What is the best initial imaging modality for a 54-year-old female with a history of childhood lymphoma treated with radiation, now presenting with a hard neck nodule, hoarseness, dysphagia, and a 25-year smoking history?

Best Initial Imaging for Suspected Head and Neck Malignancy

CT neck with IV contrast is the best initial imaging modality for this patient, and should be combined with CT chest (with or without IV contrast) given her 25-year smoking history. 1

Primary Neck Imaging

Contrast-enhanced CT neck is the preferred initial study for evaluating a palpable hard neck mass in an adult, particularly when head and neck cancer is suspected. 1 This patient's constellation of findings—hard neck nodule, hoarseness, dysphagia, significant smoking history, and prior radiation exposure—creates extremely high suspicion for malignancy, likely laryngeal or hypopharyngeal cancer with nodal metastasis.

Why CT Neck with IV Contrast

• Superior spatial resolution makes CT the optimal modality for initial evaluation of neck masses in adults at risk for head and neck cancer 1
• IV contrast is essential for detecting nodal necrosis, identifying the primary tumor within the upper aerodigestive tract, and clarifying the relationship of masses to major neck vessels 1
• Provides anatomic delineation of both the primary site and nodal disease 1
• Evaluates deep neck spaces that ultrasound cannot adequately assess 1

Alternative Considerations

MRI orbits, face, and neck without and with IV contrast is an equally appropriate alternative to CT neck, as both are recommended for initial staging of oral cavity, oropharynx, hypopharynx, or larynx cancer 1. However, CT is typically preferred for initial evaluation given its wider availability, faster acquisition, and superior assessment of osseous structures 1.

Mandatory Chest Imaging

CT chest imaging is strongly indicated in this patient and should be performed at the time of initial staging. 1

Critical Indications Present

• 25-year smoking history is a separate indication for chest CT at initial staging, as tobacco use increases risk for both head and neck squamous cell carcinoma and primary lung cancer 1
• 7-14% of patients have a second lung primary at initial staging of head and neck squamous cell carcinoma 1
• This patient qualifies for lung cancer screening per U.S. Preventative Services Task Force guidelines based on her smoking history 1, 2
• Screening for pulmonary metastases is appropriate given the likely advanced stage disease suggested by her symptoms 1

CT Chest Protocol Options

Either CT chest with IV contrast or without IV contrast is appropriate 1:

• With IV contrast: Improves detection of mediastinal/hilar adenopathy and helps distinguish nodes from vessels 1
• Without IV contrast: Accurately identifies pulmonary metastases and is part of routine clinical practice 1

Role of Additional Imaging

FDG-PET/CT

FDG-PET/CT is NOT appropriate as an initial imaging study for a neck mass 1. However, it becomes a recommended complementary study once the diagnosis is established, performed in combination with diagnostic CT or MRI to provide metabolic information and map systemic involvement 1.

Ultrasound

Ultrasound has limited utility as a primary imaging modality in this clinical scenario 1:

• May be appropriate as an adjunct for nodal evaluation and biopsy guidance 1
• Has limited performance in deep neck spaces and is insufficient for diagnosing deep compartment extension, perineural spread, bone invasion, and retropharyngeal nodal involvement 1

Laryngoscopy Considerations

While not an imaging study, the hoarseness warrants evaluation of the recurrent laryngeal nerve pathway. If vocal fold paralysis is found on laryngoscopy, imaging from skull base to thoracic inlet/aortic arch is indicated to evaluate the entire nerve course 1.

Common Pitfalls to Avoid

• Do not order plain chest radiography instead of CT chest—sensitivity for detecting pulmonary metastases is only 28% compared to CT 1
• Do not skip chest imaging in smokers with head and neck cancer—the dual risk for synchronous lung primary and metastatic disease makes this essential 1
• Do not perform CT without IV contrast for the neck evaluation—contrast is critical for distinguishing vessels from nodes and identifying nodal necrosis 1
• Avoid dual-phase CT (without and with contrast) as it is not usually necessary and increases radiation exposure 1

Radiation Exposure Context

Given this patient's childhood radiation exposure for lymphoma, there is heightened concern about additional radiation. However, the clinical urgency of diagnosing likely malignancy outweighs radiation concerns in this scenario. All imaging should follow ALARA (as low as reasonably achievable) principles with optimized protocols 1.