Radioiodine uptake in the head and neck

Area of Science:

• Nuclear Medicine
• Oncology
• Radiology

Background:

• Radioiodine whole-body scanning is crucial for detecting metastatic thyroid cancer.
• False-positive findings in the head and neck region can lead to misdiagnosis.

Observation:

• Two cases presented with radioiodine uptake in the sinuses, mimicking metastatic disease in patients with a history of thyroid cancer.
• Computed tomography (CT) confirmed sinusitis as the cause of uptake in these cases.

Findings:

• Sinusitis is a significant cause of false-positive radioiodine uptake in the head and neck.
• Eighteen causes of false-positive radioiodine uptake have been reported, categorized into physiologic, nonthyroidal pathologic, internal retention, and external contamination.

Implications:

• Clinicians must differentiate true metastatic disease from benign causes of radioiodine uptake.
• Inflamed paranasal sinuses should be considered in the differential diagnosis of head and neck radioiodine uptake.