Nodular fasciitis of the external ear region: a clinicopathologic study of 50 cases

Nodular fasciitis (NF), uncommon in the auricular area, is a benign reactive myofibroblastic proliferation that may be mistaken for a neoplastic proliferation. Fifty cases of NF of the auricular region were identified in the files of the Otorhinolaryngic-Head and Neck Tumor Registry of the Armed Forces Institute of Pathology. The patients included 22 females and 28 males, aged 1 to 76 years (mean, 27.4 years). The patients usually presented clinically with a mass lesion (n = 49). Five patients recalled antecedent trauma. The lesions were dermal (n = 28) or subcutaneous (n = 11) in those cases where histologic determination was possible, measuring 1.9 cm on average. The majority of the lesions were circumscribed (n = 38), composed of spindle-shaped to stellate myofibroblasts arranged in a storiform growth pattern, juxtaposed to hypocellular myxoid tissue-culture-like areas with extravasation of erythrocytes. Dense, keloid-like collagen and occasional giant cells were seen (n = 18). Mitotic figures (without atypical forms) were readily identifiable. By immunohistochemical staining, myofibroblasts were reactive with vimentin, actins, and CD68. All patients had surgical excision. Four patients (9.3%) developed local recurrence and were alive and disease free at last follow-up. All patients with follow-up (n = 43) were alive or had died of unrelated causes, without evidence of disease an average 13.4 years after diagnosis. Nodular fasciitis of the auricular area occurs most often in young patients. Because NF is more often dermally situated than extremity NF, it may present with superficial ulceration and/or bleeding. Local recurrence is more frequent because of the difficulty in obtaining complete surgical excision around the ear.