Incidentally detected Carotid Body Tumour : Case Report

Female, 60 years old, with headache and recurrent left tinnitus. Has been to several ENT clinics. Stayed unexplained for 5 Yrs.  MRI brain incidentally detected the finding described below.

Case submitted by Dr. A. Altamimi, MD, DMRD, FRCR, Consultant Radiologist

MRI Brain revealed : special note is the presence of an incidentaloma in the form of a lobulated oval mass (about 2.5 x 3 x 4.5 cm) embedded in the left upper neck at the level of the carotid bifurcation (splaying the ICA and ECA carotid arteries) with some localized mass effect. It is generally iso-to-hypointense to muscle on T1, moderately hyperintense on T2 and FLAIR and becomes even brighter in STIR images and shows a more or less typical salt-and-pepper appearance representing flow voids (pepper) combined with punctate hyperintensities due to slow flow &/or hemorrhage (salt) in keeping with carotid body tumor (aka chemodectoma or carotid body paraganglioma). Brain MRI was otherwise normal.

Overview

Paragangliomas (PGLs) are uncommon tumors, incidence rate is 1 to 2 per 100,000, and the tumors are often given special designations, depending on their locations. Only 3% of all PGLs occur in head and neck, majority located in carotid body (carotid body tumors), temporal-bone/middle-ear (glomus jugulare) and vagus nerve in neck (vagal PGLs). 90% of head and neck PGLs are sporadic, while only 10% are hereditary in nature.

In literature, cases of PGL mimicking thyroid nodules are rarely encountered.

Abstract 

Paragangliomas (PGLs) are neuroendocrine tumors arising from the extra-adrenal chromaffin tissue of the autonomic nervous system. They are most frequently found in the head and neck, mainly associated with the carotid body, vagus nerve, jugulotympanic paraganglia, and occasionally, the superior-inferior paraganglia.

Paragangliomas are rarely encountered in thyroid as well, and thyroid paragangliomas can be misinterpreted as medullary thyroid carcinomas. Tumors associated with arterial vessels and cranial nerves of the ontogenetic brachial arches, usually nonchromaffin and nonfunctioning, like carotid body PGs

Links for further reading

http://www.journalmc.org/index.php/JMC/article/view/1754/1018