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Approximately 95% of thymic cysts are unilateral, and 90% of thymic ectopias are cystic.

They are generally found in children, and there is a male predominance.

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TABLE 18-2 Congenital Neck Masses

They may be unilocular or multilocular.

Loculated cysts generally contain amber to brown fluid, which may be clear or turbid.

Complications

Cysts are often asymptomatic but may be painful if they are infected or if they grow suddenly. Midline cysts may cause dysphagia.

Both benign and malignant hyperplasia have been reported in these cysts.

Myasthenia gravis is not found in association with cervical thymic cysts.

Differential diagnosis

Branchial cleft cysts seldom extend inferiorly to the clavicle and often present with signs of acute inflammation.

Cystic hygromas are lateral, spongy, and more diffuse. They are seen generally in infants.

Treatment. Surgery is the treatment of choice.

Parathyroid cysts

Characteristics

These unusual cysts generally present in adults from 30–50 years of age as a solitary mass at either inferior pole of the thyroid gland.

Tracheal deviation is usual and causes a variable degree of respiratory obstruction.

Hoarseness may occur because of pressure on the recurrent laryngeal nerve.

Treatment consists of surgical excision.

B Lesions of thyroid origin

Overview. The thyroid gland originates at the foramen cecum and descends centrally to the thyroid and cricoid cartilages.

The thyroglossal duct may pass in front of, through, or behind the hyoid bone. It is generally obliterated but may persist.

Elements of thyroidal primordium may remain at any site in its passage.

These elements may give rise not only to cysts and fistulas but also to accessory thyroid tissue and neoplasms.

Most cystic remnants occur in the midline around the hyoid bone.

Solid tumors of thyroglossal duct origin occur almost exclusively within the tongue and above the hyoid bone.

Thyroid rests

Characteristics

Thyroid rests may be lingual or may occur in the neck.

Endotracheal ectopias may occur.

Palpation of the normal position of the thyroid often reveals easily palpable tracheal rings in patients with these rests.

Treatment is dictated by the degree of obstruction present and by the presence of other thyroid tissue.

A thyroid scan should be performed before the removal of lesions suspected of being thyroid rests to ensure that there is functional thyroid tissue in the usual location.

Between 70% and 80% of patients have no other functional thyroid.

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Thyroglossal cysts, sinuses, and fistulas

Anatomy

These occur in the midline, unless previous surgery has produced distortion.

Approximately 20% are suprahyoid, 15% occur at the hyoid, and 65% are infrahyoid.

Characteristics

Fistulas are almost always the result of infection with spontaneous or surgical drainage. Fistulas can drain internally, externally, or both (complete fistulas).

Thyroglossal duct cysts present by age 10 in 50% of cases.

There is no sexual predominance, but there is a racial predominance; the cysts occur most often in whites.

Cysts usually measure 2–4 cm in diameter and gradually increase in size, although the size may fluctuate.

They rise and fall with the larynx during swallowing.

Treatment is total surgical excision (Sistrunk procedure), including the:

Cyst and sinus to the base of the tongue

Whole fistula if one is present

Middle third of the hyoid bone

C

Cutaneous branchiogenic cysts are rare, asymptomatic nodules that are noted soon after birth and gradually increase in size.

Anatomy. They are located in the suprasternal notch.

Treatment is by local surgical excision.

D

Teratomas are growths that consist of multiple tissues that are foreign to the part of the body in which they arise.

Types

Epidermoid cysts, the most common type, are lined by squamous epithelium and have no adnexa.

Dermoid cysts are epithelium-lined cavities containing skin appendages (e.g., hair, glandular tissue, and follicles).

Teratoid cysts are lined with simple stratified squamous epithelium or respiratory epithelium and contain cheesy keratinous material. They are rare in the head and neck.

Cervical teratomas are most commonly present at birth. Appearance after the age of 1 year is rare.

Characteristics

The lesions are usually 5–12 cm in their long axis and are semicystic, although they may be solid. They are usually unilateral.

Infants with cervical dermoids usually have stridor, apnea, or cyanosis because of tracheal compression or deviation. Dysphagia may also be present.

Some infants are asymptomatic at birth but become symptomatic within weeks or months.

Associated anomalies. There is an increased incidence of maternal hydramnios, but affected infants show no increase in associated anomalies.

Treatment. Early excision in infants is mandatory.

Malignant teratomas of the neck are rare and occur exclusively in adults. The prognosis is very poor.

Nasal dermoids are often apparent shortly after birth.

Anatomy. The nasal dorsum is the most common site, but they may occur in the tip of the nose or the columella.

Characteristics

They show a male predominance of 2:1.

They must be differentiated from encephaloceles and gliomas.

Treatment. Early removal is important. Recurrences secondary to incomplete removal are common.

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E Vascular tumors

(see Chapter 26, II B 3 a)

Hemangiomas are the most common tumors of the head and neck in children. Girls are more often affected than boys, and the lesions are usually solitary.

Types

Capillary hemangiomas, such as nevus flammeus (port-wine stain) and strawberry nevus are characteristically found in the dermis.

They rarely appear in adults.

They have an early period of evolution, after which they often regress. They may develop suddenly and grow quite large.

Cavernous hemangiomas are more permanent. Spontaneous regression is more likely for hemangiomas present at birth than in those appearing later.

Arteriovenous hemangiomas occur almost exclusively in adults and have a predilection for the lips and perioral skin.

Invasive hemangiomas occur in the deep subcutaneous tissues, deep fascial layers, and muscles.

These hemangiomas present as neck masses, predominantly in children.

They tend to recur long after excision but do not metastasize.

The masseter and trapezius are the muscles most commonly involved in the head and neck.

Intramuscular hemangiomas most commonly present in young adults as palpable, mobile, noncompressible masses.

They are generally without thrills, pulsations, or bruits.

Pain secondary to compression of other structures is usually present.

Subglottic hemangiomas are usually capillary in type. Owing to their location, they often present at birth (or soon thereafter) with stridor and usually with cutaneous involvement as well.

Treatment

Congenital cutaneous hemangiomas are generally not treated initially.

When patients reach school age, cosmetically deforming lesions may be excised.

Steroids may be used to slow a rapid growth phase if necessary.

Tunable dye and copper vapor lasers have shown promise in the treatment of cutaneous lesions.

Subglottic lesions may require tracheotomy, steroids, and, in some cases, laser excision. Surgery may be needed for extensive lesions.

Radiation therapy has been used to suppress tumor growth. However, radiation alone will not effect a cure, and its use in these lesions is controversial.

Cystic hygromas are found predominantly in the neck and are usually noted at birth or soon thereafter.

Anatomy. They are more common in the posterior triangle.

They may reach up into the cheek or parotid region and down into the mediastinum or axilla.

Large masses extend past the sternocleidomastoid muscle into the anterior compartment and may cross the midline.

They may involve the floor of the mouth and the base of the tongue.

Symptoms and signs may include:

Difficulty in nursing

Facial or neck distortion

Respiratory distress

Brachial plexus compression with pain or hyperesthesia

A sudden increase in size secondary to spontaneous hemorrhage, which can be fatal

Characteristics

There is no predilection for either sex or for either side of the body.

The hygromas can be progressive, static, or regressive.

Small lesions are unilocular and firm.

Large tumors are loculated, shiftable, and compressible.

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The hygromas generally transilluminate.

The cyst walls are usually tense, and because the loculi tend to communicate, rupture of one locule can cause all of them to partially collapse.

Treatment. Surgery is the mainstay of treatment.

Recurrences are common because the cysts insinuate themselves into adjacent structures, so resection is often incomplete.

The greater the lymphangiomatous component of a hygroma, the more likely it is to recur.

Oral and perioral lymphangiomas are relatively common lesions that are usually found at birth or soon thereafter. They behave very much like cystic hygromas.

F Branchial cleft anomalies

Embryology

In the fourth week of gestation, five ridges appear on the ventrolateral surface of the embryonic head, with a groove between each. These ridges and grooves form the branchial arches and clefts, respectively.

The pharyngeal pouches develop internally at the same level as the external grooves.

Types

A sinus , or incomplete fistula , has either an internal or an external opening.

A complete fistula has both an internal and an external opening.

A cyst has neither an internal nor an external opening.

Combinations of any of the preceding types can occur.

Anatomy. Branchial cleft anomalies are generally located along the anterior border of the sternocleidomastoid muscle or deep to it. They can occur anywhere between the external auditory canal and the clavicle.

First branchial cleft anomalies are always superior to the hyoid bone.

If a fistula is present, it courses superiorly to end near the external auditory canal.

The cyst and tract may lie in the parotid gland, with a variable relationship to the facial nerve.

Second cleft anomalies are the most common type.

An external opening, when present, is about two thirds of the way down the sternocleidomastoid anteriorly.

The fistula, if present, ascends with the carotid sheath and crosses over the hypoglossal and glossopharyngeal nerves and between the external and internal carotid arteries to end at the tonsillar fossa.

Third cleft anomalies are rare.

The external opening occurs in the same position as in a second cleft fistula.

The tract ascends along the carotid sheath posteriorly to the internal carotid artery, over the hypoglossal nerve, under the glossopharyngeal nerve, and over the vagus nerve to open in the piriform sinus.

Fourth branchial cleft anomalies have never been seen in their entirety.

Theoretically, they would have an external opening anterior to the sternocleidomastoid muscle in the lower neck.

They would descend along the carotid sheath into the chest, passing under the subclavian artery on the right and the aortic arch on the left, ascend into the neck to cross the hypoglossal nerve, then descend to open into the esophagus.

Characteristics

Branchial cleft cysts are generally smooth, round, nontender masses.

An increase in size during upper respiratory infections is common.

An infected branchial cleft cyst may abscess or rupture spontaneously to form a sinus.

The size and the location of a branchial cleft anomaly determine the symptoms.

Large cysts may cause dysphagia, stridor, and dyspnea.

Small cysts are often not discovered until adulthood because of their slow rate of growth and minor symptoms.

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Treatment

Complete excision without damage to the surrounding vital structures is the definitive treatment. Antibiotics are given if the lesion is infected.

Incision and drainage are avoided, if possible, because they make subsequent excision more difficult.

G

Encephaloceles are congenital brain herniations, which may be confused with nasal dermoids or polyps. Meningitis or cerebrospinal fluid leaks are not uncommon, particularly with manipulation.

Anatomy

They are usually discovered early in life. Approximately 75% are occipital, 15% are sincipital, and 10% enter the nose or nasopharynx.

These lesions may or may not communicate centrally. Communicating lesions increase in size and tension when the infant cries; noncommunicating ones generally do not.

Treatment should include total removal. The lesions do not need to be treated as emergencies if there is no imminent threat of meningitis.

IV Acquired Lesions

A

Leukoplakia and keratosis are white lesions that occur on the mucosa of the mouth, pharynx, or larynx. Erythroplakia is a similar red patch.

Etiology. These lesions are associated with repeated trauma (e.g., from poorly fitting dentures, decayed teeth), smoking, or use of alcohol. There is little correlation between the clinical appearance of the lesions and their histology. Erythroplakia is somewhat more likely to be carcinoma.

Diagnosis. Biopsy, to rule out squamous cell carcinoma, should be performed:

In high-risk patients (smokers and drinkers)

If the lesion persists after the removal of an irritative focus

Treatment. Benign leukoplakic lesions require no treatment but do require continued observation.

B Papillomas

Squamous papillomas of the oral cavity usually occur singly but may be multiple. They are common on the palate and faucial arches.

They are usually pedunculated and cauliflowerlike in appearance.

Recurrence is rare after excision.

Nasal papillomas

Squamous papillomas of the nasal cavity are warts that are similar in appearance and behavior to cutaneous warts elsewhere on the body.

Cylindrical and fungiform papillomas are other forms of benign nasal papillomas.

Inverted papillomas

Anatomy

The lesions typically arise from the lateral nasal wall and can invade the sinuses and orbits.

Grossly, the lesions appear bulky and deep red to gray in color. They vary in consistency.

Unlike nasal polyps of allergic origin (see IV C), they are unilateral.

Characteristics

Patients generally present with nasal obstruction, a postnasal drip, and headaches. A few have epistaxis. These lesions occur mainly in men between 50 and 70 years of age.

The reported incidence of malignant degeneration is about 2%. The incidence of associated malignancy in adjacent tissue is as high as 15%.

Treatment is complete excision. Recurrence is common because excision is often incomplete.

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Laryngeal papillomas are the most common laryngeal tumors of childhood and may be found at any age.

Juvenile type. This type occurs predominantly in childhood and tends to involute at puberty.

Etiology. The etiology is viral.

Characteristics

Multiple papillomas are the most common characteristic. They may involve the airway from the epiglottis to the bronchi. The vocal folds are usually involved.

Hoarseness is an early sign, and obstruction is a later one.

Treatment

A tracheotomy may be necessary but should be avoided if possible because it predisposes to tracheal seeding of the papillomas.

Laryngoscopic removal, often by the use of a carbon dioxide laser, is the mainstay of therapy.