Beyond Ultrasound: Multimodal Cross-Sectional Imaging for Preoperative Imaging of Parotid Gland Tumors: A Primer for Radiology Trainees

Abstract

Even if the management of parotid gland tumors depends on the histopathological subtype, preoperative imaging of parotid gland tumors is clinically relevant. Preoperative imaging gives insight into the differentiation between benign and malignant tumors, which might potentially decrease the number of unnecessary aggressive surgeries. Characteristic imaging findings on cross-sectional imaging, such as computed tomography (CT) and magnetic resonance imaging (MRI), can help narrow the differential diagnosis and guide the further management of patients presenting with parotid masses. While MRI is imperative for the determination of perineural spread, which is frequently encountered with malignant parotid tumors, CT is important for the evaluation of osseous invasion. Furthermore, multi-parametric MRI protocols provide insights into the tumor behavior and internal composition, which is helpful in the case of benign mixed tumors and others. While distant metastasis is uncommon with parotid neoplasms, PET/CT provides a valuable tool for the improved evaluation of loco-regional and distant metastatic disease. This article discusses the imaging features of common benign and malignant parotid tumors.