Rare Tumors of the Skin and Subcutaneous Tissues

The clinical diagnosis of cutaneous tumors in a child may be a challenge not only due to the rarity of the diseases but also because benign lesions may have alarmingly malignant tumor-like features as well as malignant neoplasms may present with benign characteristics (i.e., pedunculated or amelanotic melanoma simulating a pyogenic granuloma). The same can be said for the pathological diagnosis. For some histotypes, the histological diagnosis of a tumor of the skin in a child can be very difficult for many reasons. For example, the diagnosis of melanoma in pediatric age has often been a problem for pathologists. Melanoma is a very rare entity in children, so pathologists are always psychologically tempted to find an alternative diagnosis. Actually, pediatric melanomas do exist and deserve a distinct treatment. In pediatric age, the ­histological characteristics of melanoma are mimicked by other more frequent neoplasms, i.e., Spitz tumors, for which a spectrum of aggressiveness is reported from benign lesions (Spitz nevi) through the so-called atypical lesions (atypical Spitz tumors, with a risk ranging from low to high) up to the Spitzoid melanoma.