Giant Parotid Pleomorphic Adenoma

Abstract

A 49-year-old woman was referred to the maxillofacial surgery center with a gigantic mass (Panels A, arrow) in the right parotid area. Patient noticed mass`s appearance 3 years ago with painless rapid growth during last year. No loss of function of the facial muscles was noted. No pathologic lymph nodes were also noted clinically and on the multi-slice computed tomography (MSCT), which revealed a large mass with lobulated borders in the right parotid area, displacing masseter muscle and upper portion of the sternocleidomastoid muscle. Pre- (Panels B and D) and post-contrast (Panels C and E) MSCT was performed according to the radiological protocol. Axial scans of the contrast-enhanced MSCT (Panels C and E) clearly demonstrate the polymorphic structure of the mass helping establishing the diagnosis of parotid pleomorphic adenoma. Pleomorphic adenoma is a benign encapsulated tumor with a cellular polymorphism due to which this tumor is also named as a “mixed tumor.” Very often these tumors have incomplete/‘not true’ capsule with a finger-like extensions into the glandular tissue. This anatomical feature requires from the surgeons to avoid a tumor`s enucleation and perform the partial/total resection of the surrounding parotid tissue (parotidectomy) together with a mass. In cases of intratumoral localization of some branches of a facial nerve, the partial/total facial nerve sacrifice is indicated. Such a radical treatment helps to reach two tasks: to avoid recurrence and to avoid possible malignant transformation of the recurrent pleomorphic adenoma.