What is the initial management for a patient presenting with thyroid goiter?

Initial Management of Thyroid Goiter

Begin with thyroid function tests (TSH) followed immediately by thyroid ultrasound—these two tests form the essential foundation for all subsequent management decisions. 1, 2

Diagnostic Algorithm

Step 1: Thyroid Function Testing

• Measure TSH first as it is the most sensitive initial test (98% sensitivity, 92% specificity) and will guide your entire imaging pathway 2
• Add free T4 and free T3 to evaluate the functional status of the thyroid 2
• The TSH result determines whether additional nuclear imaging is needed or contraindicated 1

Step 2: Thyroid Ultrasound (Perform in ALL Cases)

• Ultrasound is the mandatory first-line imaging modality regardless of TSH level 1, 2
• It confirms the mass originates from thyroid tissue 2
• It characterizes goiter size, morphology, and identifies nodules 2
• It stratifies malignancy risk using ACR TI-RADS criteria for any nodules present 2
• Critical pitfall to avoid: Never skip ultrasound and proceed directly to nuclear imaging, as you will miss coexisting thyroid nodules requiring biopsy for malignancy evaluation 1

Step 3: TSH-Guided Additional Testing

If TSH is LOW (thyrotoxicosis):

• Proceed to radioiodine uptake scan after ultrasound 1
• This differentiates Graves' disease, toxic adenoma, toxic multinodular goiter, and thyroiditis 1
• The scan also helps plan radioactive iodine therapy if needed 1

If TSH is NORMAL (euthyroid):

• Do NOT order radionuclide scanning—it wastes resources and has low diagnostic value in euthyroid patients 1, 2
• Radionuclide scanning has low positive predictive value for malignancy and does not help decide which nodules to biopsy 1, 2
• Use ultrasound findings alone to guide fine-needle aspiration biopsy decisions based on ACR TI-RADS criteria 2

If TSH is HIGH (hypothyroidism):

• Imaging is generally not indicated 1
• If imaging is needed for other reasons, ultrasound is appropriate but does not differentiate causes of hypothyroidism 1

Step 4: Evaluate for Compressive Symptoms

If patient has dyspnea, orthopnea, dysphagia, or dysphonia:

• Add CT scan of neck and chest to evaluate substernal extension and tracheal compression 3, 2, 4
• CT is superior to ultrasound for evaluating substernal extension and defining the degree of tracheal compression 3, 2
• CT has less respiratory motion artifact than MRI 3
• Surgical referral is indicated for goiters causing compressive symptoms 4

Specific compressive findings requiring CT:

• Retrosternal extension into the mediastinum can cause significant tracheal compression 3
• Symptoms include progressive dyspnea (especially when lying flat), obstructive sleep apnea, and stridor 3
• Choking and dyspnea are the most common presenting symptoms of retrosternal goiter 5

Management Based on Findings

For Nodular Goiter:

• Use ACR TI-RADS criteria from ultrasound to select nodules for fine-needle aspiration biopsy 2
• Biopsy should only occur after ultrasound characterization, not as an initial diagnostic study 2
• The malignancy rate in retrosternal goiters is approximately 12% 5

For Symptomatic/Compressive Goiter:

• Surgical thyroidectomy is the treatment of choice for goiters with compressive symptoms 4, 5
• Most patients (91%) can be approached through a cervical incision 5
• Median sternotomy is required in approximately 9% of cases 5
• Studies demonstrate improved breathing and swallowing outcomes after thyroidectomy 4

For Toxic Goiter (Low TSH):

• Treatment options include radioactive iodine therapy, which has 98% success rate for hot nodules 1
• Radioiodine therapy causes mean 32% nodule volume reduction at 6 months 1
• Surgery is also an option for toxic multinodular goiter 6

Common Pitfalls to Avoid

• Never proceed directly to uptake scan without checking TSH and performing ultrasound first 1
• Never use radionuclide scanning to determine malignancy in euthyroid patients 1, 2
• Never skip ultrasound evaluation—structural abnormalities like substernal extension or suspicious nodules will be missed 1
• Never order PET/CT with FDG for initial goiter evaluation—it has no role 2