Imaging case series of many faces of head and neck paragangliomas

Abstract

In contrast to sympathetically derived (functional) pheochromocytomas of the adrenal gland and extra-adrenal paraganglioma (PGL) in the abdomen, which frequently manifest with hypertension and tachycardia, head and neck paragangliomas (HNPGLs) originate from the paraganglia of the parasympathetic system in the head and neck and are rarely functional.

HNPGLs occur predominantly in five specific locations: the carotid body, vagal region, tympanicum, jugular, and larynx. Although the diagnosis and morphological characteristics remain consistent across these anatomical sites, variations exist in their frequency, genetic syndrome associations, and differential diagnoses. Research suggests that genetic factors play a role in about 40% of all HNPGLs, with many cases occurring without a known family history.

The majority of HNPGLs exhibit benign characteristics and are limited to local invasion, with malignant tendencies observed in just 2–13% of cases.

This review aimed to highlight the uncommon behavior of HNPGL cases encountered at our institute, such as the association with papillary thyroid carcinoma, venous tumorous growth along the entire course of IJV, association with metastatic cervical nodal disease, laryngeal PGL, and multiple synchronous paragangliomas that were clinically diagnosed as inflammatory aural polyps, with accidental discovery of other synchronous non-symptomatic paragangliomas.