A neck mass is any noticeable swelling, lump, or localized enlargement in the neck region. These masses can originate from various tissues, including the skin, lymph nodes, salivary glands, or the thyroid. While many neck masses are benign, some can be malignant. Understanding their nature is important for appropriate medical evaluation.
The Likelihood of Cancer in a Neck Mass
The percentage of neck masses that are cancerous varies significantly, largely depending on the patient’s age and other contributing factors. For adults over 40, the concern for malignancy increases, with some sources indicating that up to 80% of non-thyroid neck masses in this age group are neoplastic, and 80% of those are malignant. In a study of adults referred to otolaryngology for a neck mass, malignancy was found in 5% of patients overall, with rates increasing from 2.1% for those under 40 to 8.4% for those 70 or older.
In children, neck masses are commonly inflammatory or congenital, with about a 90% probability of being benign. However, for adults, especially those over 40, a persistent neck mass warrants medical evaluation due to malignancy concerns. Other factors influencing cancer risk include sex, with males having more than twice the odds of malignancy compared to females. White non-Hispanic patients also show a higher risk.
Lifestyle choices and exposures also play a role in the risk of malignancy. Tobacco use and alcohol consumption are major risk factors for many head and neck cancers. Exposure to the human papillomavirus (HPV), particularly HPV 16, is increasingly linked to oropharyngeal cancers, which can present as asymptomatic neck masses. A mass larger than 1.5 cm or one with ill-defined borders on imaging is also associated with a higher risk of malignancy.
Distinguishing Benign from Cancerous Masses
Neck masses can arise from congenital, inflammatory/infectious, or neoplastic sources. Benign masses are non-cancerous and do not spread. Common benign neck masses include enlarged lymph nodes due to infections like colds, strep throat, or mononucleosis. These lymph nodes swell during infection and shrink as it resolves.
Congenital cysts, present from birth, are another type of benign mass. Examples include thyroglossal duct cysts, which form in the midline and may appear during upper respiratory infections, and branchial cleft cysts, which develop along the sides of the neck. Other benign tumors include lipomas, which are soft, fatty lumps, and fibromas. Thyroid nodules, while common, are also largely benign, with only about 5% being malignant.
In contrast, cancerous neck masses often represent either primary cancers originating in the head and neck region or metastatic cancers that have spread from a distant site. Primary head and neck cancers frequently originate in the mouth, throat, voice box (larynx), or salivary glands. Squamous cell carcinoma accounts for a large proportion of head and neck malignancies. Other primary cancers include thyroid cancer, lymphoma, and salivary gland cancer. Metastatic neck masses are often enlarged lymph nodes where cancer cells from a primary tumor elsewhere in the body, such as the lung, breast, or kidney, have spread.
When to Seek Medical Attention and What to Expect
Any new or changing neck mass, especially if it persists for more than two to three weeks, warrants medical evaluation. Certain characteristics can raise suspicion for malignancy, including rapid growth, a hard or firm consistency, and immobility. Associated symptoms like persistent hoarseness or voice changes, difficulty swallowing or breathing, unexplained weight loss, or persistent ear pain on the same side should also prompt immediate attention. A sore in the mouth that does not heal or recurrent nosebleeds can also be warning signs.
Upon presentation, a doctor will begin with a thorough medical history and a physical examination of the head and neck, including palpation of the mass and surrounding areas. They may also perform an endoscopy to visualize the inside of the throat and voice box. Imaging tests are commonly used to further characterize the mass. An ultrasound can help differentiate between solid and fluid-filled masses and guide biopsies. Computed tomography (CT) scans and magnetic resonance imaging (MRI) provide detailed pictures of the mass’s size, location, and relationship to surrounding structures.
A definitive diagnosis typically requires a biopsy, which involves taking a tissue sample for microscopic examination. A fine-needle aspiration biopsy (FNAB) is often the initial test, where a small needle extracts cells from the mass. If an FNAB is inconclusive, a core biopsy or an open biopsy may be performed.