Workup of a Soft Tissue Neck Mass in Adults

High‑Risk Clinical Features

A neck mass ≥ 1.5 cm in longest diameter mandates urgent contrast‑enhanced CT and prompt otolaryngology referral. 1
Firm or hard consistency suggests malignancy rather than reactive edema. 1
Fixation to adjacent structures indicates possible capsular invasion. 1
Overlying skin ulceration implies capsular breach or cutaneous extension. 1
Duration ≥ 2 weeks without fluctuation is a high‑risk criterion. 1

Age > 40 years markedly increases the probability of head‑and‑neck squamous cell carcinoma. 1
HPV‑related oropharyngeal carcinoma warrants vigilance even in younger patients without traditional risk factors. 2

Contrast‑enhanced CT of the neck is the first‑line imaging modality for high‑risk masses because it provides superior spatial resolution, detects nodal necrosis, delineates vascular relationships, and assists in locating an occult primary tumor. 1
CT advantages include greater accessibility, higher spatial resolution for oncologic evaluation, and ability to detect intramuscular abscesses. 2
MRI with contrast is an acceptable alternative when CT is contraindicated (e.g., contrast allergy, severe renal impairment). 1
Intravenous contrast is mandatory; non‑contrast studies miss necrotic nodes and fail to guide primary tumor search. 2
Ultrasound alone is insufficient for high‑risk masses, although it may expedite fine‑needle aspiration. 2

FNA is the initial tissue diagnostic procedure and must be performed before any open biopsy. 1
Ultrasound‑guided FNA increases specimen adequacy over palpation‑guided FNA, especially for cystic or necrotic masses. 1
On‑site cytopathology evaluation reduces inadequacy rates when available. 1

Core needle biopsy should be considered after an inadequate or indeterminate FNA. 1
For suspected lymphoma, core needle biopsy is the first‑line approach, with sensitivity ≈ 92 % versus 74 % for FNA. 1
Ultrasound‑guided core biopsy achieves ≈ 95 % adequacy, 94‑96 % accuracy, and about 1 % complication rate. 1

Open biopsy must never be performed before completing FNA, imaging, and endoscopic evaluation, as premature open biopsy can compromise oncologic management if the mass represents a metastatic node. 1

Otolaryngology specialists perform direct endoscopic visualization of the larynx, base of tongue, and pharyngeal mucosa to search for an occult primary lesion. 1

Empiric antibiotics should be withheld unless clear signs of bacterial infection are present (localized warmth, erythema, marked tenderness, fever > 38.5 °C). 1
Most adult neck masses are neoplastic rather than infectious; unnecessary antibiotics delay cancer diagnosis, worsen outcomes, and promote antimicrobial resistance. 1

Biopsy results should be communicated to the patient within one week; if not received, the patient should contact the provider. 1