Causes of a Lump on the Back of the Neck

A lump on the back of the neck, like most lumps on your body, can be caused by a wide range of issues. While the lump may be a symptom of a serious health problem like cancer, most lumps on the back of the neck are harmless.

It's fairly easy to find a lump on the back of the neck during daily bathing and dressing, even if you can't see it. While many harmless lumps improve on their own, treatments that align with the cause of the lump can reduce symptoms and promote healing. This can be key to avoiding complications when the lump is serious.

This article describes the symptoms and likely causes of a lump behind the neck. It also covers risk factors and when to seek tests or treatment for your symptoms.

person holding back of neck

Cavan Images / Getty Images

Symptoms of a Lump on the Back of the Neck

Symptoms of a lump on the back of the neck can vary by person, the exact location of the lump, and its underlying cause. Other physical changes can also accompany the appearance of a lump in the back of the neck. This is often the case when the lump is linked with more serious causes, like an infection or cancer.

With causes ranging from harmless to serious, you may have any of the following symptoms with a lump in the back of the neck:

Causes of a Lump on the Back of the Neck

There are many causes of a lump in the back of the neck. Some of the most common reasons include the following:

Enlarged cervical lymph node: Cervical lymph nodes are located in the back and sides of your neck. These bean-shaped organs that are part of your body's immune system filter foreign substances and produce cells that fight infections. Lymph nodes can become swollen due to an infection or other inflammatory disease. When these problems occur, the lymph nodes produce more white blood cells to fight the foreign substance, which causes the affected area to swell.

Benign lumps, such as:

  • Nodular acne: Nodular acne is the most severe type of inflammatory acne. It is characterized by intense redness, inflammation, deep nodules, and cysts.
  • Skin boil: A skin boil, also known as a furuncle, occurs when a bacterial infection affects a hair follicle and the surrounding tissue. This swollen follicle usually is sore or painful to the touch. It is often filled with pus and has a pus-filled white or yellow head.
  • Epidermoid cyst: An epidermoid cyst usually develops as a noncancerous, slow-growing bump under the skin. It may have an enlarged pore in the center. It can occur when the skin cells shed from the outermost layer move under the skin rather than shedding. It can also occur when a hair follicle becomes clogged.
  • Lipoma: A lipoma usually occurs as a painless growth under your skin. It comprises adipose (fat) tissue surrounded by a thin capsule, usually not attached to any nearby muscle. It is usually soft, rubbery, and movable with gentle pushing.
  • Muscle knot: A muscle knot is a hard, sensitive knot of muscles that can cause pain when touched. It can occur due to muscle injury, overuse, stress, or tilting your head forward too long.

What Medications Can Cause a Lump on the Back of the Neck?

A lump on the back of your neck is not a known side effect of a specific medication. However, it can develop as an allergic reaction to an over-the-counter (OTC) or prescribed medication. It can also develop as a reaction to the following:

How to Treat a Lump on the Back of the Neck

The treatment used for a lump in the back of the neck varies based on the cause and stage of the problem. It can also differ based on your age, symptoms, and other medical conditions.

A benign lump in the back of the neck may be treated with one of the following types of therapy to manage symptoms until the underlying problem resolves:

A malignant lump on the back of the neck may be treated with one or more of the following therapies to kill cancer cells and prevent its spread:

  • Neck surgery Neck surgery is usually reserved for removing tumors and may be combined with other treatments to ensure that all cancer cells are killed.
  • Radiation therapy: Radiation therapy uses high-powered waves to shrink or destroy tumors by targeting the genetic material inside cancer cells and killing them.
  • Chemotherapy: Chemotherapy uses oral or injectable drugs to kill cancer cells.
  • Immunotherapy: Immunotherapy uses human-made antibodies to boost your immune system to identify better and destroy cancer cells.
  • Targeted drug therapy: Targeted drug therapy uses medications that interfere with the pathway that causes cancer cells to grow. These drugs vary based on the type of proteins targeted. 

Complications and Risk Factors Associated With a Lump on the Back of the Neck

Most lumps on the back of the neck don't cause harm. While they may be annoying, these lumps are typically benign. However, they can sometimes indicate a more serious condition like an infection or cancer.

When a lump in the back of the neck persists and remains untreated, it can lead to the following complications:

  • Sepsis (spread of untreated bacterial infection through your bloodstream)
  • Growth and metastasis (spread) of cancer

Cancer occurs when the genes that regulate cell production and growth are damaged or mutated. You have a greater chance of developing a cancerous lump on the back of the neck if you have any of the risk factors:

Are There Tests to Diagnose the Cause of a Lump on the Back of the Neck?

Tests to diagnose the cause of a lump in the back of the neck are important for identifying the cause and starting treatment of serious conditions as early as possible.

Your healthcare provider will likely perform a physical exam that includes questions about the severity and duration of your symptoms, your medical history, and your family history of diseases.

Based on the data gathered during your physical exam, your healthcare provider may use one or more of the following tests to diagnose a lump in the back of the neck:

Blood tests: A complete blood count (CBC) and other blood tests can measure the number of red blood cells, white blood cells, and platelets. Identifying certain enzymes or cancer markers can also indicate a lymphoma diagnosis.

Imaging tests:

Biopsies: biopsy removes a tissue sample for laboratory evaluation to diagnose a lump in the back of the neck. One of the following types of biopsies may be used:

  • Fine needle aspiration biopsy (FNA): A fine needle aspiration biopsy is often regarded as the best initial test to diagnose a lump in the neck. It involves extracting tissue by inserting a very thin needle into the lump.
  • Core needle biopsy: A core needle biopsy uses a larger needle to extract a piece of tissue from a lump in the neck.
  • Excisional biopsy: An excisional biopsy is when the entire lump is removed and evaluated.

When to See a Healthcare Provider

A lump on the back of the neck is usually not a symptom of a serious condition. A swollen lymph node is the most common cause of a lump on the back of the neck. However, it can be difficult to determine whether the problem needs treatment.

Contact your healthcare provider if you have any of the following symptoms with a lump on the back of the neck:

  • A lump that doesn't go away or improve after two to three weeks
  • A lump that increases in size
  • A lump that feels hard when you apply pressure
  • Irregularly shaped lump
  • Unexplained bruising
  • Difficulty breathing
  • Night sweats
  • Dysphagia (difficulty swallowing)
  • Fatigue
  • Unexplained weight loss


A lump on the back of the neck is a somewhat common problem. It can be caused by many issues, ranging from a clogged hair follicle to cancer. Most cases of a lump in the back of the neck do not present a cause for concern.

It is hard to know whether a lump on the back of the neck is a severe symptom. Getting a diagnosis as early as possible can help you find the reason for the lump.

A benign lump in the back of your neck may resolve on its own without treatment. Over-the-counter therapies like ointments and NSAIDs may be all you need to improve symptoms until the lump goes away. For more severe lumps, early treatment can help prevent the spread of disease or cancer, which can be a life-threatening issue.

14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Ramadas AA, Jose R, Varma B, Chandy ML. Cervical lymphadenopathy: Unwinding the hidden truth. Dent Res J (Isfahan). 2017;14(1):73-78.

  2. Newman MD, Bowe WP, Heughebaert C, Shalita AR. Therapeutic considerations for severe nodular acne. Am J Clin Dermatol. 2011 Feb 1;12(1):7-14. doi:10.2165/11532280-000000000-00000

  3. Ibler KS, Kromann CB. Recurrent furunculosis - challenges and management: a reviewClin Cosmet Investig Dermatol. 2014;7:59-64. doi:10.2147/CCID.S35302

  4. Cedars-Sinai. Epidermoid cysts of the skin.

  5. American Academy of Orthopaedic Surgeons. Lipoma.

  6. UWHealth. Bringing release to 'knotty' muscles.

  7. Prasad R, Arthur LG. Cervical lymphadenopathyFundamentals of Pediatric Surgery. Published online July 28, 2010:213-219. doi:10.1007/978-1-4419-6643-8_28

  8. Institute for Quality and Efficiency in Health Care (IQWiG). Boils and carbuncles: how are boils treated?

  9. American Academy of Dermatology Association. Acne clinical guideline.

  10. Cedars Sinai. Epidermoid cysts of the skin.

  11. Hayward WA, Sibbitt WL, Sibbitt RR, et al. Intralesional injection of triamcinolone acetonide for subcutaneous lipoma causing musculoskeletal and neurologic symptoms. J Clin Aesthet Dermatol. 2018;11(5):38-42.

  12. Memorial Sloan Kettering Cancer Center. Head and neck center treatment.

  13. Moffitt Cancer Center. What doctor should I see for a lump on my neck?

  14. Children's Health. Pediatric head and neck lumps.

By Anna Giorgi
Anna Zernone Giorgi is a writer who specializes in health and lifestyle topics. Her experience includes over 25 years of writing on health and wellness-related subjects for consumers and medical professionals, in addition to holding positions in healthcare communications.