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Interferon therapy has not proved to be as useful as early reports predicted. Other medical therapies are under investigation.

Recurrence and spread are currently common.

Adult type. In this form, the papilloma is generally single.

As in the juvenile form, the papilloma tends to recur following excision.

Recurrent lesions can undergo malignant transformation, particularly in patients exposed to radiation.

C

Nasal polyps are rare before 5 years of age and occur more commonly in men.

Etiology. Nasal polyps are believed to be an allergic response, but this etiology has not been clearly established.

They may be associated with asthma and an idiosyncratic reaction to aspirin.

In children, the presence of nasal polyps should prompt a sweat test to rule out cystic fibrosis.

Characteristics

Inflammatory polyps are almost always bilateral and may recur frequently.

Involvement of the paranasal sinuses is common.

Treatment. Polyps are excised if they obstruct the nasal airways or the sinus drainage pathways.

D Fibrous lesions

Nodular (proliferative) fasciitis presents as a rapidly growing, discrete soft tissue mass.

Etiology

Probably a reactive, non -neoplastic response to injury, it may occur at any time from childhood to age 70.

The lesions may be mistaken for sarcoma.

Characteristics. Fascia is the primary tissue involved.

Treatment. The lesions generally do not recur after excision.

Proliferative myositis occurs in adults and appears to be post-traumatic in origin.

Characteristics

Like nodular fasciitis, it can be confused with sarcoma.

The lesion involves muscle diffusely.

Occasionally, spontaneous regression occurs.

Treatment. Lesions do not recur after excision.

Traumatic myositis ossificans, bony deposits in muscle due to trauma, generally presents as a painful mass in the muscle 1–4 weeks after a single severe trauma.

Characteristics

In the head and neck, the masseter or sternocleidomastoid is generally involved.

Radiography reveals feathery opacities or irregular radiodensities.

The condition must be differentiated from myositis ossificans progressiva , which is a progressive, systemic illness that begins early in life and results in the conversion of muscle tissue to bony tissue.

Treatment. Persistent painful masses are excised. Local recurrence is common.

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Desmoid tumors are benign, locally invasive, encapsulated tumors.

Etiology

They arise from the muscle fascia and are often associated with prior trauma.

These tumors are uncommon in the head and neck but, when found, usually arise from the sternocleidomastoid muscle.

Treatment. Complete surgical excision is the treatment of choice.

E Tumors of skeletal muscle

Characteristics

Extracardiac rhabdomyomas have a predilection for the head and neck.

They show a slight male predominance.

Signs and symptoms depend on the site and size of the tumor.

Treatment. Rhabdomyomas are treated with complete surgical excision, if possible, followed by chemotherapy and radiation.

F Tumors of peripheral nerves

(see Chapter 26, II B 6)

Schwannomas are solitary, encapsulated tumors attached to or surrounded by a nerve. They are primarily located centrifugally and are often painful and tender. They are not associated with von Recklinghausen's disease or with malignant change, in contrast to neurofibromas.

Acoustic neuromas constitute a type of schwannoma.

Etiology. They arise from the eighth cranial nerve, usually start within the internal auditory canal, and can involve the cerebellopontine angle.

Characteristics. Signs and symptoms may include hearing loss, tinnitus, imbalance, and vertigo. Asymmetric sensorineural hearing loss is common and requires that acoustic neuroma be ruled out.

Evaluation. Testing includes an audiogram, an auditory brain stem response test, and an MRI with gadolinium enhancement.

Treatment. Early discovery is important because it results in earlier resection, with a consequent decrease in morbidity and mortality.

Von Recklinghausen's neurofibromatosis (NF I)

Etiology. It is caused by a nerve growth factor gene on chromosome 17q11.2. Inheritance is autosomal dominant.

Characteristics

Neurites (axons) pass through the tumor.

Lesions are usually multiple and unencapsulated.

In 8% of patients, neurofibromas undergo malignant changes.

Usually, these lesions are located centripetally and are characteristically asymptomatic.

Café au lait spots, vitiligo, gliomas (especially optic), osseous changes, Lisch nodules (iris hamartomas) meningitis, spina bifida, syndactyly, hemangiomas, axillary or inguinal freckling, NF I in a first -degree relative, or retinal and visceral manifestations may be present.

Central neurofibromatosis (NF II)

Etiology. It is caused by an abnormality on chromosome 22q11.21 -13.1 and involves encoding of a suppressor protein called schwannomin . Inheritance is autosomal dominant, but almost 50% of cases are new mutations.

Characteristics

Classically, slow -growing, bilateral acoustic neuromas or neurofibromas cause hearing loss or dizziness and lead to a diagnosis by age 20.

The diagnosis may also be established by a unilateral eighth nerve mass and:

A relative with NF II or,

Any two of the following: glioma, juvenile posterior subscapular lenticular opacity, meningioma, neurofibroma schwannoma

Café au lait spots, posterior lens cataracts, and cutaneous neurofibromas are uncommon. Lisch nodules are not found.

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Wishart type: Early onset rapid growth, other fibromatous tumors in addition to eighth nerve masses

Gardner type: Later onset, slow growth rate, usually bilateral acoustic neuromas only

Traumatic neuromas are reactive hyperplasias due to a nerve's attempts at regeneration after injury. They are generally oval or oblong, gray, firm, and unencapsulated. Persistent hyperesthesia and tenderness are the usual signs.

Most neurogenous tumors of the head and neck can be excised safely without sacrificing nerves. If an important nerve must be cut, it should be generally reanastomosed or a nerve graft should be interposed.

G Granular cell tumors

Congenital epulis occurs on the gum pads of newborns in the region of the future incisors. The lesion can be quite large, does not recur after excision, and may spontaneously regress. The female:male ratio is 8:1.

Nonepulis form of granular cell tumors occurs mainly in young adults, especially in blacks.

H

Paragangliomas (chemodectomas) can occur in the head or neck (see Chapter 19, XII).

I Nondental lesions of the jaw

Giant cell granuloma

Types. This jaw lesion can occur in two forms:

Central granulomas occur within the jaw.

Peripheral granulomas , occurring on the gingival or alveolar mucosa, are four times more common.

Characteristics. The mucosa is generally intact, but radiographs of the central lesions show radiolucent areas.

Treatment. Excision or curettage is the treatment of choice.

Fibrous dysplasia of the jaw is noted early in life.

Characteristics

It shows active growth in childhood and stabilization in adulthood.

Enlargement of the bone is the most common sign and may be either minor or significant enough to cause obvious facial asymmetry.

The maxilla is more commonly involved than the mandible.

Radiographs reveal sclerosis, lytic lesions, or unilocular lesions.

Treatment

Obvious deformity, pain, or interference with function suggests the need for surgery.

Malignant transformation is possible but uncommon, and conservative resection appears to be the best treatment.

Torus is a benign bony growth, occurring at the midline of the palate (maxillary torus) or bilaterally lingual to the bicuspid (mandibular torus). Tori grow slowly and generally have no significance except that they may interfere with the fitting of dentures.

Osteomas are slow -growing, benign tumors in the sinuses, jaws, or external ear canals. They may require excision if they produce a headache or an occlusion of drainage.

J Laryngeal lesions

Laryngocele is a dilatation of the laryngeal saccule, producing an air sac that communicates with the laryngeal ventricle. Anything that increases intralaryngeal pressure increases the size of a laryngocele (e.g., coughing, straining, playing a wind instrument). A laryngopyocele is an infected laryngocele. It can be fatal if it results in asphyxia or if the purulent contents are aspirated into the tracheobronchial tree.

Anatomy. Laryngoceles may be unilateral or bilateral. They may also be internal (within the larynx), external (presenting in the neck), or both (combined).

An internal laryngocele causes bulging of the false cord and aryepiglottic fold.

An external laryngocele appears as a neck swelling at about the level of the hyoid bone and anterior to the sternocleidomastoid.

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Characteristics

Internal laryngoceles cause hoarseness, breathlessness, and stridor on enlargement.

External laryngoceles increase in size with coughing or the Valsalva maneuver.

They are tympanic to percussion.

A hissing may be heard as the laryngocele empties air into the larynx when the air pressure is reduced.

Diagnosis

Plain films may show cystic spaces that contain air.

Tomograms may help to demonstrate the continuity between the internal and external components.

CT and MRI scans show these lesions well.

Treatment

Symptomatic laryngoceles are treated by surgical excision.

Laryngopyoceles should be treated by incision, drainage, and subsequent excision. Antibiotics

are also appropriate.

Laryngeal webs

Characteristics

They may be congenital or may follow bilateral vocal fold trauma.

When extensive, they present with stridor, weak phonation, and feeding problems in infants.

Treatment. Excision or division is now generally the preferred treatment, and placement of a stent or keel is often required.

Vocal nodules

Anatomy. Vocal nodules are bilateral benign masses that usually occur at the junction of the anterior and middle thirds of the true vocal folds.

Etiology. They are associated with vocal abuse.

Treatment

Vocal nodules are best treated by modifying the patient's speaking or singing technique through voice therapy.

Surgery is rarely necessary and is generally performed only after failure of voice therapy.

Vocal polyps

Characteristics. Vocal polyps are usually unilateral and often do not regress with speech therapy— two important points in distinguishing the polyps from vocal nodules.

Treatment

The recommended therapy is careful excision with microscopic visualization and avoidance of injury to the underlying lamina propria.

In selected cases, the laser may be helpful.

Laryngeal granulomas

Anatomy. Laryngeal granulomas occur over the vocal processes of the arytenoid cartilages.

Etiology. They are generally the result of trauma, usually from an endotracheal tube, and are usually associated with reflux laryngitis. Voice abuse may be a factor.

Treatment

Antireflux therapy is often helpful.

They can regress as a result of treatment with antireflux medication and speech therapy.

Pulmonary involvement is rare.

It is commonly associated with the parotid or submandibular glands, but it is not isolated to these sites.

Fixation of overlying skin and sinus formation are common. Biopsy can lead to a chronically draining sinus tract.

Treatment is by surgical excision or curettage and drainage. Antimycobacterial drug therapy is not indicated.