Neck mass

A neck mass is any palpable lump or swelling in the neck. It may arise from lymph nodes, salivary glands, thyroid, congenital remnants, vessels, muscle or soft tissue. The reasoning depends on age, tempo, location, associated symptoms and risk factors, and malignancy and deep neck infection must be identified without delay.

Clinical relevance. In adults over 40 years, a persistent neck mass is malignant until proved otherwise, most often a metastatic squamous cell carcinoma from the head and neck, or thyroid cancer or lymphoma. In children, most masses are inflammatory or congenital, and lymphoma is the main malignancy.

Anatomy. The sternocleidomastoid divides each side into anterior and posterior triangles, and the midline lies between the hyoid and the suprasternal notch. Lymph node levels I to VII drain defined regions of the head, neck and upper chest.

Mechanisms. Reactive hyperplasia, infection, neoplastic infiltration, developmental failure of embryonic structures, and vascular or glandular enlargement.

Classification by time course.

• Acute (days): reactive lymphadenitis, abscess, sialadenitis, deep neck space infection, Kawasaki disease.
• Subacute (weeks): tuberculous and atypical mycobacterial adenitis, cat scratch disease, infectious mononucleosis, toxoplasmosis, HIV, thyroiditis.
• Chronic (months to years): neoplasm, congenital cyst, goitre.

Key distinctions. A hard, fixed, painless, non-tender mass in an adult is cancer until proved otherwise. A mass that moves on swallowing is thyroid or thyroglossal, and one that moves on tongue protrusion is thyroglossal. A pulsatile mass is vascular.

History.

• Duration, change in size, pain, fever, night sweats, weight loss (over 10% in 6 months), fatigue and itching.
• Head and neck symptoms: sore throat, dysphagia, odynophagia, hoarseness, otalgia, nasal obstruction or bleeding, oral ulceration, hearing loss, haemoptysis and trismus.
• Tobacco (including smokeless), alcohol, betel nut, sexual history (oral human papillomavirus), occupational and radiation exposure, previous cancer, and family history of thyroid cancer or endocrine tumours.
• Infection risk: tuberculosis contact, HIV, animal scratches (cats), dental disease, travel, raw milk, and recent skin or scalp infection.
• Drugs: phenytoin and allopurinol cause lymphadenopathy.
• Age: age under 15 and over 40 alter probabilities.

Examination.

• Describe the mass by site (level and triangle), size in two dimensions, shape, consistency, mobility, fixity to skin or deep structures, tenderness, pulsation, fluctuance, transillumination and bruit, and whether it moves on swallowing or tongue protrusion.
• Examine all lymph node groups (cervical, supraclavicular, axillary, inguinal), spleen and liver.
• Head and neck: skin and scalp, oral cavity, tonsils, tongue base, floor of mouth, salivary glands (bimanual), thyroid, nose, ears, and flexible nasopharyngolaryngoscopy for the nasopharynx, larynx and hypopharynx.
• Cranial nerves, voice, stridor, airway patency and ability to swallow saliva.
• Chest, breast and abdomen when metastasis is possible.

Red flags.

• Stridor, voice change, drooling, trismus, inability to swallow saliva, or floor of mouth swelling (airway threat).
• Fever with neck stiffness, torticollis or rapidly spreading swelling (deep neck infection).
• Hard, fixed, painless node, or size over 2 cm persisting beyond 4 weeks.
• Supraclavicular node (Virchow node) or posterior triangle node.
• Age over 40 with tobacco and alcohol use.
• Weight loss, night sweats, fever (B symptoms) or generalised lymphadenopathy.
• Pulsatile or bruit bearing mass.
• Rapidly growing thyroid nodule, hoarseness or fixed thyroid mass.
• Cranial nerve palsy, ear pain with no ear disease, or unilateral serous otitis media in an adult (nasopharyngeal cancer).

Special groups. Children: most nodes are reactive, and size over 2 cm, persistence over 4 to 6 weeks, supraclavicular site, and hard texture indicate biopsy. Pregnancy: avoid radiation, use ultrasound and MRI without contrast. HIV: tuberculosis, lymphoma, Kaposi sarcoma and persistent generalised lymphadenopathy are likelier.

Midline.

• Thyroglossal duct cyst (moves with swallowing and tongue protrusion), dermoid cyst, thyroid nodule and goitre, thyroid cancer.
• Submental and submandibular nodes, ranula, lipoma, Ludwig angina.

Anterior triangle.

• Reactive and infective lymphadenopathy, abscess and deep neck space infection (parapharyngeal, retropharyngeal).
• Branchial cleft cyst, carotid body tumour (paraganglioma), carotid artery aneurysm, laryngocele.
• Metastatic squamous cell carcinoma (oral cavity, oropharynx, larynx, hypopharynx, nasopharynx), lymphoma (Hodgkin and non-Hodgkin), thyroid cancer nodal disease, salivary gland tumours.
• Sialadenitis, sialolithiasis, parotid and submandibular tumours.

Posterior triangle. Reactive nodes, metastatic nodes (nasopharynx, skin, lung, breast), lymphoma, cystic hygroma (lymphatic malformation), lipoma, cervical rib, pharyngeal pouch (Zenker diverticulum), subclavian aneurysm, Pancoast tumour.

Systemic or infective adenopathy. Infectious mononucleosis, cytomegalovirus, HIV, tuberculous lymphadenitis (scrofula), nontuberculous mycobacterial infection, cat scratch disease, toxoplasmosis, syphilis, brucellosis, tularaemia, Kawasaki disease, Kikuchi disease, sarcoidosis, systemic lupus erythematosus, rheumatoid arthritis, drug reaction.

Haematological and metastatic. Hodgkin lymphoma, non-Hodgkin lymphoma, leukaemia, Castleman disease, metastasis from lung, breast, gastrointestinal tract, kidney, melanoma and skin cancers, Kaposi sarcoma.

Other. Lipoma, sebaceous cyst, neurofibroma, schwannoma, vascular malformation, haemangioma, fibromatosis, hyoid bursa, thyroiditis.

Step 1. Secure the airway if threatened. Assess the tempo, site and risk profile to separate infective, inflammatory, congenital and neoplastic causes.

Step 2. First line tests for a persistent mass or suspected infection: full blood count with film (atypical lymphocytes, blasts), CRP and ESR, liver tests, LDH, urea, creatinine, HIV test, and TSH for thyroid disease. Heterophile antibody or EBV serology for suspected mononucleosis, and Bartonella, toxoplasma and syphilis serology depending on exposure. Tuberculosis testing (interferon gamma release assay or tuberculin skin test, with limited use in endemic areas, and chest radiograph).

Step 3. Imaging.

• Ultrasound of the neck is the first test: it distinguishes solid and cystic masses, identifies abnormal nodes (round, loss of fatty hilum, short to long axis ratio over 0.5, peripheral or chaotic vascularity, calcification, cystic change), and directs sampling.
• CT neck and chest with contrast for staging, deep infection (rim enhancing collection, airway), and abnormal nodes; MRI for nasopharynx, skull base and soft tissue characterisation; PET CT for unknown primary and lymphoma.
• CT angiography or Doppler for suspected vascular masses (never biopsy a pulsatile mass).

Step 4. Tissue.

• Ultrasound directed fine needle aspiration (cytology, flow cytometry, cell block, and culture and tuberculosis tests) for a node or thyroid nodule; core needle biopsy preferred for suspected lymphoma.
• Thyroid nodules: TSH, ultrasound risk stratification, and fine needle aspiration reported by Bethesda category (I non-diagnostic, II benign, III atypia of uncertain significance, IV follicular neoplasm, V suspicious, VI malignant).
• Excisional biopsy of a whole node when lymphoma is suspected and core biopsy is inadequate, and open biopsy only after imaging and endoscopy have not found a primary (avoid open biopsy of a suspected squamous carcinoma node, because it seeds tumour).
• Panendoscopy with directed biopsies and tonsillectomy (or tongue base mucosectomy) for squamous cell carcinoma of unknown primary. Human papillomavirus (p16) and EBV testing of the node.

Limitations. Fine needle aspiration of a cystic node can be falsely negative because of necrosis, and lymphoma may not be diagnosed on cytology alone. Negative tuberculosis skin or blood tests do not exclude disease in HIV. CT and MRI cannot separate reactive from malignant nodes with certainty by size alone.

Immediate priorities. Secure the airway and obtain senior ENT and anaesthetic help for stridor, drooling, trismus or floor of mouth swelling. Give oxygen, keep the patient upright, and avoid sedatives and lying flat.

Deep neck infection or abscess.

• Ampicillin with sulbactam 3 g IV every 6 hours (maximum 12 g daily; every 12 hours for CrCl 15 to 29 mL/min; every 24 hours under 15 mL/min), or ceftriaxone 2 g IV once daily (maximum 4 g daily) plus metronidazole 500 mg IV every 8 hours (maximum 1.5 g daily); monitor creatinine, full blood count and clinical response at 48 hours.
• Penicillin allergy: clindamycin 600 to 900 mg IV every 8 hours (maximum 2.7 g daily; monitor for diarrhoea and Clostridioides difficile infection).
• Surgical or image directed drainage of any collection, with cultures. Dexamethasone 8 to 10 mg IV once to reduce airway oedema may be used (evidence is limited). Change to oral therapy when improving, and complete 10 to 14 days in total.

Reactive or infective lymphadenitis (low risk node, under 2 cm, tender, recent infection). Observe for 2 to 4 weeks. Treat the source (dental or throat infection). For bacterial lymphadenitis, flucloxacillin 500 mg to 1 g orally every 6 hours for 7 to 10 days (maximum 4 g daily; reduce the dose in severe kidney impairment), or clindamycin 300 to 450 mg orally every 6 to 8 hours (maximum 1.8 g daily) if penicillin allergic. Biopsy if there is no resolution at 4 to 6 weeks.

Tuberculous lymphadenitis. Treat through the tuberculosis service: isoniazid 5 mg/kg orally daily (maximum 300 mg), rifampicin 10 mg/kg daily (maximum 600 mg), pyrazinamide 25 mg/kg daily (maximum 2 g) and ethambutol 15 mg/kg daily (maximum 1.6 g) for 2 months, then isoniazid and rifampicin for 4 months; pyridoxine 10 to 25 mg daily; monitor liver tests at baseline and at 2 and 4 weeks, visual acuity, and uric acid; adjust doses in kidney impairment; do not excise the node. Paradoxical enlargement during treatment is common and does not mean failure.

Thyroid nodule. Management follows risk stratification and cytology (repeat aspiration, surveillance, lobectomy or thyroidectomy). Treat hyperthyroidism or hypothyroidism as indicated.

Malignancy suspected or confirmed.

• Refer urgently (within 2 weeks) to head and neck, haematology or endocrine surgery teams before any open surgical biopsy.
• Do not start corticosteroids before a tissue diagnosis when lymphoma is possible, because they can obscure histology.
• Complete staging by CT or PET CT, and discuss at the multidisciplinary meeting.

Vascular masses. Do not biopsy. Refer to vascular surgery after CT angiography or MR angiography for carotid aneurysm or paraganglioma.

Congenital cysts (thyroglossal, branchial, dermoid, lymphatic malformation). Elective surgical excision after imaging, with the Sistrunk procedure (including the central hyoid) for thyroglossal duct cysts. Treat any infection first.

Analgesia. Paracetamol 1 g orally or IV every 6 hours (maximum 4 g daily; 3 g daily if weight under 50 kg, malnutrition, alcohol excess or liver disease). Avoid NSAIDs when bleeding or kidney injury is a risk. Monitoring. Review airway, temperature and swelling every 4 to 6 hours in deep infection. Repeat ultrasound if there is no improvement in 48 to 72 hours. Follow reactive nodes at 2 to 4 weeks and 6 weeks.

Referral and escalation. ENT (head and neck) for any persistent mass over 3 weeks, any red flag, or unknown primary. Haematology for suspected lymphoma. Endocrine surgery for thyroid cancer.

Vascular surgery for aneurysm. Infectious diseases for tuberculosis or HIV related adenopathy.

Paediatric surgery for children with congenital cysts.

Admission criteria. Airway compromise, deep neck infection, sepsis, inability to swallow, rapidly growing mass, planned urgent biopsy and staging in a frail patient.

Discharge and safety netting. Discharge low risk patients with a review in 2 to 4 weeks. Patients return for stridor, voice change, difficulty swallowing, fever, rapid growth, bleeding, or if the mass has not resolved by 4 to 6 weeks.