Evaluation of Neck Masses

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[edit] Evaluation of Neck Masses

Fred G. Fedok

Michael Burnett

The differential diagnosis for a neck mass is extensive. The primary care physician should establish an orderly, streamlined approach based on historic and anatomic considerations to diagnose and treat neck masses. The history and physical examination provide the diagnosis for most neck masses and guide an expedient workup for the remainder.

[edit] ANATOMY AND AGE

An understanding of fundamental anatomic considerations can greatly simplify the diagnosis and treatment of a neck mass. Most neck masses fit into one of the following diagnostically salient locations: (1) midline: suggests thyroglossal duct cyst, dermoid, or teratoma; (2) anterior to the sternocleidomastoid muscle: suggests branchial cleft remnant anomalies; (3) associated with thyroid gland: suggests diffuse thyroid enlargement or thyroid nodule; (4) areas of major salivary glands (preauricular region or angle of the jaw): suggests pathology of the parotid or submandibular glands, including sialoadenitis vs. salivary neoplasms; and (5) routes containing clusters of lymph nodes: suggests inflammatory or neoplastic lymphadenopathy (Fig. 182-1).

Figure 182-1 Lymphatic drainage of external (left) and internal (right) areas of head and neck. Arrows indicate lymphatic drainage pathways. (From McGuirt FW. In Cummings CW, et al, editors:Otolaryngology: head and neck surgery, ed 2, St Louis, 1998, Mosby.)

Neck masses may be divided into three broad etiologic categories: congenital, inflammatory, and neoplastic (malignant or benign). The earliest branch point used in formulating a differential diagnosis, in order of probability, may be the patient's age. Regarding neck masses, patients can be grouped by age into children ages 15 and younger, young adults ages 16 to 40, and adults over 40. Statistically, there is a dramatic rearrangement in the order of likelihood of a given diagnosis based on these groupings. In children and young adults an inflammatory condition is the most likely etiology of a neck mass, with congenital masses second and neoplastic diagnoses least likely. In adults over 40, however, a persistent neck mass should be considered a malignant neoplasm, generally metastatic, until proven otherwise (Fig. 182-2).

Figure 182-2 Relative frequency of specific neck masses within causative groups by age. AT, Anterior; PT, posterior; M, midline; AIDS, acquired immunodeficiency syndrome. (From McGuirt FW. In Cummings CW, et al, editors: Otolaryngology: head and neck surgery, ed 3, St Louis, 1993, Mosby.)

[edit] PATIENT EVALUATION

[edit] History

The physician approaches the history of the neck mass as any other physical complaint. The physician determines when the mass was first noticed, what brought it to the patient's attention, and if the mass is progressively increasing in size or following a crescendo/decrescendo pattern of growth. Associated pain and discharge are noted, as well as constitutional symptoms such as fevers, weight loss, and night sweats. Any patient with a neck mass should be specifically questioned about the presence or absence of hoarseness or changes in voice, odynophagia, dysphagia, otalgia, decreased hearing or aural fullness, nasal fullness or discharge, cough, and hemoptysis. The patient reports any history of cancer or lesions removed from the head or neck, as well as any recent dental work, dental complaints, or upper respiratory tract infections. Relevant exposure history includes tuberculosis exposure during travel, animal exposures (e.g., cat or dog scratches), radiation exposure, and occupational exposures to substances implicated in head and neck cancer (e.g., nickel, woodworking). A family history of head and neck cancer might suggest one of the familial syndromes of endocrine neoplasia. Social history is extremely important, including tobacco and alcohol use, which are significant risk factors for head and neck carcinoma. If the mass is in the supraclavicular region, the pulmonary, gastrointestinal, and genitourinary systems are reviewed, with a history of mammograms and their results, since the supraclavicular node often represents a metastasis from a primary neoplasm below the clavicles.

[edit] Physical Examination

Any patient with a neck mass requires a thorough physical examination. The etiology of a neck mass in the adult involves a search for a primary site of disease in the head and neck that may have lead to either inflammatory or neoplastic change in a neck lymph node. Thus the head and neck examination must be methodic, not focusing solely on the mass.

The skin of the head and neck is examined for suspicious skin lesions. The ears are examined, including pneumatic otoscopy. A unilateral middle ear effusion might be a clue to a mass obstructing the eustachian tube orifice. The nasal mucosa is examined for lesions. The oral cavity and oropharynx are best examined using a head mirror or head light, thus freeing both hands to perform the examination. The palate, tonsils, tonsillar pillars, and posterior pharyngeal wall are examined. The tongue examination includes the lateral surfaces and underneath the tongue on the floor of the mouth, which are more likely to contain mucosal malignancies than the dorsum. The tongue and floor of mouth should be palpated in search of submucosal lesions, which would otherwise be missed. Bimanual examination can often better delineate and size discrete structures, including normal anatomy (e.g., submandibular glands) and pathologic masses. The gingiva is examined throughout the lingual and buccal surfaces. A mirror examination inspects the nasopharynx above and the larynx and hypopharynx below.

The mass is palpated for texture. Rock-hard masses are more typical of carcinoma, whereas fluctuance usually denotes a fluid-filled or pus-filled entity. A mass fixed to the overlying skin or deeper tissues might indicate invasion of the surrounding tissues. A mass that moves up and down on swallowing indicates tethering to either the strap muscles or tongue base, typically seen with thyroid-associated entities (e.g., thyroid nodule, thyroglossal duct cyst). Signs of inflammation include tenderness and overlying erythema and warmth. The position within the neck may suggest the primary site of pathology.

The remainder of the neck is palpated along the major lymph drainage routes for adenopathy (see Fig. 182-1). The thyroid gland is palpated for nodules, and the trachea's position is noted with respect to the midline. The cranial nerves should be specifically challenged for deficits.

A thorough head and neck examination often identifies the primary site of pathology, thereby guiding the remainder of the workup and treatment plan.

[edit] INFLAMMATORY NECK MASSES

[edit] Lymphadenopathy

Lymphadenopathy simply implies enlarged lymph nodes, without specifically indicating pathology or disease. Palpable lymph nodes are a common and frequently normal finding in children. About 50% of children have palpable lymph nodes 1 to 1.5 cm in size and not associated with obvious infection or systemic illness. Cervical lymphadenopathy should prompt a search for a primary site of head and neck pathology that may have caused the adenopathy. Odontogenic sources and pharyngitis are common etiologies. Lymphadenitis implies signs of inflammation of lymph nodes, including enlarged, tender, warm, erythematous nodes. Suppurative lymphadenitis further denotes purulent change within the lymph nodes. The varying etiologies for lymphadenitis generally have distinct patterns. Important differentiating characteristics in diagnosing the etiology of cervical lymphadenitis include acute vs. chronic presentation, number of nodes involved (single, unilateral, bilateral, generalized), signs of inflammation, fluctuance, associated head and neck or dental disease, exposure history, and age.

Acute cervical lymphadenitis is most often caused by regional or generalized viral infections. Seasonal viral upper respiratory tract infections (e.g., rhinovirus, adenovirus, enterovirus) are common causes. Herpes simplex virus (HSV) gingivostomatitis, roseola infantum (exanthema subitum, HSV-6), Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human immunodeficiency virus (HIV) are common etiologies of acute cervical lymphadenitis. With viral causes, enlarged lymph nodes are generally found bilaterally, frequently with signs of inflammation such as tenderness and overlying erythema and warmth, but without fluctuance. Often, concomitant constitutional symptoms can be elicited.

Acute suppurative lymphadenitis, in contrast, is typically a unilateral infection of bacterial origin. The involved nodes may be mildly tender and fluctuant, although otherwise not particularly inflamed. Group A β-hemolytic streptococci and Staphylococcus aureus are the most common organisms and may be primary infectors or may superinfect a viral lymphadenitis. As many as 25% of such infections involve anaerobes, with gram-negative organisms occasionally identified.^[1] Suppuration tends to occur within 2 weeks of symptom onset. Up to 40% of patients present with antecedent upper respiratory symptoms.^[2] Systemic signs and toxemia are uncommon unless there is an overlying cellulitis or clinically apparent primary focus of infection.

In chronic cervical lymphadenitis (longer than 3 weeks), viruses again are the most common etiologies, and patients typically present with bilaterally enlarged lymph nodes. When unilateral and fluctuant, lymphadenitis is usually of bacterial origin and should suggest bacteria found in acute suppurative lymphadenitis or in common granulomatous diseases (e.g., Mycobacterium tuberculosis, atypical mycobacteria, cat-scratch disease, toxoplasmosis).

[edit] Granulomatous Diseases

[edit] Mycobacteria.

Mycobacteria may cause chronic granulomatous lymphadenitis, typically within the nodal network of the major salivary glands. M. tuberculosis lymphadenitis occurs after spread from a primary pulmonary focus. Patients may have associated constitutional symptoms of weight loss, night sweats, or fevers, although their absence is not unusual. The diagnosis is strongly suggested by a positive response to purified protein derivative (PPD) skin testing. Treatment involves a full course of antituberculous medications.

Atypical mycobacteria are common colonizers in the mouths of children. They invade locally to cause infection, manifesting as a chronic, unilateral, firm mass in the submandibular or preauricular areas, generally in children younger than 5 years old and rarely after age 12. Atypical mycobacteria lymphadenitis does not respond to systemic medications; definitive therapy involves surgical excision. Incisional biopsy should be avoided because of the potential for persistently draining infections. Diagnosis of mycobacterial infection may be made on acid-fast staining or culture of an aspirated specimen, although the yield on culture may be less than 60%.^[3] Approximately 50% of patients with atypical mycobacteria infection will mount a weak response to a PPD skin test.

[edit] Cat-scratch Disease.

Cat-scratch disease represents another granulomatous lymphadenitis. The putative causative organism is Bartonella henselae. The typical patient presents with tender lymphadenopathy in the head and neck, particularly in the regions of the parotid and submandibular glands, developing within 2 weeks after a cat scratch. The primary site of inoculation often manifests a skin lesion such as a pustule. Approximately 75% of patients are able to recall an antecedent cat scratch, with another 15% reporting exposure to a cat.^[4] In a small percentage of patients canine exposure is responsible. Needle aspiration yields sterile pus. A cat-scratch disease skin test is available. The majority of cases will resolve without treatment in 2 to 3 months. Symptoms include fever and usually are mild in immunocompetent patients. Treatment is generally supportive, with antipyretics and analgesics as needed. More severe cases can be treated with erythromycin or doxycycline.

[edit] Toxoplasmosis.

Toxoplasmosis is caused by the organism Toxoplasma gondii, usually carried by a domestic cat host. It is typically transmitted to humans through eating infected food products. Although immunocompromised patients are at risk for the more severe disseminated forms of the disease, immunocompetent patients are more likely to develop only mild symptoms, including lymphadenopathy, particularly in the head and neck. The diagnosis can be ascertained through acute and convalescent titers. Effective treatment is provided by a course of pyrimethamine and trisulfapyrimidine, which is especially important in immunocompromised hosts and pregnant women. In the otherwise healthy adult the infection is usually self-limited.

[edit] Actinomyces.

Poor oral hygiene and mucosal trauma are risk factors for Actinomyces infections, as are diabetes and impaired immune function. Infection with these organisms typically manifests as a painless, indurated neck mass, which may mimic a neoplasm. This is not a lymphadenitis, and the infection usually does not cause lymphadenopathy. The diagnosis is made by needle aspirate to identify characteristic sulfur granules, which represent conglomerations of organisms. The infections can reach the skin surface to cause chronic, draining cutaneous fistulas. Treatment is with high-dose penicillin, since no penicillin resistance has been identified to date.

[edit] Miscellaneous Infections.

Other, less common infectious causes of cervical lymphadenitis include secondary syphilis, a sexually transmitted disease caused by the spirochete Treponema pallidum; brucellosis, which may be acquired by drinking infected unpasteurized milk; and Lyme disease, caused by the organism Borrelia burgdorferi, through inoculation by a bite from the carrier tick Ixodes dammini, endemic to many regions in the northeastern and midwestern United States.

[edit] Salivary Gland Origin

[edit] Sialolithiasis.

Sialolithiasis, or calculi within the system of salivary gland ducts, is principally a disease of the submandibular gland (90% of cases), although it can occur in the parotid or minor salivary glands.^[5] The majority of submandibular sialoliths are radiopaque, whereas this applies to only a minority of parotid calculi. Stones may be revealed because of recurrent swelling and pain that may be exacerbated by superimposed infection. The diagnosis may be made by bimanual palpation, plain radiographs, sialography, or computed tomography (CT) scan. Transoral removal of an obstructing stone may be accomplished if the stone is situated near the duct orifice. Recurrent symptoms caused by salivary calculi may require surgical excision of the involved salivary gland.

[edit] Acute Suppurative Sialoadenitis.

Acute suppurative infection can affect the parotid, submandibular, or sublingual salivary glands, although the most common scenario is an acute parotitis. The typical patient is an adult, over age 50, generally with one or more reasons for decreased salivary secretions and poor oral hygiene. Volume depletion from any cause, debilitation leading to decreased fluid intake, and medications with anticholinergic side effects are factors that reduce the flow of saliva through the salivary ducts, allowing for retrograde infection of the salivary gland. A common scenario is in the postoperative setting. The usual symptom complex is acute onset of pain and swelling of the affected salivary gland, often associated with fevers or other constitutional symptoms. Examination reveals a swollen, tender gland with overlying erythema. A few patients present with bilateral parotid involvement. Regional adenopathy may be noted. Suppurative parotitis rarely impairs facial nerve function, and such a finding suggests an alternative or concomitant diagnosis, including malignancy. The physician should assess for pus at the orifice of the parotid duct, found opposite the upper second molar, or at the submandibular duct orifice, found adjacent to the frenulum of the tongue. A discharge sample, if obtainable, can be sent for Gram's stain and culture. The most common offending organism is S. aureus, although streptococci, and occasionally gram-negative or anaerobic organisms, can be cultured.

Treatment consists of (1) empiric antibiotics to cover β-lactamase-resistant S. aureus; (2) measures to improve salivary flow, including sialogogues (e.g., lemon drops); (3) volume repletion; and (4) cessation of anticholinergic medications, if possible. Analgesics and warm compresses alleviate pain. If tolerated by the patient, manually “milking” the affected salivary gland may assist with drainage and resolution of the infection. If no significant improvement is noted after 2 to 3 days of therapy, a CT scan may be considered to rule out abscess, mass lesion, or impacted sialolith, all of which may require surgical intervention. Sialography is specifically contraindicated in the setting of acute infection. In the patient with recurrent acute episodes or unresolving infection, a consult with an otolaryngologist is indicated.

[edit] Acute Nonsuppurative Sialoadenitis.

Acute nonsuppurative sialoadenitis (sialadenitis) is typically a viral infection, the most common cause of which is mumps, although EBV, coxsackievirus, HIV, and other viruses may also involve the salivary glands. Mumps typically presents in children, manifesting as a viral syndrome with fevers, arthralgias, malaise, and parotid swelling, which is frequently bilateral. Treatment is generally supportive, although steroids or gamma globulin may be given to patients with severe disease. Parotid swelling usually resolves within 2 weeks.

[edit] Human Immunodeficiency Virus.

Patients with HIV infection may develop multiple lymphoepithelial cysts within the major salivary glands, especially the parotid gland, which may become infected. Parotid enlargement is usually diffuse and symmetric. Asymmetric rapid enlargement of a salivary gland in HIV patients suggests a need to rule out lymphoma.

[edit] Miscellaneous Masses.

Noninflammatory painless swellings of the salivary glands, especially the parotid gland, can be seen with nutritional deficiencies, alcoholism, anorexia or bulimia, and endocrinopathies (e.g., diabetes). Sjögren's disease is an autoimmune disorder frequently characterized by nontender swelling of the parotid glands and less often the submandibular glands. It may be a primary disease or associated with a systemic collagen vascular disease. Diagnosis is often made with a biopsy of a minor salivary gland of the lip, revealing a lymphocytic infiltrate.

[edit] Thyroid Masses

Thyroid masses make up a large percentage of anterior neck masses (Box 182-1). The differential diagnosis includes parathyroid tumors and several congenital neck masses (see later section). Enlarged thyroid glands or palpable thyroid nodules are common findings in clinical practice; 6.4% of women and 1.5% of men in the Framingham Study had palpable thyroid nodules. An even greater percentage of patients have thyroid nodules when imaging studies are employed.

Clues to the diagnosis that a mass either represents or is associated with the thyroid gland include identifying its paratracheal position, palpating its intimacy with identifiable thyroid tissue, appreciating a bilaterality to the mass, and observing it move vertically with swallowing. The nature of the mass can often be identified with further testing, including radiologic imaging, generally ultrasound or CT scan.

Goiter refers to an enlarged thyroid gland. Iodine deficiency is uncommon in the United States but is the most common cause of goiter worldwide, called endemic goiter. In the United States the most common cause of goiter is the autoimmune disorder, Hashimoto's thyroiditis. Thyroid masses must be categorized both functionally and anatomically. Functionally, thyroid masses are labeled as toxic or nontoxic, based on whether an excess of thyroid hormone is released. Anatomically, a thyroid mass is categorized as displaying diffuse, multinodular or uninodular enlargement of the gland. To narrow the differential diagnosis further, the enlarged thyroid is classified as painful or painless. Pain suggests an inflammatory thyroiditis, hemorrhage into an existing cyst or nodule, or a rapidly expanding thyroid malignancy.

Along with a history of the mass itself, its onset, rate of growth and associated local symptoms, the history should include eliciting signs and symptoms of hypofunctioning or hyperfunctioning of the gland. Cold intolerance, lethargy, constipation, a deep voice, and cool dry skin suggest hypothyroidism. In contrast, heat intolerance, irritability, diarrhea, tachycardia, diaphoresis, and weight loss suggest hyperthyroidism. Prior radiation exposure, extremes of age (children, elderly), and associated hoarseness are all associated with increased risk of a thyroid mass being malignant.

The thyroid gland is best evaluated with the examiner standing behind the patient and reaching around each side to palpate the gland, felt just adjacent to the trachea, from approximately the level of the laryngeal cartilages to just above the level of the thoracic inlet. When the patient swallows, the thyroid sweeps under the examining fingers in the vertical dimension. More prominent thyroid glands are obvious on visual inspection. The examiner should search for signs of inflammatory enlargement of the gland, such as tenderness and overlying erythema.

Before ordering further laboratory or imaging studies, the physician should know what the test will reveal and how the results will affect the treatment plan. In assessing a patient with a neck mass of thyroid origin, the physician should (1) determine any functional thyroid abnormality resulting in altered hormone levels, (2) diagnose malignancies, and (3) evaluate local compressive symptoms or cosmetic disturbances. Thyroid-stimulating hormone (TSH) is the most effective screening test for thyroid functioning, with a full set of thyroid function tests for patients with an abnormal TSH. Approximately 5% to 10% of solitary nodules or dominant nodules in a multinodular goiter are malignant.^[6][7] No imaging study is sensitive or specific enough to diagnose or rule out malignancy. In contrast, fine-needle aspiration (FNA) biopsy is a safe and reliable means to assess for malignancy. In a large review of 18,000 FNA biopsies, 70% of patients were diagnosed with benign thyroid conditions, 4% with malignancy, and the remainder with indeterminate, nondiagnostic, or suspicious findings.^[8] If the initial biopsy is negative, repeating the biopsy improves the diagnostic yield by 50%. The false-positive and false-negative rates are less than 5%.^[8][7] The results of FNA biopsy can be used to guide a treatment plan, either observation for benign biopsies or referral and possible surgery for biopsies positive or suggestive of malignancy or for indeterminate biopsies. With simple cysts, FNA can even be therapeutic, with the nodule vanishing after aspiration.

Ultrasound or CT scan is best used to determine if the mass is truly thyroid in origin rather than distinguish a malignant vs. nonmalignant etiology. A thyroid nuclear uptake scan helps determine whether a hyperthyroid state is caused by a toxic multinodular goiter, functioning adenoma, or release of thyroid hormone from inflammation. The test may also have a role in treatment planning for the patient with a nondiagnostic FNA biopsy. If the nodule is hyperfunctioning (“hot nodule”) on nuclear uptake scan, it is unlikely to be malignant, and often the patient can be safely observed. The lack of uptake of nuclear tracer (“cold nodule”), however, is not sufficiently predictive for malignancy to be useful in clinical decision making.

[edit] NEOPLASTIC NECK MASSES

Head and neck cancers make up approximately 5% of new cancers diagnosed annually in the United States.^[9] In adults over age 40 a neck mass that persists for more than 4 weeks must be considered malignant until proved otherwise. The workup begins with a detailed history and physical examination; the physician should not rush to obtain excisional or incisional biopsies, since both are associated with an increased rate of local recurrence for most types of head and neck cancer. Rather, the physician searches for a potential primary site of cancer. A patient with a mass suspicious for head and neck cancer should be referred to an otolaryngologist.

If a suspected site for the primary lesion is identified, the lesion is biopsied. CT scan or magnetic resonance imaging (MRI) from skull base to thoracic inlet is obtained to explore the extent of the tumor and assess for occult metastases in the neck. A chest radiograph is an effective screen for pulmonary metastases. FNA biopsy of a neck mass can be obtained to confirm a diagnosis of malignancy. In contrast to excisional or incisional biopsies, FNA is not associated with increased rates of tumor recurrence, although FNA is much less capable of making a diagnosis of lymphoma. A suspected diagnosis of lymphoma is one of the few indications for an excisional lymph node biopsy in an adult. If a supraclavicular lymph node is involved, a mammogram for women and evaluation of the gastrointestinal and genitourinary tracts must be considered. If the primary site remains occult, the patient undergoes direct laryngoscopy, bronchoscopy, esophagoscopy, and nasopharyngoscopy, with appropriate random biopsies to find a primary site.

The treatment of head and neck cancer is site specific and depends on appropriate staging. As with other cancers, treatment modalities include surgery, with or without adjuvant radiation or chemotherapy, and primary radiation with or without chemotherapy. For children, in contrast to adults, only 10% of neck masses prove to be malignant. Thus the workup is more likely to focus initially on inflammatory and congenital etiologies of neck masses (see Chapter 183 ).

[edit] CONGENITAL NECK MASSES

In children and young adults, neck masses of congenital origin are second only to inflammatory neck masses in frequency of occurrence. The two most common categories of congenital neck masses are branchial cleft cysts and thyroglossal duct cysts, each of which constitutes about one third of congenital neck masses. Most congenital neck masses are recognized by the third decade of life.

[edit] Branchial Cleft Cysts

The branchial apparatus consists of five paired arches in the lateral wall of the embryo foregut, separated by invaginations called clefts. This system of arches and clefts normally gives rise to the varying components of the head and neck, and the arches and clefts themselves are obliterated in the process. Remnants of these embryologic precursors may persist, however, and result in cysts, sinuses, and fistulas. These lesions appear most often along the anterior border of the sternocleidomastoid muscle or in the periauricular region. Branchial cysts are blind pouches that may open to the skin or internally into the aerodigestive tract. In contrast, branchial fistulas extend all the way from skin to the aerodigestive tract. Branchial cleft abnormalities typically become evident in childhood or early adulthood, presenting as nontender, fluctuant masses. They may contain rests of lymphoid tissue and may become inflamed in the setting of an upper respiratory tract infection. Superinfection can occur, requiring treatment with broad-spectrum antibiotics. Definitive therapy requires complete surgical excision, ranging from minimal to extensive surgical dissection, depending on the extent of the tract involved. Diagnosis is supplemented by radiologic imaging, which may include CT scan and fistulogram.

[edit] Thyroglossal Duct Cysts

Thyroglossal duct cysts represent remnants of the thyroid's descent from the foramen cecum at the base of tongue to its final position in the neck. These embryologic remnants are cysts, not sinuses or fistulas, and do not drain to the outside spontaneously. They typically present as an asymptomatic neck mass in the midline near the hyoid bone. As with branchial cleft cysts, they can rapidly enlarge in the setting of infection. Effective surgical treatment, which minimizes chance for recurrence, requires excising the entire tract of thyroid descent, including the center portion of the hyoid bone. Before a suspected thyroglossal duct cyst is excised, the physician must ensure that the mass does not represent ectopic thyroid tissue, which is frequently the only thyroid tissue in the neck.

[edit] Vascular Anomalies

Hemangiomas and vascular malformations represent different pathologies, as determined by their cellular features and clinical behavior. Hemangiomas represent endothelial proliferation at abnormally rapid rates causing a vascular tumor. They are usually first noted in the immediate postnatal period, not at birth, with nearly all hemangiomas apparent by 6 months of age. Most undergo spontaneous regression over the first several years of life. Occasionally they require treatment with steroids, interferon-α, or surgical excision if they result in significant disability, as with aerodigestive tract compressive symptoms.

Unlike hemangiomas, vascular malformations are present at birth and typically grow at a rate commensurate with the child's overall growth. These may be capillary, venous, or lymphatic subtypes or a combination. Vascular malformations can be triggered into a rapidly accelerated growth phase by infection, trauma, or hormonal changes. When disfiguring or causing local compressive symptoms, they may require surgical excision.

[edit] Teratomas and Dermoid Cysts

Teratomas and dermoid cysts arise from rests of pluripotential cells, which persist from embryogenesis. They always occur in the midline of the neck, typically as painless masses. Dermoid cysts are attached to and move with the skin. This distinguishes them from thyroglossal duct cysts, which are also found in the midline but which move vertically underneath the skin with swallowing. In contrast to dermoid cysts, which are composed of two of the three germ layers, teratomas are composed of all three germ layers and therefore can give rise to any type of differentiated tissues, even hair or teeth.

[edit] Laryngocele

Laryngocele is an abnormal outpouching from the larynx, arising from the space between the true and false vocal cords known as the ventricle. This outpouching can pierce through the thyrohyoid membrane to reach the lateral neck. Activities such as glass blowing or trumpet playing, which cause prolonged increases in intralaryngeal pressure, can predispose to laryngoceles. The patient can often make the neck mass more apparent by performing maneuvers that increase laryngeal pressures. The diagnosis can be made on plain x-ray film, which shows an air-filled pouch. These lesions can be surgically excised.

[edit] REFERENCES