Perfusion characteristics of parotid gland tumors evaluated by contrast-enhanced ultrasound

Contrast enhanced ultrasound (CE-US) is a promising imaging modality for non-invasive analysis of parotid gland lesions because their vascularisation differs from normal gland tissue. This clinical study should further investigate CE-US as a diagnostic tool for parotid gland tumors.

39 patients underwent CE-US measurements after intravenous application of a contrast agent (SonoVue, Bracco, Italy) before surgical tumor resection. Time-intensity curves gradients were calculated and parameters of intratumoral microcirculation were analysed. The vascularisation parameters were compared among the different tumor entities as defined per definitive histological diagnosis.

Histological analyses revealed 17 pleomorphic adenoma, 15 cystadenolymphoma and 7 malignoma. A significant difference of area below intensity time curve (AUC) and mean transit time (MTT) was measured in the malignant lesions compared to benign tumors (p<0.05). A significant difference of AUC and maximum of signal increase (ΔSImax) for pleomorphic adenoma versus cystadenolymphoma was found (p<0.05).

CE-US seems to be a quantitative and independent method for the assessment of malign and benign parotid gland tumors. Further studies and clinical experience will have to validate this method as a reliable diagnostic tool that facilitates preoperative planning.