[Primary adenomatous tumor of the middle ear: a case report]

A case of primary adenomatous tumor of the middle ear is described. A 16-year-old male was admitted with a one-year history of left hearing disturbance. Skull X-ray disclosed destruction of the left petrous bone. Computed tomographic scans revealed an iso-dense mass in the left petrous bone, which was slightly enhanced. The tumor appeared as a low intensity mass on T1-weighted magnetic resonance image (MRI) and as high-intensity mass on T2-weighted MRI, and was enhanced by Gd-DTPA. Fluid in the peritumoral area showed high intensity on T1- and T2-weighted MRI. External carotid angiography revealed a marked tumor stain fed by the ascending pharyngeal artery. At operation, the tumor was found to be soft and to bleed easily. Histological diagnosis was adenomatous tumor presenting a papillary pattern. Adenomatous tumor of the middle ear is rare and difficult to classify. Nevertheless, papillary adenomatous tumor of the middle ear could often be aggressive and malignant in behavior and this patient will require long-term follow up. This is the first report to our knowledge of MRI findings about primary adenomatous tumor of the middle ear.