Identifying and Diagnosing the Adult Neck Mass
to the editor: I read with pleasure the article, “The Adult Neck Mass,”1 in American Family Physician. I would like to add a few facts that family physicians might find useful.
In patients with thyroglossal cysts, a physical examination usually reveals a midline mass at or below the hyoid bone that moves with protrusion of the tongue and swallowing. As many as 62 percent of these ducts contain ectopic thyroid tissue.2 Other neck swellings moving with protrusion of the tongue include subhyoid bursitis and a plunging ranula.
Although rare, the carotid body tumor (chemodectoma), a lateral neck swelling, is the most common extra-adrenal paraganglioma. Examination reveals a rubbery, nontender mass at the level of the carotid bifurcation, along the anterior border of the sternomas-toid, more mobile laterally than vertically. Innervated by the glossopharyngeal nerve, it is poorly encapsulated. Many exhibit transmitted pulsations from the carotid vessels or, less commonly, expand themselves, reflecting their extreme vascularity. A bruit that disappears with carotid compression may be heard. Neurologic examination may reveal deficits of the lower cranial nerves. Most paragangliomas secrete catecholamines, although few patients become symptomatic.2 Metastatic disease, which occurs more frequently, dictates a thorough evaluation for head and neck primaries. Open and percutaneous biopsy should be avoided because of risk of hemorrhage. Duplex ultrasound, computed tomography, or carotid angiography is diagnostic; carotid angiography estimates the size of the tumor, bilaterality, possible involvement of the external and internal carotid arteries, and evaluation of primary atherosclerotic disease. Surgery with vascular reconstruction is the procedure of choice, although the low incidence of malignancy and the chronic nature of the tumor favor a more conservative approach in asymptomatic, elderly, or high-risk patients.
A pulsatile lateral neck swelling is the most common presentation of a carotid artery aneurysm; other symptoms include pain, transient ischemic attack, stroke, hoarseness, and dysphagia.3 A carotid duplex scan is confirmatory, although arteriography still remains the gold standard.
Branchial cysts manifest most commonly in persons 20 to 39 years of age. In patients older than 40 years, branchial cysts should be treated as malignant until proven otherwise.4 Consider the possibility of the branchio-otorenal syndrome, a distinct entity with branchial arch anomalies (e.g., cysts, sinuses, fistulas, auricular pits, deafness, cleft palate/uvula, renal anomalies).
Any cervical adenopathy should prompt an examination of the axillary, epitrochlear, mediastinal, external iliac, and inguinal chains. The presence of supraclavicular lymphadenopathy should focus on examination and possible imaging of the thorax, abdomen, and pelvis (breast, lung, liver, pancreas, gastrointestinal tract, genitalia) for primaries. The left supra-clavicular lymph node (Virchow's node) receives, through the thoracic duct, the lymph drainage below the diaphragm, thus reflecting infradiaphragmatic disease. Hodgkin's disease in children usually presents as asymptomatic cervical or supraclavicular lymphadenopathy, which may fluctuate over time.5 Two thirds of patients will have mediastinal adenopathy, which may produce symptoms of tracheal or bronchial compression.