Myxomas of the external ear and their significance.

Myxomas of the external ear are extremely rare. We describe 27 such tumors in 22 of 152 patients with the complex of myxomas, spotty pigmentation, endocrine tumors, and schwannomas--a familial (autosomal dominant) syndrome. Eleven of the patients were male, and 11 were female; age range was from birth to 41 years. Nine patients were members of three affected families. The external auditory canal and the external ear were involved in 18 and five patients, respectively; in two, the exact ear location was not known. Three patients had both ear canal and external ear lesions. Two patients with ear canal myxomas had bilateral lesions. Six patients had recurrences after simple excision. The ear canal lesions often were accompanied by deafness due to occlusion of the canal; attachment to the canal wall was usually by a pedicle. Grossly, the lesions were mucoid and from 3 mm to 2 cm in greatest dimension. Microscopically, they were circumscribed but not encapsulated and were composed of scattered stellate and spindle cells set in a myxoid, capillary-rich matrix. An epithelial component (epidermal inclusion cysts or basaloid buds or both) was present in 14 tumors. Cardiac myxoma occurred in nine patients, Cushing's syndrome in three, and psammomatous melanotic schwannoma in three. In two patients, the ear myxoma was the presenting sign of the complex. Patients with myxoma of the external ear (and their primary relatives) should be considered at risk for the complex of myxomas, spotty pigmentation, endocrine tumors, and schwannomas and should be examined accordingly.