GLOMUS TUMORS

GLOMUS TUMORS

Department of Otorhinolaryngoglogy2nd Hospital affliatted to Medical college of Zhejiang Universit

yXu Yaping

2

Definition

Glomus tumors are generally benign neoplasms of arising from neuroectodermal tissues, found in various parts of the body.

3

Pathology

catecholamine + sustentacular cells (modified Schwann cells)

+a rich network of capillaries and venules.---- "zellballen" "light" and "dark" cell subpopulations, referring to the density of

intracellular neurosecretory granules. Chief cells are members of the amine precursor and uptake

decarboxylase (APUD) family, as the DNES (diffuse neuroendocrine system).

related to the adrenal medulla, and their neoplastic counterpart in the adrenal gland is the pheochromocytoma.

4

The extra-adrenal versions have various names including non-chromaffin paragangliomas,

aragangliomas, chemodectomas, glomerocytomas, receptomas, tympanic body tumors, carotid body tumors, and a few others.

5

Synchronous glomus tumors are not the only associated neoplasms. Several authors have reported an association with other neoplasms

(benign and malignant).

Spector et. al. reported a 7% incidence in his series of 95 patients. thyroid C-cell carcinoma,

parathyroid adenomas,

pheochromocytomas,

the MEN syndromes,

visceral neoplasms of neural crest origin.

6

In the head and neck,

two anatomic groups of paragangliomas can be differentiated:

cervical paragangliomas temporal bone ( jugulotympanic) paragangliomas.

7

The cervical group includes primarily carotid body tumors

glomus vagale or intravagale tumors, The jugulotympanic refers to glomus jugulare

glomus tympanicum tumors.

--------- the second most common temporal bone tumors

The first is the acoustic neurinomas.

8

Epidemiology

The incidence of glomus jugulare tumors is 1:1,300,000 population. the predominant incidence in females. The female:male incidence

ratio is at least 4:1. The incidence of malignancy in glomus tumors is believed to be low

(<5%). Patient age averages 50 to 60 years , and highly variable. Catecholamine secreting ( "functional") tumors occur in 1% - 3% of

cases. There is no racial or ethnic predilection.

9

Clinical Presentation

Symptoms are insidious in onset. pulsatile tinnitus: most common, tinnitus is secondary to mechanical

impingement on the umbo is most cases. aural fullness, conductive hearing loss. Sensorineural hearing loss on the side of a glomus tumor is the

hallmark of labyrinthine invasion.

10

Physical examination

a red or reddish-blue mass seen behind the tympanic membrane. The diagnosis of glomus tympanicum can only be entertained if the

examiner can see a full 360 degrees around the perimeter of the lesion, otherwise the presumptive diagnosis must be a glomus jugulare.

The finding of a middle ear mass is fairly reliable, with 94 - 100% of untreated cases demonstrating this in reviews of large series of patients.

14

Brown's sign (blanching of the mass with positive pressure pneumotoscopy) is often mentioned, but the frequency of this finding is not clear.

Rarely, a friable or bleeding mass in the EAC may be the presenting sign with larger tumors.

tachycardia, tremor, or complaints of vascular headaches should alert for the possibility of a functional tumor.

15

Cranial nerve deficits are seen primarily with larger tumors

compression or invasion of CN's IX, and X most commonly CN's VII, VIII, XI, and XII affected less often. Isolated deficits of CN's VII and VIII are more likely to be

secondary to a tympanicum.

16

Diagnosis and Preoperative Evaluation

clinical grounds: the presumptive diagnosis CT, MRI: the size and extent sometimes angiography: the primary blood supply to tumor. A myringotomy for purposes of obtaining tissue should not be

performed on a middle ear mass. If a tissue biopsy is to be obtained (not usually necessary) a

transmastoid approach should be used.

18

Differential diagnoses

neural lesions (neurolemmoma, neurofibroma, chordoma), osteoblastoma,

adenomas, adenocarcinomas, inflammatory polyps, cholesterol granulomas, rare lesions such as histiocytosis, fibromyxoma, melanoma,

rhabdomyosarcoma, lipoma, plasmacytoma, or metastatic lesions (lung, breast, prostate),

almost all of these can be excluded with the appropriate physical examination and radiological studies.

19

Treatment

surgical excision: Glomus Tympanicum

The appropriate treatment of glomus tympanicum tumors isolated to the middle ear, middle ear and mastoid, or even the inner ear (Fisch classifications A & B)

Glomus tympanicums can be completely excised in over 90% of cases with standard otologic approaches.

20

Glomus Jugulare:

surgical excision, radiation therapy, surgery and radiation, or observation.

The argument over the relative merits of surgery vs radiation center on their complications and efficacy. With advances in skull base techniques, surgery is generally efficacious, so the decision on treatment mode often centers on the potential morbidity of the surgery, and other patient factors.

Thank you!

GLOMUS TUMORS

Documents

Transcript of GLOMUS TUMORS