Microscopic description and IHC:

Sections of the tissue show nests of cells with dark chromatin and occasionally increased eosinophilic cytoplasm in the background of numerous vascular channels. Mitotic figures are not present.

Immunostaining was positive for synaptophysin and S-100 (sustentacular pattern), and negative for pan-keratin.

Discussion:

Paragangliomas are closely related to pheochromocytomas and are a part of the “Rule of 10s.” Carotid body tumors are the most common paraganglioma in the head and neck region.

Jugulotympanic paragangliomas are the most common tumor affecting the middle ear and have a proclivity for women between the ages of 40 and 69. It is a benign entity and the term “Glomus tumor” is a outdate archaic term.

These benign lesions most commonly arise in the Jugular Bulb (85%) followed by branches of CN IX & X (15%). Morphologically they are composed of nests of small neuroendocrine chief cells (zellballen) in a vascularized stroma.

The cardinal symptom is hearing loss but cranial nerve palsies, dysphagia, and hoarseness may occur if tumor invades into local mastoid temporal bone.

Treatment involves surgical excision ± radiation therapy.

local recurrence happens in 50% of the reported cases.

References:

Wenig, Bruce M. Atlas of Surgical Pathology, 3rd ed. Sept 2015.

Pernick, Nat, MD. "Ear." Pathology Outlines. PathologyOutlines.com, Inc., 31 May 2016. Web. 11 July 2016.

Gnepp, Douglas R. Diagnostic surgical pathology of the head and neck. Elsevier Health Sciences, 2009.

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