Malignant eccrine spiradenoma of the external ear.

Eccrine spiradenoma is a benign tumor of sweat gland origin. Malignant eccrine spiradenoma is a rare neoplasm which almost always arises from a pre-existing spiradenoma lesion. In this article, we present a patient with malignant eccrine spiradenoma of the auricula with a prior diagnosis as benign eccrine spiradenoma. Although malignant transformation is usually associated with aggressive behavior, we did not detect recurrence or metastasis in four years of follow-up after performing wide excision.