Magnetic Resonance Imaging and Histopathology in a Case of Pleomorphic Adenoma of a Minor Salivary Gland in the Nasal Cavity.

BACKGROUND Pleomorphic adenoma of the salivary gland is a common benign tumor of the parotid gland. However, pleomorphic adenoma arising in the minor salivary glands, including the nasopharynx, is uncommon. This report is of a case of nasal pleomorphic adenoma in which the preoperative imaging findings were consistent with the histological features of pleomorphic adenoma of the minor salivary gland, which differs from that of pleomorphic adenoma of the major salivary gland. CASE REPORT A 56-year-old Japanese man was referred to the department of otolaryngology following nasal endoscopy performed at a referral center that identified a right nasal mass. The findings of contrast-enhanced magnetic resonance imaging (MRI) were consistent with a pleomorphic adenoma arising in the nasal septum. Needle biopsy and histology confirmed the diagnosis of pleomorphic adenoma. The tumor was resected using endoscopic surgery, and the histology confirmed the diagnosis of pleomorphic adenoma covered by normal nasal mucosa. CONCLUSIONS This case showed that pleomorphic adenoma arising in the nasal minor salivary gland had typical MRI and histological findings and was a submucosal lesion. Preoperative MRI supported the approach to surgical resection to ensure complete excision.