What diagnostic tests are recommended for a patient presenting with neck enlargement?

Diagnostic Testing for Neck Enlargement

For patients with neck enlargement at increased risk for malignancy, order CT neck with contrast (or MRI with contrast) as the primary imaging modality, followed by fine-needle aspiration (FNA) if the diagnosis remains uncertain after imaging. 1

Risk Stratification First

Before ordering any tests, determine if the patient is at increased risk for malignancy based on these criteria: 1

High-risk history features:

• Mass present ≥2 weeks without significant fluctuation 1
• Mass of uncertain duration 1
• No history of infectious etiology 1
• Age >40 years with tobacco or alcohol use 2
• Associated symptoms: hoarseness, dysphagia, odynophagia, otalgia, unexplained weight loss 2

High-risk physical examination features:

• Firm consistency 1
• Size >1.5 cm 1
• Fixation to adjacent tissues 1
• Ulceration of overlying skin 1

Diagnostic Algorithm for High-Risk Patients

Step 1: Targeted Physical Examination

Perform or refer for visualization of the larynx, base of tongue, and pharynx—not just external palpation. 1, 2 This requires laryngoscopy to identify potential primary mucosal sites.

Step 2: Imaging (Strong Recommendation)

Order CT neck with contrast as the mandatory first imaging study. 1 MRI with contrast is an acceptable alternative. 1 The American Academy of Otolaryngology-Head and Neck Surgery emphasizes that contrast is essential unless contraindicated (severe renal insufficiency or contrast allergy), as it significantly improves mass characterization, delineates lesion borders, and identifies potential primary sites. 3, 2

Key imaging specifications to include in your order: 3

• Specify anatomical location precisely (e.g., "left neck mass at level III")
• Request "with intravenous contrast" explicitly
• Include clinical details: duration, size, consistency, associated symptoms
• Request post-contrast T1-weighted sequences if ordering MRI
• Request multiple planes (axial, sagittal, coronal)

Step 3: Fine-Needle Aspiration (Strong Recommendation)

If diagnosis remains uncertain after imaging, perform FNA rather than open biopsy. 1 FNA is preferred because open biopsy disrupts tissue planes and complicates subsequent surgery if malignancy is present. 2

Step 4: Ancillary Tests

If no diagnosis after FNA and imaging, obtain additional tests based on clinical context (e.g., EBV serology, HIV testing, tuberculosis testing). 1

Step 5: Examination Under Anesthesia

Before proceeding to open biopsy, perform examination of the upper aerodigestive tract under anesthesia with panendoscopy to identify occult primary sites. 1, 2

Management of Low-Risk Patients

For patients without high-risk features, document a follow-up plan and educate them on warning signs that would trigger re-evaluation. 1 Imaging may be deferred in truly low-risk cases, but maintain a low threshold for advancing to the high-risk algorithm if the mass persists beyond 2-4 weeks.

Critical Pitfalls to Avoid

Do not prescribe empiric antibiotics without clear signs of bacterial infection (warmth, erythema, localized swelling, tenderness, fever). 1, 2 Most adult neck masses are neoplastic, not infectious, and antibiotics delay diagnosis of malignancy. 1

Do not assume cystic masses are benign. 1, 2 Cystic metastases are common in head and neck cancers, particularly from squamous cell carcinoma and papillary thyroid cancer. Continue evaluation until a definitive diagnosis is obtained. 1

Do not perform open biopsy before completing the full workup. 2 This disrupts tissue planes and significantly complicates subsequent definitive surgery if malignancy is present.

Do not order CT with and without contrast. 3 This doubles radiation exposure with minimal added diagnostic benefit.