Parotid tumors constitute 80 percent of all salivary gland tumors. Around 80% of parotid tumours are benign, pleomorphic adenomas are the most common benign types. Mucoepidermoid carcinoma is the most common salivary malignancy.
There are many diagnostic tools that can be used to reach a final diagnosis of parotid lesions such as: ultrasound imaging, computerized tomography, magnetic resonance imaging and fine needle aspiration cytology. The correct diagnosis before operation is important for the surgeon in order to determine the best surgical procedure.
Magnetic resonance imaging (MRI) is another investigation tool which is superior to ultrasound in detecting parotid tumor location especially in the deep lobe, and provides better results than computerized tomography (CT) in providing anatomic information and displaying the relationship of the mass with contiguous structures.
The MRI findings were of great value in distinguishing benign from malignant parotid gland tumors when biopsy results are non-diagnostic.
Salivary gland tumors are an uncommon entity with highly varied histopathological assessment due to heterogeneous cellular composition. Fine-needle aspiration cytology (FNAC) is a good investigation tool to differentiate benign from malignant parotid tumors, oftentimes FNAC is non diagnostic or yielding false positive or false negative results.