Computed tomography of major salivary gland tumors. A retrospective study of 31 cases.

To assess the value of computed tomography (CT) in grading (benign versus malignant) and characterization of salivary gland tumors we retrospectively analysed the CT examinations of 31 histologically proven cases (15 pleomorphic adenomas, 6 cystadenolymphomas, 1 lipoma, 4 malignant tumors, 4 cysts, and 1 abscess). Subsequently we studied the localization, size, shape, margins, intratumoral calcification, central lucency, local invasion, homogeneity, density, degree and pattern of enhancement after intravenous contrast injection, and presence of enlarged locoregional lymph nodes. A lesion with ill-defined margins, local invasion, diffuse spread throughout the gland and enlarged locoregional lymph nodes was considered malignant. All malignant lesions were correctly diagnosed (no false negative) but 3 benign lesions had malignant features on CT (3 false positives). Further characterization between pleomorphic adenomas and cystadenolymphomas is often impossible. A cystic lesion with papillary contrast-enhancing projections was found in 2 out of 6 cystadenolymphomas and not in other lesions.