[Solitary mast cell tumor. A case comunication].

Background: The solitary cutaneous mastocytoma is a variant of cutaneous mastocytosis which carries a good prognosis. It may develop at a very early age, during the first weeks of life, or even be congenital. Typically, they present as red-brownish lesions that may be asymptomatic or present systemic manifestations associated with histamine release.

Case report: A 19-year-old female patient who attended a medical consultation for a pigmented lesion, slightly raised in the left antecubital fold, asymptomatic, of recent appearance and progressive growth. Dermoscopy reported a fine symmetrical network, yellowish-brown in color and randomly distributed black dots. The pathology report and immunohistochemical findings were consistent with mast cell tumor.

Conclusions: The solitary cutaneous mastocytoma should not be considered as an exclusive entity in the pediatric population. Acknowledgment of its atypical clinical presentation with its dermatoscopic features, is useful for diagnosis.