Adenomas of the temporal bone.

Three cases of primary adenomas of the petrous bone are presented and compared to an adenoma arising from the external ear canal. In contrast to other adenomatous tumors, these caused slowly progressive inner ear symptoms without other signs, hence making differentiation from other benign lesions difficult. In one case, association with von Hippel-Lindau disease is suspected because of a strong family history and recent discovery of a similar lesion in the opposite ear. Bone destruction was found radiographically and clinically with vascular tumor tissue and cysts permeating the bone, causing adjacent bone destruction and remodeling. The histopathologic examination demonstrated this to be a benign process, however, with no direct tumor invasion or other signs of malignancy. Subtotal petrosectomy is a proven approach for complete removal of these tumors. Review of the literature revealed no previous reports of benign adenomas originating in the petrous bone.