Ectomesenchymal chondromyxoid tumor

Ectomesenchymal chondromyxoid tumor (ECT) is a benign intraoral tumor with presumed origin from undifferentiated (ecto)mesenchymal cells. There are some who think it is a myoepithelial tumor type.

Patients present with a painless, slow-growing mass usually within the tongue (most commonly the anterior dorsal tongue). There is an intact surface epithelium.

The tumor is quite unique, but other tumors are considered in the differential diagnosis histologically. They included pleomorphic adenoma, myoepithelioma, myxoid neurofibroma, neurothekeoma (nerve sheath myxoma), chondroid choristoma, extraskeletal myxoid chondrosarcoma, focal oral mucinosis, and an ossifying fibromyxoid tumor of soft parts.

Exceedingly rare, this tumor develops in a wide age range, although often in young patients without a sex predilection. The vast majority develop within the anterior dorsal tongue, with palate and base of tongue rarely affected.

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