2 Cases of Adenoid Cystic Carcinoma of the External Auditory Canal / 대한이비인후과학회지

ABSTRACT

Adenoid cystic carcinoma (ACC) is rare malignant tumor that affects major and minor salivary gland, ceruminous glands, and occasionally excretory gland of the female genital tract. While ACC accounts for less than 1% of all head and neck malignancies and approximately 10% of all salivary neoplasm, this tumor is one of the most common malignancies of the submandibular and minor salivary glands. ACC is characterized by a slow rate of progression, a tendency for perineural invasion, and a high recurrence rate after intensive surgery and adjuvant radiotherapy. ACC is divided into 3 types according to a distinctive histologic pattern. It is well known that the histologic pattern of ACC correlates well with the grade of tumors and prognosis. There are no clear guidelines for the treatment of ACC, but recently a combination of surgery and postoperative radiotherapy has been recommended. The most significant prognostic factors are clinical stage and distant metastasis. We present two cases of ACC arising from external auditory canal with a review of literature.