Inflammatory Myofibroblastic Tumors of the Middle Ear: An Unpredictable and Aggressive Disease

Inflammatory myofibroblastic tumour is a rare disorder of unknown aetiology first described in the lung. Inflammatory myofibroblastic tumour of the middle ear accounts for only a small portion of this disease and tends to have a more aggressive and unpredictable course than the disease at other sites of the body. Fewer than 20 cases of inflammatory myofibroblastic tumour of the middle ear have been reported in the English literature thus far. We present a case of inflammatory myofibroblastic tumour in a 46-year-old man with unilateral hearing loss. Computed tomography (CT) imaging showed dehiscence of the promontory. Initial biopsy failed to diagnosis the disease, as in many other cases we reviewed. The mass was extensive and eroded several cortical bony structures. The patient underwent radical mastoidectomy and final pathology exam confirmed the diagnosis. We review the key radiological and histological results that should be considered for making a diagnosis of inflammatory myofibroblastic tumour, and discuss the possible differential diagnosis. We also present a review of previously reported cases to help better understand the clinical entity of this disease.