Multiparametric Magnetic Resonance Imaging Versus Fine Needle Aspiration Cytology for Parotid Gland Neoplasms

Parotid gland tumors are mostly treated surgically, but the extent of parotidectomy is decided upon preoperative work-up information. Preoperative management generally includes clinical evaluation, collection of a pathological sample, most often through fine-needle aspiration cytology (FNAC), and imaging. FNAC, despite its high sensitivity and specificity, has the drawback of an approximately 20 per cent rate of nondiagnostic or indeterminate result. Magnetic Resonance Imaging (MRI) provides the best morphological description of the lesion, which is helpful to the surgeon for the planning of the intervention. Recently, advanced functional techniques have been introduced, in association to the conventional morphologic ones: diffusion-weighted imaging (DWI) and dynamic contrast-enhanced imaging (DCEI) demonstrated the ability to provide information about the possible histological origin of parotid lesions. Multiparametric MRI (mp-MRI) comes from the combination of anatomical and functional sequences. The Authors postulate that mp-MRI evaluation may be able to provide information not only about the extension of the lesion, but also about histology, with a high accuracy, at least comparable to ultrasound-guided FNAC. In the present study, the Authors aim to define the value of FNAC and mp-MRI in the preoperative management of parotid gland tumors, comparing their success intended as the capability of the exam to be both diagnostic and accurate in formulating the correct histological suspect of malignancy. Participants are patients affected by parotid gland neoplasms, candidates for surgical resection. The lesion will preoperatively be assessed with both clinical evaluation, ultrasound-guided FNAC and mp-MRI in our Institution. Mp-MRI includes conventional sequences, DWI and DCEI; its interpretation will allow the definition of the suspect histology. FNAC and mp-MRI suspects will be compared to the final histopathological report after surgical removal of the neoplasm.