Non-contrast computed tomography and magnetic resonance imaging features of mucoepidermoid carcinoma in the salivary glands.

Background: Use of contrast-enhanced cross-sectional imaging is considered standard practice for investigating mucoepidermoid carcinoma (MEC) in the salivary glands. The purpose of this study was to present the common features of MEC on computed tomography (CT) and magnetic resonance imaging (MRI) without contrast enhancements, and to investigate the possibility of discriminating between MEC and pleomorphic adenoma based on the features observed on both modalities. Methods: Twenty cases of biopsy-confirmed MEC originating in the salivary glands were reviewed and characterized by two oral and maxillofacial radiologists with regard to the following aspects: detectability, margin, border, encapsulation, content, contrast between lesion and masticator muscle, and bone changes. Results: Ninety percent of bone changes caused by MEC were detected by CT and sixty-nine percent of tumor existences were detected by MRI. The lesion border could provide a clue to distinguish MEC from pleomorphic adenoma. Conclusions: Observation of MEC features was possible by both CT and MRI. Among the features, the lesion border could be a clue to distinguish MEC from pleomorphic adenoma. [ABSTRACT FROM AUTHOR]