What is the recommended workup and management for a 40-year-old male with an incidental finding of a multinodular goitre and a normal Thyroid-Stimulating Hormone (TSH) level?

Management of Multinodular Goiter in a 40-Year-Old Male with Normal TSH

For a 40-year-old male with an incidental finding of multinodular goiter and normal TSH, the recommended workup includes thyroid ultrasound to evaluate nodule characteristics, with fine-needle aspiration (FNA) biopsy indicated for nodules exceeding 1 cm in size or those with suspicious ultrasound features. 1

Initial Evaluation

Laboratory Testing

• Confirm normal thyroid function with TSH (already done)
• Consider additional tests:
  • Free T4 to assess thyroid hormone levels
  • Thyroid antibodies (TPO-Ab) to evaluate for autoimmune thyroid disease
  • Calcitonin if medullary thyroid cancer is suspected 1

Imaging

• Thyroid ultrasound: Essential first-line imaging to:

  • Confirm presence of nodules
  • Evaluate number, size, and sonographic features of nodules
  • Identify suspicious features that may indicate malignancy
  • Assist in selecting nodules for FNA biopsy 2, 1

• Radionuclide scan: Not routinely recommended for euthyroid patients with multinodular goiter 2, 1

  • Only indicated if symptoms of hyperthyroidism develop or TSH becomes suppressed

• CT imaging: Consider only if there are concerns about:

  • Substernal extension
  • Tracheal compression
  • Significant compressive symptoms 1

Biopsy Considerations

FNA Biopsy Indications

• Nodules >1 cm in diameter
• Target the largest nodule and any nodules with suspicious ultrasound features
• Nodules <1 cm with risk factors (family history of thyroid cancer, history of radiation exposure) 1, 3

Management Options

Observation

• Appropriate for asymptomatic patients with benign cytology
• Regular monitoring with:
  • Thyroid function tests annually
  • Ultrasound follow-up at 6-12 month intervals initially, then annually if stable 1, 3

Surgical Management

• Consider if:
  • FNA reveals malignancy or suspicious (indeterminate) cytology
  • Large goiter causing compressive symptoms (dysphagia, choking sensation, airway obstruction)
  • Cosmetic concerns 3, 4

Non-Surgical Options

• Levothyroxine suppressive therapy:

  • Not routinely recommended due to limited efficacy and potential adverse effects (bone density loss, atrial fibrillation) 1, 4

• Radioactive iodine therapy:

  • May be considered for patients who decline surgery or have contraindications due to comorbidities
  • More commonly used in Europe than in the United States
  • Can be effective for volume reduction in nontoxic multinodular goiter 5, 6

Follow-up Recommendations

• For patients with benign, asymptomatic multinodular goiter:

  • Annual TSH measurement
  • Periodic ultrasound evaluation (every 6-12 months initially, then annually if stable)
  • Repeat FNA if significant growth or development of suspicious sonographic features 1, 3

• Monitor for development of:

  • Hyperthyroidism (toxic multinodular goiter)
  • Compressive symptoms
  • Changes in nodule characteristics 7

Common Pitfalls to Avoid

1. Overlooking suspicious nodules: Don't focus only on the largest nodule; evaluate all nodules for suspicious features.

2. Unnecessary levothyroxine therapy: Avoid prescribing levothyroxine for suppression in euthyroid patients, as evidence for efficacy is limited and risks include cardiac effects and bone density loss.

3. Inadequate follow-up: Multinodular goiter requires ongoing surveillance even when initially benign, as changes can occur over time.

4. Missing substernal extension: Consider CT imaging if there's clinical suspicion of substernal extension, as this may not be fully visualized on ultrasound.