Possible characteristic computed tomography (CT) and magnetic resonance imaging (MRI) findings of parapharyngeal pleomorphic adenoma

This study investigates the possible characteristic Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) findings of parapharyngeal Pleomorphic Adenoma (PA), which is rarely found, reported. We analysed 6 cases that had been diagnosed with nasopharyngeal PA and surgically treated in the last 6 y with both the symptoms of the patients and the characteristics of the tumours. The most frequent symptom was symptom free (4 patients). All the patients had the clinical sign of oropharyngeal mass, which is painless and hard. Three of 6 patients underwent CT plain scan. Five patients underwent CT contrast scan. Only one patient underwent MR plain scan and contrast scan. There are some special imaging findings about this disease: The special pre-styloid location (the prestyloid fat pad is displaced laterally, the carotid artery and the jugular vein are pushed away posteriorly or not displaced, and the styloid process was displaced posteriorly or partly encased by the mass); Locally expanded or lightly invasive growing development; Complicated CT density/MR signal intensity; and the oppressive bone absorption of the posterior part of the maxillary. Although the nasopharyngeal PA is rarely reported, it has some characteristic radiologic findings. The suggestive radiologic methods are MR plain scan, MR contrast scan and CT plain scan to observe the extent, signal, and involvement of the tumour.