Neck Mass: Causes, Warning Signs and Diagnosis

What counts as a neck mass

A neck mass can come from lymph nodes, the thyroid, the salivary glands, skin, fat, muscle, blood vessels or leftover tissue from development before birth. Doctors think about three things together: age, how long it has been there, and where it is.

A widely used rule is "7-7-7": a lump present for about 7 days is usually inflammatory, 7 months suggests a tumor, and 7 years suggests a congenital (present-from-birth) cause. It is a rough guide only.

Common causes of a neck mass

Swollen lymph nodes (most common)

The neck contains around 300 lymph nodes. They swell when they filter infection from the throat, tonsils, teeth, ears, scalp or skin. Reactive nodes are usually:

• soft or rubbery, mobile and often tender
• smaller than 1 to 1.5 cm
• on both sides, during or just after an infection
• gone or much smaller within 2 to 6 weeks

Infectious mononucleosis, strep throat, dental infections and scalp conditions are typical triggers. See swollen lymph nodes.

Infected lymph node (lymphadenitis)

A neck mass with redness, warmth and pain is usually lymphadenitis, a bacterial infection of a node, often from staph or strep. It is common in young children. It may soften as pus forms (an abscess) and need drainage. In children, a slow, purple, painless node can be caused by atypical mycobacteria, and cat scratches can cause cat-scratch disease.

Thyroid nodules and goiter

A lump in the lower front of the neck that moves up when you swallow is usually thyroid. Thyroid nodules are very common and over 90% are benign. An ultrasound and, if needed, a fine-needle biopsy decide which need treatment.

Salivary gland swelling

The parotid glands sit in front of the ears and the submandibular glands under the jaw. Swelling that gets worse when you eat, or with a bad taste in the mouth, suggests a salivary stone or infection (sialoadenitis). A slow, painless parotid lump is usually a benign tumor but still needs removal.

Congenital cysts

• Thyroglossal duct cyst: a midline lump that moves when you stick your tongue out. Common in children.
• Branchial cleft cyst: a smooth, soft lump on the side of the neck in front of the large sternocleidomastoid muscle, often noticed in a teenager or young adult after a cold. In adults over 40, a "cyst" in this location must be checked for cancer that has spread to a node.

Skin and fat lumps

Sebaceous (epidermoid) cysts and lipomas sit just under the skin and move with it or slide freely.

Serious causes

Head and neck cancer

Head and neck cancer of the mouth, throat, tonsils, voice box or nose often spreads first to the neck nodes. A painless, firm neck lump may be the only sign. HPV-related throat cancers are now common in non-smoking adults aged 40 to 60, often appearing as a cystic neck node. Warning signs that go with it:

• hoarseness for more than 3 weeks
• difficulty or pain swallowing
• ear pain on one side with a normal ear
• a mouth ulcer that will not heal
• coughing blood

Lymphoma

Lymphoma causes firm, rubbery, painless nodes that slowly enlarge, sometimes in several places. Fevers, drenching night sweats, weight loss and itching ("B symptoms") may come with it.

Thyroid cancer and metastatic cancer

A hard thyroid nodule that is fixed, growing, or comes with a hoarse voice needs prompt assessment. Nodes above the collarbone, especially on the left, can be the first sign of cancer in the chest or abdomen.

Neck mass by location

Features that help tell benign from worrying

How a neck mass is diagnosed

Guidelines from the American Academy of Otolaryngology advise that adults with a neck mass that has lasted 2 weeks or more, or that has worrying features, be assessed for cancer rather than given repeated courses of antibiotics.

1. History: duration, growth, infections, dental problems, smoking, alcohol, travel, animal exposure, TB contacts.
2. Examination: the lump, all neck nodes, the mouth, tonsils, thyroid and ears.
3. Throat examination: a thin flexible camera through the nose (nasendoscopy) to check the throat and voice box.
4. Ultrasound: the first test for most lumps, especially in children and for the thyroid.
5. Fine-needle aspiration (FNA) biopsy: a thin needle samples cells, usually guided by ultrasound.
6. CT or MRI with contrast: to map a mass and look for a hidden primary cancer. PET-CT in some cases.
7. Blood tests: blood count, mononucleosis test, thyroid function.

An open biopsy that cuts into a lump is usually avoided until cancer has been excluded or planned for, because it can complicate treatment.

Treatment

Treatment depends entirely on the cause:

• Reactive nodes: no treatment beyond managing the infection, and a check if they persist.
• Bacterial lymphadenitis: antibiotics, with drainage for an abscess.
• Salivary stones and infection: fluids, sour candies to stimulate saliva, warm massage, antibiotics, or stone removal.
• Congenital cysts: surgical removal, usually once any infection settles.
• Thyroid nodules: monitoring, or surgery if suspicious or causing pressure.
• Cancer and lymphoma: surgery, radiotherapy, chemotherapy or immunotherapy, planned by a specialist team.

Frequently asked questions

What causes a neck mass?

Most neck masses are lymph nodes swollen by an infection such as a cold, sore throat or tooth abscess. Other causes include thyroid nodules, salivary gland swelling, cysts present from birth, lipomas and skin cysts. In adults, cancers of the head and neck, lymphoma and thyroid cancer are less common but important causes.

What does a neck mass with redness mean?

A red, warm, tender neck lump usually means an infected lymph node (lymphadenitis) or an infected cyst or abscess. It often comes with fever. It needs medical assessment for antibiotics, and possible drainage if it becomes soft and fluctuant.

When should I worry about a lump in my neck?

See a doctor if an adult neck lump lasts more than 2 to 3 weeks, or is hard, painless, fixed or growing, or comes with hoarseness, trouble swallowing, ear pain, night sweats or weight loss. Get emergency help for breathing or swallowing difficulty.

Are cancerous neck lumps painful?

Usually not. Cancerous lymph nodes are typically painless, firm or hard and gradually enlarge. Painful lumps are more often infections. Pain does not rule out cancer, though, so duration and other features matter more.

How long do swollen neck nodes take to go down?

Nodes swollen by a viral infection usually shrink over 2 to 6 weeks, though a small, soft node can be felt for months. A node that keeps growing, becomes hard, or has not shrunk after 3 to 4 weeks should be checked.