Neck masses are extremely common among children.
The most common cause of neck mass in children is
A lymph node may enlarge for the following reasons:
There is an infection nearby, for example, in the throat.
There is a general infection of the body (such as mononucleosis Infectious Mononucleosis Epstein-Barr virus causes a number of diseases, including infectious mononucleosis. The virus is spread through kissing. Symptoms vary, but the most common are extreme fatigue, fever, sore throat... read more
, tuberculosis Tuberculosis (TB) Tuberculosis is a chronic contagious infection caused by the airborne bacteria Mycobacterium tuberculosis. It usually affects the lungs, but almost any organ can be involved. Tuberculosis... read more 
, or human immunodeficiency virus Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and is treated with antiretroviral medications. If untreated, it can cause... read more 
[HIV]).
Other causes of neck masses include a cyst (a fluid-filled sac) that has been present from birth but is noticed only after it has become inflamed or infected. Neck masses may also result from swelling due to a neck injury, inflammation of the salivary glands, or noncancerous (benign) tumors. Sometimes, enlargement of the thyroid gland (called a goiter Congenital Goiter Congenital goiter is enlargement of the thyroid gland that is present at birth. The enlarged thyroid gland may produce too much thyroid hormone ( hyperthyroidism), too little thyroid hormone... read more ) may cause a neck mass. Rarely, lymphoma Overview of Lymphoma Lymphomas are cancers of lymphocytes, which reside in the lymphatic system and in blood-forming organs. Lymphomas are cancers of a specific type of white blood cells known as lymphocytes. These... read more 
, a thyroid tumor Thyroid Cancer The cause of thyroid cancer is not known, but the thyroid gland is very sensitive to radiation, which may cause cancerous changes. Thyroid cancer is more common among people who were treated... read more , or another cancerous (malignant) tumor is the cause.
Most neck masses cause no symptoms and are of greater concern to parents than to the children who have them. However, infected lymph nodes or cysts are tender and painful and may cause a fever.
Diagnosis of Neck Masses in Children
Imaging tests, swabs, blood tests, and tuberculosis skin tests
Thyroid tests
Biopsy
Because many neck masses are caused by viral infections and disappear without treatment, tests are usually not needed unless a mass lasts for several weeks.
However, doctors may take a swab from the back of the throat to test for a bacterial infection, or they may do blood tests to look for such disorders as infectious mononucleosis Infectious Mononucleosis Epstein-Barr virus causes a number of diseases, including infectious mononucleosis. The virus is spread through kissing. Symptoms vary, but the most common are extreme fatigue, fever, sore throat... read more , leukemia Overview of Leukemia Leukemias are cancers of white blood cells or of cells that develop into white blood cells. White blood cells develop from stem cells in the bone marrow. Sometimes the development goes awry... read more , hyperthyroidism Hyperthyroidism Hyperthyroidism is overactivity of the thyroid gland that leads to high levels of thyroid hormones and speeding up of vital body functions. Graves disease is the most common cause of hyperthyroidism... read more 
, or bleeding problems.
Doctors may also take x-rays Plain X-Rays X-rays are high-energy radiation waves that can penetrate most substances (to varying degrees). In very low doses, x-rays are used to produce images that help doctors diagnose disease. In high... read more of the chest and use computed tomography Computed Tomography (CT) In computed tomography (CT), which used to be called computed axial tomography (CAT), an x-ray source and x-ray detector rotate around a person. In modern scanners, the x-ray detector usually... read more 
(CT) or magnetic resonance imaging Magnetic Resonance Imaging (MRI) In magnetic resonance imaging (MRI), a strong magnetic field and very high frequency radio waves are used to produce highly detailed images. MRI does not use x-rays and is usually very safe... read more 
(MRI) of the head and neck to determine whether the mass is a tumor or a cyst and to determine more precisely how big it is and to where it extends. Ultrasonography Ultrasonography Ultrasonography uses high-frequency sound (ultrasound) waves to produce images of internal organs and other tissues. A device called a transducer converts electrical current into sound waves... read more 
may be done to determine whether a mass in the neck is a cyst.
A skin test for tuberculosis Screening Tests for Tuberculosis Tuberculosis is a chronic contagious infection caused by the airborne bacteria Mycobacterium tuberculosis. It usually affects the lungs, but almost any organ can be involved. Tuberculosis... read more may be done.
A piece of the mass may be removed and examined (biopsy) to determine whether a cancerous tumor is present.
A thyroid scan Thyroid ultrasound The thyroid is a small gland, measuring about 2 inches (5 centimeters) across, that lies just under the skin below the Adam’s apple in the neck. The two halves (lobes) of the gland are connected... read more and tests that determine how the thyroid is functioning Thyroid function tests The thyroid is a small gland, measuring about 2 inches (5 centimeters) across, that lies just under the skin below the Adam’s apple in the neck. The two halves (lobes) of the gland are connected... read more may be done.
Other tests, such as use of viewing tubes to examine the nose, throat, and larynx (called nasopharyngolaryngoscopy); lungs (bronchoscopy Bronchoscopy Bronchoscopy is a direct visual examination of the voice box (larynx) and airways through a viewing tube (a bronchoscope). A bronchoscope has a camera at the end that allows a doctor to look... read more 
); or esophagus (esophagoscopy Endoscopy Endoscopy is an examination of internal structures using a flexible viewing tube (endoscope). In addition to examinations, doctors can use endoscopy to do biopsies and give treatment. Endoscopes... read more ) may be needed.
Treatment of Neck Masses in Children
Depends on the cause
Treatment of neck masses depends on the cause. Antibiotics are useful for infected lymph nodes and other bacterial infections. If infection is not the cause, surgery may be needed.
Masses caused by viral infections and swelling due to injury gradually disappear with time.
Tumors and cysts usually require surgery.
