Evaluating Neck Masses in Adults
James Haynes, MD; Kelly R. Arnold, MD; Christina Aguirre-Oskins, MD; And Sathish Chandra, MD
- Neck masses are often seen in clinical practice, and the clinician should be able to determine the etiology of a mass using organized, efficient diagnostic methods.
- The first goal is to determine if the mass is malignant or benign; malignancies are more common in adult smokers older than 40 years.
- Etiologies can be grouped according to whether the onset/duration is acute (e.g., infectious), subacute (e.g., squamous cell carcinoma), or chronic (e.g., thyroid), and further narrowed by patient demographics.
- If the history and physical examination do not find an obvious cause, imaging and surgical tools are helpful. Contrast-enhanced computed tomography is the initial diagnostic test of choice in adults.
- Computed tomography angiography is recommended over magnetic resonance angiography for the evaluation of pulsatile neck masses.
- If imaging rules out involvement of underlying vital structures, a fine-needle aspiration biopsy can be performed, providing diagnostic information via cytology, Gram stain, and bacterial and acid-fast bacilli cultures.
ACUTE NECK MASSES
- By far, the most common cause of cervical lymphadenopathy is infection or inflammation created by an array of odontogenic, salivary, viral, and bacterial etiologies. These lymph nodes are often swollen, tender, and mobile, and can be erythematous and warm.
- Upper respiratory symptoms caused by common viruses usually last for one to two weeks, whereas lymphadenopathy generally subsides within three to six weeks after symptom resolution. 2
- Biopsy is appropriate if an abnormal node has not resolved after four to six weeks, and should be performed promptly in patients with other findings suggestive of malignancy.
- Bacterial infections of the head and neck predominantly cause cervical lymphadenopathy. Lymphadenopathy caused by Staphylococcus aureus or group A beta Streptococcus has no predictable sites of lymph node inflammation.
- Common antibiotics used for lymphadenopathy include firstgeneration cephalosporins, amoxicillin/ clavulanate (Augmentin), or clindamycin.
- The extra-pulmonary form of Mycobacterium tuberculosis infection causes a cervical lymphadenopathy. The diffuse, bilateral lymph nodes are characteristically multiple, fixed, firm, non-tender masses located in the posterior triangle/cervical chain. 1
- A negative result on purified protein derivative testing does not rule out atypical mycobacterial infections, which also should be considered.
- A fine-needle aspiration biopsy (FNAB) of the lymph nodes or referral to a head and neck surgeon may be warranted if the lymphadenopathy persists after initial diagnosis and treatment.
- Inflammation of salivary glands (acute sialadenitis) commonly occurs in older, debilitated persons in the setting of dehydration or recent dental procedures. 1
- Affected salivary glands cause rapid or gradual onset of pain and swelling, possibly with local edema, erythema, and tenderness or fluctuance consistent with an abscess.
- Bimanual compression toward the duct opening may expel purulent discharge into the oral cavity. Neck CT with intravenous contrast media may be warranted to confirm this diagnosis and rule out other contributing etiologies such as a dental abscess or local tumor compression. 1
SUBACUTE NECK MASSES
- Subacute masses are noticed within weeks to months. A persistent asymptomatic neck mass in an adult should be considered malignant until proven otherwise. 6
- Squamous cell carcinomas of the upper aerodigestive tract are the most common primary neoplasms of the head and neck, and their metastases are often the source of cervical lymphadenopathy of unknown origin. 8
- Common presenting symptoms include nonhealing ulcers, dysarthria, dysphagia, odynophagia, loose or misaligned teeth, globus, hoarseness, hemoptysis, and oropharyngeal paresthesias. 8 Lymph nodes associated with malignancy are usually firm, fixed, and matted.
- A subset of squamous cell carcinomas with increasing prevalence includes those related to human papillomavirus infection (especially high-risk human papillomavirus 16). 9, 10
- These lesions present with rapidly enlarging, lateral, cystic lymph nodes; persistent cervical nodal hypertrophy; palatine or lingual tonsillar asymmetry; dysphagia; voice changes; or pharyngeal bleeding.10
- The initial diagnostic test of choice in an adult with a persistent neck mass is contrast-enhanced CT, 20 which provides valuable initial information regarding the size, extent, location, and content or consistency of the mass. Contrast media may help identify malignant lymph nodes that are not enlarged and distinguish vessels from lymph nodes. 20
- When ultrasonography is indicated instead of or in addition to CT, it is useful to distinguish cystic from solid lesions, detect nodal size, and differentiate high-flow from low-flow vascular malformations. 20
- CT angiography is recommended for evaluating a pulsatile neck mass and is preferred over magnetic resonance angiography (MRA). 20 CT, MRA, and PET with CT are all useful in the evaluation of patients after cancer treatment.
- The clinician may proceed with FNAB, if indicated, once appropriate imaging has ruled out involvement of underlying vital structures. FNAB can provide further information through cytology, Gram stain, and bacterial and acid-fast bacilli cultures while avoiding complications of open biopsy.
- Patients with suspected infectious and inflammatory masses should be tested for HIV, Epstein-Barr virus, cytomegalovirus, toxoplasmosis, tuberculosis, and B. henselae, when clinically appropriate.