MRI findings of epithelial–myoepithelial carcinoma of the parotid gland with radiologic–pathologic correlation

Abstract

Purpose This study aimed to describe the MRI findings of epithelial-myoepithelial carcinoma (EMC) of the parotid gland. Materials and methods Seven patients (four males and three females) aged 40–86 years (mean age, 64 years) with histologically proven EMC of the parotid gland who underwent surgical resection after preoperative MRI were enrolled. MRI images were retrospectively reviewed and contrasted with pathological findings. Results Five patients (71%) had predominantly solid lesions, and two (29%) had predominantly cystic lesions. All seven lesions had well-demarcated margins and capsules without the invasion of adjacent structures. The capsules were incomplete in five lesions (71%) and complete in two (29%). Four lesions (57%) exhibited a multinodular structure with internal septa. Cystic components were observed in three lesions (43%). On T1-weighted images, the solid components were frequently homogeneous (5/7, 71%), and demonstrated isointensity in five lesions (71%) and hypointensity in two (29%) relative to the spinal cord. On T2-weighted images, the solid components were usually heterogeneous (6/7, 86%), and demonstrated hyperintensity in five lesions (71%) and isointensity in two (29%) relative to the spinal cord. The mean apparent diffusion coefficient value of the solid components was 0.967 × 10−3 mm2/s. Conclusion Parotid gland EMCs usually appeared as predominantly solid lesions with well-demarcated margins and capsules. A multinodular structure with internal septa was characteristics of EMCs.

Advanced magnetic resonance imaging findings in salivary gland tumors

“…On conventional MRI, EMCs are well-contoured, may contain mostly solid or cystic components, septa or multi-nodularity can be detected, solid components are isointense or hypointense on T1WIs, hyperintense or isointense on T2WIs, contrast-enhancement with different forms (homogeneous or heterogeneous; moderate, mild or none) can be seen as masses. On DWI studies, ADCmean values of EMCs were reported to vary from (0.96-1.05) ± 0.03 [range (0.789-1.14) × 10 -3 mm 2 /s][ 80 ].…”

A rare case of epithelial-myoepithelial carcinoma ex pleomorphic adenoma of the parotid gland: Radiologic-pathologic correlation

“…The most common histological types are salivary duct carcinoma and myoepithelial carcinoma [3] . EMCa accounts for only 1% of all salivary gland tumors, with an average age of onset of 60-70 years and slight female predominance [4] , [5] , [6] . Seethala et al.…”

“…Suto et al. [5] reviewed the MRI findings of EMCa of the parotid gland. In their study, imaging features were correlated with histopathological findings such as margin, capsule, multinodular structure, septa, predominance, and signal intensity patterns.…”

“…The most common histological types are salivary duct carcinoma and myoepithelial carcinoma [3] . Epithelial myoepithelial carcinoma (EMCa) accounts for only 1% of all salivary gland tumors [4] , [5] , [6] . Here, we report a rare case of EMCa ex pleomorphic adenoma of the parotid gland with a radiologic-pathologic correlation.…”

Current State of Artificial Intelligence in Clinical Applications for Head and Neck MR Imaging

“…MRI is often used to investigate a parotid tumor’s diagnosis based on various imaging findings (mainly T2WI and CE-T1WI). 85 However, the imaging findings of parotid gland tumors are sometimes unspecific and often difficult to diagnose even by radiologists who specialize in the head and neck. Chang et al demonstrated the differentiation of parotid tumors among pleomorphic adenoma, Warthin tumor, and malignant tumors with the use of 2D U-Net and five types of MRI sequences (T1WI, T2WI, CE-T1WI, DWI with b-value of 0 s/mm 2 [DWIb0], DW with b-value of 1000 s/mm 2 [DWIb1000], and ADC) with a fully automated method.…”