Evaluation and Management of Unilateral Neck Masses in Adults

Introduction to Unilateral Neck Masses

Approximately half of all persistent neck masses in adults are malignant, with head and neck squamous cell carcinoma (HNSCC) and lymphoma being the most critical diagnoses to consider, particularly in patients over 40 years with tobacco/alcohol use or those with HPV-related oropharyngeal cancer 1, 2, 3
The American Academy of Otolaryngology-Head and Neck Surgery identifies specific characteristics that mandate urgent evaluation for malignancy, including mass present ≥2 weeks, size >1.5 cm, firm consistency, fixed to adjacent tissues, ulceration of overlying skin, and non-tender mass 1, 4, 5, 8, 9, 10

Head and Neck Squamous Cell Carcinoma (HNSCC) is the leading cause of malignant neck masses, presenting as metastatic cervical lymphadenopathy from primary sites including oropharynx, oral cavity, larynx, hypopharynx, and nasopharynx 1, 2, 3
HPV-positive oropharyngeal cancer is rapidly increasing in incidence, now representing over 70% of new oropharyngeal cancers, often presenting in younger patients with minimal tobacco exposure and a unilateral neck mass as the sole presenting symptom 2, 3
Cutaneous malignancies, such as melanoma and squamous cell carcinoma of the face, scalp, or neck, can metastasize to cervical nodes 1, 4, 5
Metastases from distant sites are less common but possible 2, 3

Historical features that suggest high risk include age >40 years, tobacco and alcohol use, absence of infectious etiology, prior head and neck malignancy, and unexplained weight loss 1, 4, 5, 9, 10
Associated symptoms suggesting primary malignancy include ipsilateral otalgia, unilateral hearing loss, dysphagia, voice change, tonsil asymmetry, oral cavity/oropharyngeal ulceration, nasal obstruction and epistaxis, and skin lesions on face, neck, or scalp 1, 4, 5, 9

High-risk patients require immediate workup, including imaging, fine-needle aspiration, and referral to otolaryngology for examination of the upper aerodigestive tract 1, 4, 6, 7
Low-risk patients with suspected infection may be treated with a single course of broad-spectrum antibiotics, but mandatory reassessment within 2 weeks is required to monitor for resolution or progression 6, 7

The most dangerous error is assuming a neck mass in an adult is infectious and prescribing multiple courses of antibiotics without definitive diagnosis, which delays cancer diagnosis and worsens outcomes 6, 7
HPV-positive oropharyngeal cancer patients are frequently misdiagnosed as "low-risk" due to their younger age and lack of traditional risk factors, leading to diagnostic delays 2, 3