The first step towards the right treatment is to determine whether a lump noticed in the neck is a congenital cyst, an enlarged lymph node or another kind of lesion. The diagnostic process begins with a detailed history and examination, and is completed, when needed, with imaging and needle sampling. This page describes, in order, the diagnostic steps you may encounter.
History and examination
The doctor first asks when the lump was noticed, whether it grows and shrinks, how it relates to infections, and whether there is pain or discharge. On examination, the position of the lump is the most important clue:
- Side of the neck, below the angle of the jaw: A branchial cleft cyst comes to mind.
- Midline, around the hyoid bone, moving on swallowing: A thyroglossal duct cyst is considered.
- Midline, under the chin or in the floor of the mouth, immobile: A dermoid cyst becomes the leading possibility.
The consistency of the lump, its mobility, whether it is attached to the skin and its tenderness are also assessed. The inside of the mouth, the throat and, when necessary, the upper airway are examined with a thin camera (endoscope).
Ultrasound
Neck ultrasound is a painless and quick method that involves no radiation; it is usually the first imaging requested. It shows whether the lump is a fluid-filled cyst or a solid mass, the structure of its wall, its internal content and its relationship with neighbouring vessels. In people thought to have a thyroglossal duct cyst, the same examination confirms that the thyroid gland is in its normal position and healthy.
Further imaging
Magnetic resonance imaging (MRI) or computed tomography (CT) may be requested to show the deep extensions of the cyst, whether there is a tract running towards the throat, and its relationship with the large vessels and nerves. These examinations are particularly valuable for surgical planning; they allow the approach and the extent of the operation to be seen in advance. When a sinus or fistula is present, special views may be taken to show the course of the tract.
Fine-needle aspiration biopsy
In doubtful cases, particularly in adults, a sample of cells is taken from the lump with a fine needle. The procedure is usually performed under ultrasound guidance, as an outpatient and within a few minutes. The sample helps to distinguish whether the lump is a congenital cyst or another kind of lesion. Because a needle biopsy does not remove the cyst wall, it is not a treatment on its own.
Why is more caution taken in adults?
Congenital cysts can appear at any age; however, in adults, and particularly at older ages, a cystic mass on the side of the neck can also arise from other causes. For this reason, in adults the diagnosis is usually made by weighing ultrasound, further imaging and needle biopsy together; the definitive answer comes from the pathological examination performed after the cyst is removed.
When should you see a doctor?
- If you have noticed a lump in your neck that has not gone away for a few weeks
- If the lump is growing, hardening or has started to hurt
- If the lump is accompanied by hoarseness, difficulty swallowing or weight loss
- If there is an opening onto the skin that leaks
Frequently asked questions
Is every lump in the neck a cyst?
No. Enlarged lymph nodes, lesions arising from the salivary glands or thyroid, and other masses can also cause a lump in the neck. The distinction is made by the doctor through examination and imaging.
Is ultrasound enough for the diagnosis?
In most cysts, ultrasound shows the cystic structure. Further imaging and needle biopsy may be added for surgical planning or in doubtful cases.
Is a needle biopsy painful?
The procedure is done with a fine needle, takes a short time and is usually guided by ultrasound. Apart from a slight pricking sensation, no significant pain is expected.
This page is general information. Decisions about diagnosis and treatment are made for you personally, and only after an examination. If you have symptoms, see a doctor.