Management of Heterogeneous Enlarged Thyroid Gland

Initial Clinical Assessment

• The American College of Radiology recommends evaluating patients with a heterogeneous enlarged thyroid gland for compression symptoms, such as dyspnea, orthopnea, obstructive sleep apnea, dysphagia, and dysphonia, to determine the need for cross-sectional imaging or surgical intervention 1, 3

Ultrasound Characterization of Individual Nodules

• The American College of Radiology recommends applying ACR TI-RADS scoring to any identifiable nodular areas based on composition, echogenicity, shape, margins, and echogenic foci to determine the risk of malignancy 2, 4
• Fine-needle aspiration biopsy thresholds based on TI-RADS classification are: TI-RADS 3 (mildly suspicious): FNA if ≥1.5 cm, TI-RADS 4 (moderately suspicious): FNA if ≥1.0 cm, TI-RADS 5 (highly suspicious): FNA if ≥1.0 cm 2, 4

Additional Imaging for Substernal Extension

• The American College of Radiology recommends ordering CT neck with contrast if the patient has obstructive symptoms, physical examination suggests substernal extension, or ultrasound cannot visualize the inferior border of the thyroid 1, 2, 3
• CT is superior to ultrasound for evaluating substernal extension and quantifying tracheal compression, which is critical for surgical planning, and the ACR specifically recommends CT over MRI due to less respiratory motion artifact 1, 2

Management Based on Findings

• The National Comprehensive Cancer Network recommends referring patients with malignant or suspicious cytology for surgical evaluation with total thyroidectomy and appropriate lymph node dissection based on extent of disease 5
• Surgical referral is indicated when significant obstructive symptoms are present, CT demonstrates substantial tracheal compression, or progressive growth causes increasing symptoms 1, 3

Important Pitfalls to Avoid

• The American College of Radiology recommends not using levothyroxine suppression therapy, as it is controversial, often unsuccessful for multinodular goiters, and carries risk of iatrogenic hyperthyroidism 1
• The American College of Radiology recommends not ordering radioiodine uptake scan in euthyroid patients, as scintigraphy is not helpful for determining malignancy risk when TSH is normal 1
• Assessing vocal cord mobility before any surgical intervention using ultrasound, mirror laryngoscopy, or fiberoptic laryngoscopy to document baseline function is recommended 3