remains unclassified after histological and molecular assessment.
Highlights
Published: 1 August 2021Melanoma is a form of cancer arising from melanocytes that occurs mainly but not exclusively in the skin
Nevi are benign melanocytic tumors of the skin defined by an abnormal number of melanocytes present in the epidermis and/or in the dermis, often arranged in “nests” where many melanocyte bodies are grouped in clusters and self-pigment
Congenital melanocytic nevi (CMNi) are benign melanocytic tumors that can be present at birth or become apparent in early childhood
Summary
Melanoma is a form of cancer arising from melanocytes that occurs mainly but not exclusively in the skin. Epidermal hyperplasia encasing numerous small nests with magnification silhouette of SSM, 14-year-old: melanoma and pagetoid Spitz nevus Benign Spitz nevi are frequent during childhood, especially after puberty, and constitute a diagnostic pitfall of melanoma, mostly of the SSM-type. They often appear located on the lower limbs, especially the knee area, or on the face. Rare cases of eruptive nevi have been described, notably in the clinical setting of a nevus spilus [9] These lesions grow rapidly, and their important vascularization and lack of pigmentation clinically suggest a benign vascular tumor, such as a botryomycoma or an angioma. The most common fusions involve NTRK1/3, ALK1, and ROS1, whereas MAP3K8 and ALK1 predominate in atypical and malignant Spitz tumors [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
