What are the possible causes and treatments for a swollen lump on the neck?

Swollen Lump on Neck: Evaluation and Management

A swollen neck lump requires immediate risk stratification for malignancy based on specific clinical features, and you should NOT routinely prescribe antibiotics unless clear signs of bacterial infection are present, as this delays cancer diagnosis. 1, 2

Immediate Risk Assessment for Malignancy

Identify high-risk patients using these criteria:

• Duration and history: Mass present ≥2 weeks without significant fluctuation OR uncertain duration, with no history of recent infectious etiology 1, 2
• Physical examination red flags: Size >1.5 cm, firm consistency, fixed to adjacent tissues, ulceration of overlying skin, or nontender mass 1, 2
• Patient demographics: Age >40 years, tobacco use, alcohol use 2

Important caveat: A nontender neck mass is MORE suspicious for malignancy than a tender one 1

Differential Diagnosis by Cause

The three main categories are: 1, 3

• Malignant causes: Metastatic squamous cell carcinoma (most common), lymphoma, thyroid cancer, salivary gland tumors 3, 4
• Infectious causes: Cervical lymphadenitis, tuberculous lymphadenitis, cat-scratch disease, infectious mononucleosis 3
• Benign causes: Reactive lymphadenopathy, congenital lesions, normal anatomic structures (submandibular glands, hyoid bone, transverse process of C2, carotid bulb) 1

Management Algorithm for HIGH-RISK Patients

If the patient meets ANY high-risk criteria above, proceed immediately with: 1, 2

1. Order contrast-enhanced CT or MRI of the neck (strong recommendation) 1
2. Perform targeted physical examination including visualization of larynx, base of tongue, and pharynx using flexible laryngoscopy or mirror laryngoscopy 1
3. Obtain fine-needle aspiration (FNA) instead of open biopsy when diagnosis remains uncertain after imaging 1, 2
4. Educate the patient about increased malignancy risk and explain recommended diagnostic tests 1

Critical pitfall to avoid: Do NOT perform open biopsy before imaging and specialist evaluation, as this can seed tumor cells and worsen outcomes 2

Specific Examination Findings to Document

During physical examination, assess for: 1

• Oral cavity: Remove dentures, inspect all surfaces, palpate floor of mouth for ulcers or masses 1
• Oropharynx: Check for tonsil asymmetry, masses, or ulcers (ask patient to open mouth WITHOUT protruding tongue, as tongue protrusion obscures visualization) 1
• Skin examination: Look for asymmetry, border irregularity, color changes, diameter changes, or ulceration suggesting melanoma or cutaneous malignancy 1
• Associated symptoms: Ear pain with normal ear examination suggests referred pain from pharyngeal malignancy 1

Red Flag Symptoms Requiring Urgent Evaluation

Notify provider immediately if patient has: 1

• Difficulty or pain with swallowing 1
• Voice change or hoarseness 1
• Ear pain or hearing loss on same side as neck mass 1
• Unexplained weight loss 1
• Fever >101°F 1
• Mouth sores or tooth pain 1

Management for LOW-RISK Patients (No High-Risk Features)

If patient does NOT meet high-risk criteria: 1

• Advise weekly self-monitoring: Patient should check mass size weekly using fingertips 1
• Expected timeline: Infectious masses should resolve completely or return to much smaller size within 2-3 weeks 1
• Document follow-up plan: Ensure clear plan exists to assess resolution or obtain final diagnosis 1

Contact provider if: 1

• Mass gets larger
• Mass does not go away completely
• Mass goes away but returns

Special Consideration: Cystic Neck Masses

For patients >40 years with cystic neck masses (identified by FNA or imaging), continue evaluation until diagnosis is obtained—do NOT assume the mass is benign, as up to 80% may be malignant. 1, 2

Antibiotic Use: When and When NOT to Prescribe

Only prescribe antibiotics if BOTH local AND systemic signs of bacterial infection are present: 1

• Local signs: Warmth, erythema of overlying skin, localized swelling, tenderness to palpation 1
• Systemic signs: Fever, tachycardia, symptoms specific to head/neck infections (rhinorrhea, odynophagia, otalgia, dental pain) 1

If antibiotics are prescribed, inform patient: 1

• Expected time until lymph node returns to normal size (<1.5 cm)
• Need for clinical follow-up if mass persists

Critical point: Most neck masses in adults are neoplastic, NOT infectious—judicious antibiotic use prevents delayed cancer diagnosis, bacterial resistance, unnecessary costs, and adverse effects 1

Timeline for High-Risk Patients

Specialist referral and evaluation should occur within DAYS, not weeks. 2

Biopsy results should be available within 1 week; if not, patient should contact provider immediately. 2

When Diagnosis Remains Uncertain After FNA and Imaging

Recommend examination of upper aerodigestive tract under anesthesia (panendoscopy) BEFORE open biopsy for patients at increased risk for malignancy without identified diagnosis or primary site. 1