Adenoid Cystic Carcinoma of the External Auditory Canal

Objective/Hypothesis: To describe the clinical history and outcome of patients with adenoid cystic carcinoma (ACC) of the external auditory canal (EAC). Study Design: Retrospective case series. Methods: A search of our institution's tumor registry identified 22 patients with ACC of the EAC. Both clinical histories and pathology slides, when available, were reviewed. Results: The mean age at diagnosis was 42 years (median, 38.5 years), and the most common presenting complaints were otalgia and ear canal mass. Nine patients (41%) developed recurrences at a mean of 8 years (median, 8 years) after initial diagnosis, six died of ACC, and three were living with distant metastases at their last follow-up. The mean duration of symptoms at the time of diagnosis was 7.7 years (range, 2-30 years) for patients who developed a recurrence after treatment vs. 1.2 year (range, 0-2 years) for patients who remained disease-free (P = .137). Every patient who had recurrent disease reported a duration of symptoms of :2 years (P = .013), and every patient with a duration of symptoms >2 years recurred (P = .002). There was a trend for more local recurrences after limited resection (P = .061). Conclusions: ACC of the EAC often recurs many years after definitive treatment. Although our sample size was too small to make definitive conclusions, we recommend aggressive local therapy with lateral temporal bone resection and adjuvant postoperative radiotherapy. In addition to successful local therapy, early diagnosis may be the only other effective means of preventing distant metastases.