Tumors arising from the glandular structures of the external auditory canal.

Abstract

Neoplasms in the external auditory canal (EAC) of ceruminous gland origin have been generally classified under the title of ceruminoma, which is inaccurate and misleading. There have emerged four distinct types of ceruminous gland tumors of the EAC. They are 1. ceruminous adenoma, 2. adenoid-cystic carcinoma, 3. ceruminous adenocarcinoma, and 4. pleomorphic adenoma (mixed tumor). The natural course and clinical approach to these tumors can be determined by accurate histopathologic evaluation. This paper presents 10 cases of tumors of glandular origin in the EAC, 4 cases being ceruminous adenomas, 3 cases being adenoid-cystic carcinomas, 2 cases being ceruminous adenocarcinoma, and 1 case of pleomorphic adenoma (mixed tumor). In reviewing these cases as well as those in the literature, a number of recommendations are suggested: 1. Identifying a tumor of the glandular structures of the EAC solely as a ceruminoma is no longer acceptable without accompanying histologic specificity. 2. Early wide excisional biopsy is imperative for diagnosis. 3. The signs and symptoms of the tumor do not always correlate with the histopathologic diagnosis and subsequent clinical behavior of these tumors. 4. Ceruminous adenoma and pleomorphic adenoma are benign tumors and are best treated only by wide local excision. 5. Adenoid-cystic carcinoma and ceruminous gland adenocarcinoma are pernicious, malignant tumors which are best treated, in general, by an initial aggressive wide en bloc surgical resection or, if there is extension to the middle ear and temporal bone, by resection of the temporal bone and contiguous structures. 6. Postoperative irradiation has an essential role in managing these malignant tumors. 7. Five year survival rates for the malignant tumors do not reflect the biological behavior pattern of "late" local and distant recurrence and metastasis.