What is the initial approach to managing a patient with multinodular nontoxic goiter?

Initial Management of Multinodular Nontoxic Goiter

Ultrasound is the preferred first-line imaging modality for suspected multinodular nontoxic goiter, followed by TSH measurement to confirm euthyroid status, with fine-needle aspiration biopsy of nodules exhibiting suspicious sonographic features. 1

Diagnostic Workup Algorithm

Step 1: Confirm Thyroid Function

• Measure serum TSH to establish that the goiter is truly nontoxic (normal TSH) rather than toxic multinodular goiter (suppressed TSH). 1, 2
• TSH is the most sensitive and reliable index of thyroid function in this setting. 3
• If TSH is suppressed, the patient has thyrotoxicosis and requires different management (radioiodine or surgery). 1

Step 2: Initial Imaging with Ultrasound

• Thyroid ultrasound is the preferred first-line imaging to confirm the neck mass arises from the thyroid and characterize the size and morphology of the goiter. 1
• Ultrasound evaluates the number, size, and sonographic features of nodules to identify those requiring biopsy. 2
• Suspicious ultrasound features include: hypoechogenicity, microcalcifications, absence of peripheral halo, irregular borders, solid aspect, intranodular blood flow, and taller-than-wide shape. 1

Step 3: Fine-Needle Aspiration Biopsy

• Perform FNA on nodules with suspicious ultrasound features to exclude malignancy, as approximately 5% of nodules may harbor cancer. 1, 2
• FNA should be performed on any nodule >1 cm with suspicious features or on smaller nodules if there is clinical suspicion (history of head/neck irradiation, family history of thyroid cancer, cervical adenopathy). 1
• In multinodular goiter, target nodules with suspicious ultrasound characteristics rather than biopsying all nodules. 1

Step 4: Additional Imaging for Specific Indications

• CT neck without contrast is superior to ultrasound for evaluating substernal extension, deep retropharyngeal extension, and degree of tracheal compression when obstructive symptoms are present (dyspnea, orthopnea, dysphagia, dysphonia). 1
• CT is particularly valuable for surgical planning when compression symptoms suggest surgery may be beneficial. 1
• Radionuclide scanning is not helpful in euthyroid patients for determining malignancy risk, as most nodules are "cold" and most cold nodules are benign. 1

Management Based on Findings

If FNA Shows Malignancy

• Refer for surgery immediately. 2

If FNA Shows Indeterminate/Suspicious Cytology

• Surgery is generally advised unless autonomous function can be confirmed by scintigraphy, though most will prove benign. 2

If FNA Shows Benign Cytology

For symptomatic patients with compressive symptoms:

• Surgery is the preferred treatment for large goiters causing dysphagia, choking sensation, or airway obstruction. 3, 2
• Radioiodine is a safe and effective alternative, particularly for patients who are poor surgical candidates. 3, 4, 2

For asymptomatic patients with benign cytology:

• Observation with periodic follow-up is appropriate, including yearly neck palpation and ultrasound examination. 3, 2
• Levothyroxine suppression therapy remains controversial and is often unsuccessful for reducing multinodular goiter size. 3, 4
• Avoid levothyroxine in patients with suppressed TSH to prevent iatrogenic hyperthyroidism. 3

Common Pitfalls to Avoid

• Do not use radionuclide scanning in euthyroid patients to decide on biopsy—it has low positive predictive value. 1
• Do not skip ultrasound evaluation—it is essential for identifying which nodules in a multinodular goiter require FNA. 1, 2
• Do not order FDG-PET/CT as initial imaging for goiter evaluation—it is not recommended. 1
• Do not use levothyroxine suppression routinely—it has potential for adverse effects from exogenous hyperthyroidism and limited efficacy. 3
• Do not assume all nodules are benign—approximately 5% harbor malignancy, necessitating selective FNA of suspicious nodules. 2