Thyroid Nodule

Red Flags (Malignancy)

  • History
    • Rapid growth
    • Dysphonia
    • Dysphagia
    • Dyspnea
    • Hx of radiotherapy (head and neck, total body)
    • Familial thyroid carcinoma
    • Thyroid cancer syndromes (MEN2, FAP, Cowden)
  • Physical Exam
    • Larger than 4 cm
    • Firmness to palpation
    • Fixation of the nodule to surrounding tissue
    • Regional lymphadenopathy
    • Vocal fold immobility (on flexible laryngoscopy)


  • Thyroid ultrasound
  • TSH if nodules >1cm
    • If low (< 0.3 mU/L), radionuclide thyroid scan I-123
      • Toxic multinodular goiter vs. hyperfunctioning nodule (consider ablation)
    • If TSH normal or high, consider FNA if meets criteria as below

Threshold for FNA

  • ≥ 1.0 cm solid hypoechoic nodule
    • Higher risk of irregular margins, microcalcifications, taller-than-wide, rim calcification, extrathyroidal extension
  • ≥ 1.5 cm isoechoic or hyperechoic solid nodule, or partially cystic nodule with eccentric solid area without any ultrasonographic features
  • ≥ 2.0 cm spongiform or partially cystic without any ultrasonographic features

No biopsy required for purely cystic nodules as <1% malignancy