Myoepithelioma in the parapharyngeal space report of two cases and review of literature

Abstract

Introduction: Myoepithelioma (ME) is a benign tumour in 40% of cases located in the parotid gland, accounting for <11.5% of all salivary gland tumours. Myoepitheliomas arise from myoepithelial cells, which are present in major and minor salivary glands, but also lacrimal glands, breasts, and sweat glands. They are seen more often between the fourth and fifth decade of life, without sex predominance. Patients mainly complain about painless, slowly growing mass. MEs in CT are characterized as well-circumscribed small, unilocular, round tumours with smooth or lobulated contours; they may contain enhancing nodules and non-enhancing areas and exhibit homogeneous signal intensities or densities based on MRI. Deep lobe parotid tumours may occasionally grow along the stylomandibular tunnel into the parapharyngeal region resembling dumbbell shape. Tumours of the parapharyngeal space are rare and account for 0.50.8% of all head and neck tumours. Patients have an intraoral mass or asymmetry of the palate, with difficulties in swallowing or phonation. Operative removal with capsule preservation is the treatment of choice. The approach depends on the size of the tumour: cervical, transoral, transparotid, mandibular osteotomy approach or a combination of these. MEs may be locally aggressive, especially in long-standing tumours or in tumours with multiple recurrences. Case report: The authors present two cases of myoepithelioma in the parapharyngeal space.