CT and MR imaging findings of salivary duct carcinoma

Abstract

Objective To evaluate the CT and MR imaging findings of salivary duct carcinoma (SDC) in order to enhance the understanding of this rare disease.Methods A retrospective analysis of CT and MRI images was performed in 20 patients (14 males and 6 females,median age 56 years old) with pathologically proved SDC.CT and MR images were evaluated with respect to the following feature factors:location,size,morphology,margin,CT density/ MR signal intensity and enhancement pattern.Results Thirteen lesions were located in parotid gland,4 lesions in submandibular gland,1 lesion in sublingual gland and 2 lesions in the buccal spaces.The maximum diameter of SDC ranged from 1.5 to 7.0 cm,mean (3.5 ±0.9) cm.Five cases demonstrated round or oval round masses with well-defined margin,15 cases demonstrated irregular masses with ill-defined edge.Among them,the peritumoral fat tissues were infiltrated in 7 cases,the preauricular skin were invaded in 3 cases,the jaw muscles were invaded in 2 cases and the parapharyngeal space,pterygoid muscle,retromandibular vein was invaded in 1 case respectively.Lesions were homogeneous in 4 cases and heterogeneous in 16 cases.Seven lesions showed varied calcifications.Lesions were homogeneous iso-intense in 1 case and heterogeneous iso-intense in 2 cases on T1WI,heterogeneous hyperintense in all cases on T2WI.On post contrast images,lesions demonstrated remarkable enhancement in 17 cases,moderate enhancement in 3 cases.Enlarged cervical lymph nodes were found in 12 cases.Conclusions SDC has nonspecific imaging characteristics.CT and MR examinations can accurately demonstrate the extent of tumor involvement and are helpful to provide more comprehensive information for SDC management. Key words: Salivary gland neoplasm; Salivary ducts; Tomography, X-ray computed; Magnetic resonance imaging