Parotid Gland Tumors: Overview and Classification

Parotid gland neoplasms may be benign or malignant, and malignant tumors can be primary or metastatic. Due to the epithelial and the nonepithelial histology of the affected organ, many histological types of parotid tumors with variable biological behavior are possible; there may be considerable overlap between non-neoplastic, benign, and malignant entities. This chapter gives an overview of parotid tumors regarding their epidemiology, etiology, clinical presentation, investigations, and treatment, in addition to the histological WHO classification, which includes over 40 variants as well as tumor-like lesions (e.g., salivary gland cysts). Accordingly, parotid gland tumors are classified into benign, malignant, lympho-epithelioid, and nonepithelial neoplasms, in addition to secondary metastatic tumors.