Epidermal Choristoma of the Tongue Mimicking a Congenital Melanotic Macule.

We report the fifth case of epidermal choristoma of the oral cavity in a Caucasian newborn with a congenital melanotic macule on the dorsum of the tongue. Epidermal choristoma is an exceedingly rare and benign condition probably caused by a developmental abnormality. It is identified according to the presence of normal skin in an abnormal location. Histologically it is identified according to areas of stratified epithelium and hyperpigmentation of the basal layer along with cutaneous adnexal structures (hair follicles, sebaceous or sweat glands). The clinical presentation is variable, but most of the cases described presented with a congenital lingual pigmented macule. These lesions should be included within the differential diagnosis of congenital lingual macules and distinguished from other entities such as congenital lingual melanotic macules and melanocytic lesions. Surgical excision is the treatment of choice. Epidermal choristoma is a benign condition that probably is underdiagnosed because it is a new and rare entity, and dermatologists should be aware of it.