A soft tissue mass in the neck is a term for an unexplained lump or swelling. It is not a specific diagnosis but a clinical finding that requires further investigation. The neck is a complex anatomical region containing many structures, including muscles, the thyroid gland, salivary glands, and an extensive network of lymph nodes, any of which can be the origin of a mass. Discovering such a lump can be concerning, but many are caused by benign, or non-cancerous, conditions.
This information is for educational purposes and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or another qualified health provider with any questions about a medical condition.
Potential Benign Causes
The most common cause of a neck lump is swollen lymph nodes, a condition called lymphadenopathy. Lymph nodes are small glands in the immune system that can swell in response to infections like the common cold, strep throat, or a dental infection. This swelling, known as reactive lymphadenopathy, is the body’s normal reaction to fighting pathogens.
Lipomas are another frequent cause of benign neck masses. These are soft, slow-growing tumors of fat cells that form just under the skin. A lipoma feels soft, rubbery, and can be moved easily with gentle pressure. While they can appear anywhere, about 25% of lipomas occur in the head and neck region, most often in the posterior part of the neck, and are painless unless they grow large enough to compress a nearby nerve.
Cysts are closed sacs filled with fluid, semi-solid material, or air. Sebaceous cysts, for instance, form from skin glands and are filled with a thick, oily substance. More specific to the neck are developmental cysts, such as branchial cleft cysts and thyroglossal duct cysts, which are remnants of embryonic tissue. A branchial cleft cyst usually appears on the side of the neck, while a thyroglossal duct cyst is typically located in the midline and may move up and down with swallowing.
The thyroid gland, at the front of the neck, can also be a source of lumps. A generalized enlargement of the gland is a goiter, while individual lumps are thyroid nodules. The vast majority of thyroid nodules are benign. They can be solid or fluid-filled and often cause no symptoms, though a large nodule could cause difficulty with swallowing or breathing.
Potential Malignant Causes
While most neck lumps are benign, the possibility of a malignant origin must be considered. A mass can represent a primary cancer starting in the neck or cancer that has spread from another part of the body. A persistent neck mass in an adult requires evaluation to rule out malignancy.
Lymphoma is a cancer that originates in the cells of the lymphatic system. It can present as one or more enlarged, rubbery, and often painless lymph nodes in the neck. Unlike nodes swollen from infection, those affected by lymphoma may grow progressively and be accompanied by other symptoms like fever, night sweats, and unexplained weight loss.
Cancers can also arise from other tissues within the neck. Thyroid cancer presents as a nodule on the thyroid gland, and while most nodules are benign, a small percentage are cancerous. Sarcomas are a rarer group of cancers that develop from the soft tissues, such as muscles, fat, or connective tissues. A soft tissue sarcoma in the neck might be felt as a firm, often painless lump that gradually increases in size.
A new neck mass in an adult raises the concern of metastatic cancer. This occurs when cancer cells from a primary tumor elsewhere travel through the lymphatic system to the neck’s lymph nodes. Common primary sites include the mouth, throat, voice box, and salivary glands. Less commonly, cancers from below the clavicle, like lung or breast cancer, can spread to neck lymph nodes.
The Diagnostic Process
A healthcare provider will begin with a medical history and a physical examination. The history includes questions about the lump’s duration, changes in size, associated symptoms, and risk factors like tobacco and alcohol use. During the physical exam, the doctor will feel the mass to assess its size, location, consistency (whether it is soft, firm, or hard), and mobility (whether it is fixed to surrounding tissues).
Following the initial assessment, imaging studies are the next step to visualize the mass. An ultrasound is often the first imaging test used. It is non-invasive, does not use radiation, and uses sound waves to determine if a mass is solid or fluid-filled (cystic), a distinction that helps narrow down potential causes.
For more detailed information, a computed tomography (CT) scan or magnetic resonance imaging (MRI) may be ordered. A CT scan provides cross-sectional images of the neck’s soft tissues, bones, and blood vessels, helping to define the mass’s precise location and extent. An MRI uses powerful magnets and radio waves to generate highly detailed images of soft tissues, which is useful for evaluating a mass’s relationship to nerves and muscles.
The definitive way to determine if a mass is benign or malignant is through a biopsy, which involves taking a sample of tissue or cells for examination by a pathologist. The most common and least invasive method is a fine-needle aspiration (FNA), where a thin needle is inserted into the mass to withdraw a small sample of cells. If more tissue is needed, a core needle biopsy uses a larger needle to obtain a small cylinder of tissue, or an excisional biopsy may be performed to surgically remove the entire lump for both diagnosis and treatment.
Common Treatment Approaches
Treatment for a soft tissue mass in the neck is entirely dependent on the final diagnosis. For benign masses, treatment may not be necessary. A strategy of “watchful waiting” is employed for conditions like small lipomas or benign thyroid nodules, which involves monitoring the mass over time. If a benign cyst becomes inflamed or causes discomfort, it can be drained or surgically removed, while a swollen lymph node from a bacterial infection is treated with antibiotics.
When a neck mass is malignant, treatment is managed by a multidisciplinary team of specialists. The primary treatment for most localized cancers in the neck, including thyroid cancer, sarcomas, and early-stage metastatic disease, is surgical removal of the tumor and affected lymph nodes. Surgery is often followed by other therapies to eliminate any remaining cancer cells.
Radiation therapy uses high-energy beams to destroy cancer cells and may be used after surgery or as the main treatment if surgery is not an option. Chemotherapy uses drugs to kill cancer cells and is used for cancers that have spread or for lymphomas. In recent years, targeted therapies and immunotherapies, which are designed to attack specific characteristics of cancer cells or boost the body’s immune response, have become important options for treating various types of head and neck cancers.