Parotid gland involvement in nasopharyngeal carcinoma.

Abstract

This study documents the imaging findings of parotid gland involvement in nasopharyngeal carcinoma (NPC). This study reviewed the film records of 1,916 patients with NPC seen over a 5 year period. There were 27 (1.4%) patients with parotid involvement. There were 27 CT and 4 MR studies, and the pattern of involvement was categorized into the following groups: (1) parotid nodal involvement; (2) parotid invasion from extracapsular cervical nodal spread; (3) direct invasion by NPC; and (4) diffusely infiltrated gland not related to (2) or (3). In the subset of 27 patients, parotid nodal involvement was seen in 11 (41%) patients. Ten (37%) patients had cervical extranodal spread into the parotid gland. Three patients (11%) showed direct invasion by NPC, and another three patients (11%) showed an isolated and diffusely infiltrated parotid gland. Metastatic NPC may involve parotid nodes. The parotid gland may also be involved by extracapsular spread from enlarged cervical nodes or infiltrated directly by the primary lesion in the nasopharynx.