Myoepithelioma of the hand and carpal tunnel: An unusual cause of median nerve compression.

Myoepitheliomas are rare tumors increasingly recognized to occur in the soft tissues. Although the hand and carpal tunnel are exceptional locations, the presence of these lesions in such sites constitutes a potential cause of debilitating symptoms. We report the case of a patient with severe pain secondary to median nerve compression and displacement of flexor tendons caused by a rapidly growing myoepithelioma. This is the first sonographic description of this tumor producing carpal tunnel syndrome and disabling pain. High-resolution sonography allowed evaluation of gross tumor morphology and real-time assessment of its interactions with surrounding structures.