What is the assessment and plan for a non-toxic multinodular goiter?

Assessment and Management of Non-Toxic Multinodular Goiter

The initial assessment of non-toxic multinodular goiter should include thyroid function tests, ultrasound imaging, and targeted fine-needle aspiration biopsy (FNAB) of suspicious nodules, followed by treatment based on symptoms, goiter size, and malignancy risk. 1, 2

Initial Diagnostic Evaluation

• Thyroid function tests should be performed first to confirm euthyroid status (normal TSH) and rule out thyrotoxicosis 1
• Ultrasound is the preferred first-line imaging modality to:
  • Confirm that the neck mass is arising from the thyroid 1, 3
  • Characterize the size and morphology of the goiter 1
  • Evaluate individual nodules for suspicious features using ACR TI-RADS criteria 1, 2
• CT scan should be added when:
  • Substernal extension is suspected 1, 3
  • Evaluation of tracheal compression is needed 1, 4
  • There are concerns about invasive features 2, 3
• Fine-needle aspiration biopsy (FNAB) should be performed on:
  • Nodules meeting size criteria based on ACR TI-RADS risk stratification 1, 2
  • Prominent palpable nodules 5, 6
  • Nodules with suspicious sonographic features 1, 2

Management Options Based on Clinical Presentation

For Asymptomatic Non-Toxic Multinodular Goiter

• Observation with yearly clinical follow-up is appropriate for:
  • Small, asymptomatic goiters 5, 6
  • Patients with benign FNAB results 5, 6
  • Follow-up should include thyroid palpation and TSH measurement 5, 6

For Symptomatic Non-Toxic Multinodular Goiter

• Surgical treatment is the preferred option for:

  • Large goiters causing compressive symptoms (dyspnea, orthopnea, obstructive sleep apnea, dysphagia, dysphonia) 1, 4, 5
  • Nodules with malignant or suspicious cytology 5, 6
  • Cosmetic concerns with large visible goiters 5

• Radioactive iodine (RAI) therapy is an alternative treatment option for:

  • Elderly patients with comorbidities that increase surgical risk 7, 8
  • Recurrent goiter after previous surgery 7, 8
  • RAI can achieve mean thyroid volume reduction of 40% after 1 year and 50-60% after 3-5 years 7

For Toxic Multinodular Goiter (if TSH is suppressed)

• Treatment options include:
  • Surgery (preferred for large goiters) 5
  • Radioactive iodine 5, 9

Follow-Up Recommendations

• For patients managed with observation:

  • Annual thyroid function tests 5, 6
  • Periodic ultrasound examination 6
  • Re-evaluation of symptoms 2

• After thermal ablation (if chosen as treatment):

  • Follow-up at 1,3,6, and 12 months in the first year 1
  • Annual follow-up for benign nodules after the first year 1
  • Assessment of volume reduction rate (VRR) and symptom improvement 1

Common Pitfalls to Avoid

• Do not rely solely on CT or MRI to differentiate between benign and malignant nodules, as these modalities have limited utility for this purpose 1, 3
• Avoid using levothyroxine suppression therapy in patients with suppressed TSH levels to prevent exacerbating thyrotoxic symptoms 5
• Do not overlook the need for CT imaging when evaluating substernal extension, as ultrasound has limitations in assessing the inferior border of disease 2, 3
• Be aware that radioiodine therapy for non-toxic goiter carries a 5% risk of developing autoimmune hyperthyroidism and 20-30% risk of hypothyroidism at 5 years 7