For a patient whose non‑contrast chest CT shows an incompletely assessed hilar mass, mediastinal lymphadenopathy, possible breast or chest‑wall lesions, and an indeterminate thoracic esophagus, what is the appropriate next imaging and management step?

Next Step: Contrast-Enhanced CT Chest

The appropriate next step is a contrast-enhanced CT chest to adequately assess the incompletely evaluated hilar mass, mediastinal lymphadenopathy, and chest wall structures that cannot be characterized on non-contrast imaging. 1

Rationale for Contrast-Enhanced CT

The ACR Appropriateness Criteria explicitly state that cancer staging, incidental mass workup, and nodules with associated lymphadenopathy fall outside the scope of non-contrast CT protocols and require contrast enhancement for proper evaluation. 1 While non-contrast CT is appropriate for isolated pulmonary nodule surveillance, this clinical scenario involves multiple incompletely assessed structures that require tissue characterization:

Critical Structures Requiring Contrast Enhancement

• Hilar mass and lymphadenopathy: Cannot be adequately assessed without intravenous contrast to differentiate vascular structures from pathologic masses and to characterize lymph node enhancement patterns 1

• Mediastinal lymphadenopathy: Requires contrast to distinguish enlarged lymph nodes from vascular structures and to assess for pathologic enhancement 1

• Breast and chest wall masses: Cannot be adequately characterized on non-contrast CT; contrast enhancement is essential for evaluating soft tissue lesions 1

• Thoracic esophagus: A decompressed esophagus requires contrast (both IV and potentially oral) for adequate wall assessment and detection of masses or thickening 1

Specific Technical Recommendations

Order a CT chest with IV contrast using thin-section technique (1.5 mm slices) with multiplanar reconstructions. 2, 3, 4 This protocol will:

• Characterize the hilar mass and assess for vascular invasion or encasement
• Evaluate mediastinal and hilar lymph node size, morphology, and enhancement patterns
• Better delineate chest wall and breast lesions
• Assess the esophageal wall when distended with oral contrast if clinically indicated

Additional Imaging Considerations

Axillary Assessment

If breast or chest wall masses are identified, dedicated ultrasound of the axilla is the most appropriate next step for evaluating suspicious axillary lymph nodes, as it allows for real-time assessment and potential US-guided biopsy if indicated. 1

Upper Abdominal Findings

The partially imaged upper abdomen should be included in the contrast-enhanced chest CT field of view to complete the evaluation of any incidental findings. 5

Management Algorithm

1. Immediate step: Order CT chest with IV contrast (thin-section protocol)
2. If hilar mass confirmed: Proceed to tissue diagnosis via bronchoscopy or CT-guided biopsy depending on location and accessibility
3. If mediastinal lymphadenopathy confirmed: Consider PET/CT for staging if malignancy is suspected based on contrast-enhanced CT findings 1
4. If breast/chest wall lesions identified: Add dedicated breast imaging (mammography/ultrasound) and axillary ultrasound 1
5. If esophageal abnormality identified: Consider upper endoscopy for direct visualization and biopsy

Critical Pitfalls to Avoid

• Do not order repeat non-contrast CT: This will not resolve the diagnostic limitations already encountered 1
• Do not proceed directly to PET/CT: PET/CT is premature without first obtaining adequate anatomic characterization with contrast-enhanced CT 1
• Do not delay contrast study for isolated nodule protocols: The presence of a mass (not just a nodule) and lymphadenopathy requires immediate contrast evaluation, not surveillance imaging 1
• Verify renal function before contrast administration: Ensure adequate kidney function to minimize contrast-induced nephropathy risk 5