Nonmalignant Tumors and Lesions

Nonmalignant lesions include benign tumors (eg, glomus tumors, acoustic neuromas) and benign pinnal lesions.

Glomus Tumors

(Paragangliomas)

Glomus tumors are derived from paraganglion tissue (eg, the carotid body); they are benign.

Among tumors of the middle ear and mastoid, which are rare, glomus tumors are the most common.

Symptoms and Signs

The first symptom of a glomus tumor in the ear is usually pulsatile tinnitus, followed by conductive hearing loss. Tumors originating in the middle ear (glomus tympanicum tumors) are clinically evident when small; those originating in the jugular vein at the mastoid (glomus jugulare tumors) become clinically evident relatively late and may produce paralysis of any combination of the 7th, 9th, and 10th cranial nerves, 11th cranial nerve, and 12th cranial nerve. Tumors that infiltrate the labyrinth or 8th cranial nerve cause sensorineural hearing loss. In 1 to 3% of patients, glomus tumors produce catecholamines, which rarely cause intermittent hypertension.

Diagnosis

A pulsatile red mass in the middle ear is diagnostic. Tuning fork testing and audiometry may detect evidence of conductive hearing loss (ie, hearing loss in which bone conduction is much better than air conduction). Cranial nerve testing may reveal characteristic cranial nerve deficits.

Contrast-enhanced CT of the skull base and temporal bone is done because a glomus tumor must be distinguished from a "high-riding" jugular bulb, which is of no clinical consequence. Four-vessel cerebral angiography or magnetic resonance angiography is done to detect occult tumors at other sites, because 7 to 10% of patients with a glomus tumor have multiple tumors.

Treatment

Treatment depends on tumor size and site of origin and the patient's age and general health. In healthy elderly patients, small tumors confined to the middle ear can be surgically removed relatively easily, resulting in little morbidity. Afterward, conductive hearing loss and pulsatile tinnitus may resolve. For elderly patients with large tumors, low-dose radiation therapy (2 to 3 Gy) with arteriographic embolization is the primary treatment. The few patients with hypertension resulting from the tumor must be treated with -blockers and -blockers before and after surgery.

Acoustic Neuroma

(Vestibular Schwannoma)

Acoustic neuroma is a benign tumor derived from Schwann cells that sheathe the vestibular nerve. Patients usually report progressive unilateral hearing loss and tinnitus. Diagnosis is by MRI. Treatment is complete surgical resection, except in patients who are poor surgical candidates because of comorbidity; among such patients, subtotal resection, radiation, or watchful waiting may be recommended.

In the US, acoustic neuromas are diagnosed in 2000 to 3000 people each year. Most acoustic neuromas that occur sporadically (ie, that are not part of neurofibromatosis type 2, a hereditary disorder) are diagnosed in people age 30 to 60. Noise toxicity is an established risk factor.

Symptoms and Signs

Acoustic neuromas most commonly originate in the internal auditory canal. Patients usually report progressive unilateral hearing loss and tinnitus. Often, one ear becomes progressively less useful (eg, when using the telephone). In about ¼ of patients, the unilateral decrease in hearing is sudden. Occasionally, vertigo and disequilibrium develop.

If the tumor grows into the cerebellopontine angle, hearing loss may worsen and vertigo may be gradually replaced by disequilibrium. Large tumors may cause facial numbness (by affecting the 5th cranial nerve) and, eventually, hydrocephalus with visual loss and chronic headache (by collapsing the 4th ventricle).

Diagnosis

A typical audiogram shows asymmetric unilateral sensorineural loss with disproportionate loss of word recognition ability. The acoustic reflex may be abnormal or absent. Performance-intensity function testing for phonetically balanced words may detect rollover (a decrease in discrimination as intensity increases). MRI with gadolinium contrast is required to confirm the diagnosis.

Treatment

Treatment of elderly patients is controversial. Tumor size and the patient's age and health must be considered. MRI may be used to monitor a small tumor in the oldest old who have multiple comorbid disorders that limit function and in those >= 65 who have life-threatening comorbid disorders. Treatment is warranted if tumor size increases. Some surgeons recommend complete surgical excision, as for younger patients, but others recommend a palliative subtotal resection. For elderly patients with vertigo, surgical removal may be recommended even if the acoustic neuroma is small. Radiation therapy (eg, with a gamma knife or linear accelerator [LINAC]) is an alternative for selected patients.

Benign Pinnal Lesions

A variety of systemic disorders, such as gout and RA, can cause pinnal lesions. Gouty tophi, which can be confused with rheumatoid nodules, occur most commonly on the helix. They may be painful and occasionally discharge chalk-white material containing Na biurate. Rheumatoid nodules may also be painful and can develop central necrosis. Treatment is directed at the underlying disorder.

Winkler's disease (chondrodermatitis nodularis chronica helicis), a benign disorder particularly prevalent among elderly men, is caused by collagen degeneration. There is often a history of acute cold exposure or ear trauma. This disorder is characterized by tender, firm nodules on the periphery of the pinna and may be confused with squamous or basal cell carcinoma. Intralesional injection of 0.1 to 0.2 mL of hydrocortisone acetate (25 mg/mL) or triamcinolone acetate (10 to 40 mg/mL) may provide pain relief; local excision may be necessary.

This topic was last updated June 2006.