Guideline Recommendations for Management of Multinodular Goitre

Diagnostic Evaluation

• Serum TSH should be measured as the first‑line test in every patient with multinodular goitre to define thyroid functional status and guide subsequent management. 1
• If TSH is low or suppressed, free T4/T3 should be measured and thyroid scintigraphy performed to identify autonomously functioning (“hot”) nodules, which are common in iodine‑deficient regions. 1, 2
• If TSH is elevated, thyroid peroxidase antibodies and free T4 should be assessed to evaluate for autoimmune thyroiditis. 1
• If TSH is normal, patients should undergo high‑resolution ultrasound‑guided risk stratification and selective fine‑needle aspiration (FNA). 1, 3
• High‑resolution thyroid ultrasound is recommended for all patients with palpable multinodular goitre to characterize nodule size, composition, and sonographic risk features. 1

Fine‑Needle Aspiration Strategy

• Nodules < 5 mm should not be biopsied regardless of appearance; they are monitored with ultrasound surveillance only. 1
• Nodules 5–10 mm merit FNA only when high‑risk ultrasound features (marked hypoechogenicity, microcalcifications, irregular margins, taller‑than‑wide shape) are present and there is a suspicious lymph node, extrathyroidal extension, or personal/family history of thyroid cancer. 1
• Nodules > 10 mm with intermediate risk features (slightly hypoechoic, smooth or ill‑defined margins) should be aspirated when a definitively benign appearance cannot be confirmed. 1
• Nodules ≥ 20 mm that are spongiform, isoechoic, or predominantly cystic (> 50 % fluid) require FNA only if they are progressively enlarging or lack any suspicious features. 1
• Functioning (“hot”) nodules identified on scintigraphy should not be biopsied if they lack suspicious ultrasound characteristics, because malignancy is exceedingly rare in autonomously functioning nodules. 1

Management of Benign Cytology (Bethesda II)

• Patients with benign cytology generally require no active treatment; clinical and ultrasound follow‑up is the standard approach. 1, 3, 4
• The first follow‑up ultrasound is performed at 12 months, a second at 24 months if unchanged, and thereafter every 2–3 years up to 5–7 years. 3, 5
• Repeat FNA is indicated when new suspicious clinical or ultrasound findings appear or when nodule volume increases by > 50 %, a threshold exceeding inter‑observer variability. 1, 3, 4
• In nodules that remain asymptomatic, repeatedly benign, and without suspicious features, routine follow‑up may be discontinued. 3

Medical Therapy

• Levothyroxine suppressive therapy is not recommended for euthyroid patients with benign multinodular goitre because it lacks efficacy and carries risks of iatrogenic hyperthyroidism, atrial fibrillation, and bone loss. 1, 3, 4
• An exception is for young patients living in iodine‑deficient regions who have small nodular goitre and high‑normal TSH; in these cases, modest levothyroxine dosing and iodine supplementation may be considered. 1, 3, 4
• Young patients with subclinical hypothyroidism due to autoimmune thyroiditis should receive levothyroxine replacement (not suppression). 3
• Levothyroxine is not recommended to prevent recurrence after lobectomy when postoperative TSH remains within the normal range. 3

Indications for Definitive Treatment

Surgery

• Surgery is indicated for compressive symptoms clearly attributable to the goitre (e.g., dysphagia, dyspnea, neck tightness, airway obstruction). 1, 3, 4, 6
• Large goitre (> 80 g), substernal or retrosternal extension, or the need for rapid correction of a thyrotoxic state also warrant surgical intervention. 2, 7, 8
• Emergence of suspicious ultrasound features despite prior benign FNA findings is an indication for surgery. 3, 4
• Coexisting or suspected thyroid cancer, or concurrent hyperparathyroidism requiring surgery, are additional surgical indications. 2, 7, 8
• Cosmetic concerns or patient preference after shared decision‑making may justify surgery. 6
• Total thyroidectomy for compressive symptoms achieves symptom resolution in essentially all patients, whereas only ≈ 46 % of patients treated with radioiodine experience improvement in compressive symptoms. 2, 7, 8
• When performed by high‑volume thyroid surgeons, permanent hypoparathyroidism occurs in < 2 % and recurrent laryngeal nerve injury in < 2 %. 2, 7, 8

Radioiodine Therapy

• Radioiodine is appropriate for hyperfunctioning or symptomatic goitre, particularly in older patients, those with significant comorbidities, or those with prior neck surgery/scarring. 2, 7, 8
• Small goitres with adequate radioactive iodine uptake (RAIU) are suitable candidates for radioiodine. 2, 7, 8
• Patients who decline surgery or lack access to a high‑volume thyroid surgeon may be offered radioiodine. 2, 7, 8
• Prior to radioiodine, any coexistent cold (non‑functioning) nodules should undergo FNA to exclude malignancy. 3
• Limitations: In large goitres treated with high‑activity radioiodine, volume reduction is only 30–50 %, and compressive symptom improvement occurs in < 50 % of patients. 2, 7, 8
• Progressive hypothyroidism after radioiodine occurs in 3 % at 1 year, 28 % at 5 years, 46 % at 10 years, and 64 % at 24 years. 2, 7
• Hypothyroidism develops more rapidly in patients with incomplete TSH suppression or the presence of antithyroid antibodies. 2, 7
• Absolute contraindications to radioiodine include pregnancy, lactation, coexisting thyroid cancer, inability to comply with radiation‑safety guidelines, and women planning pregnancy within 4–6 months. 2, 7, 8

Minimally Invasive Procedures

• Percutaneous ethanol injection (PEI) is the first‑line treatment for relapsing benign cystic thyroid lesions and is safe/effective for cysts and complex nodules with a large fluid component. 1, 3, 4
• The solid component of complex lesions should be carefully sampled before PEI. 3
• PEI is not recommended for purely solid nodules (whether hyperfunctioning or not) or for multinodular goitre. 3
• Ultrasound‑guided thermal ablation (laser or radiofrequency) may be considered for solid or complex nodules that are symptomatic, progressively enlarging, or cause cosmetic concern. 1, 3, 4
• Repeat FNA for cytologic confirmation is required before thermal ablation treatment. 3

Common Pitfalls and Caveats

• Not all nodules in a multinodular goitre require biopsy; size and ultrasound risk stratification should be used to select only the most suspicious nodules. 1
• A large goitre does not automatically mandate surgery; asymptomatic euthyroid patients with benign cytology can be safely observed. 1, 3
• Radioiodine is less effective than surgery for relieving compressive symptoms, and the degree of goitre size reduction is modest; surgery remains superior when compression is the primary indication. 2, 7, 8
• Levothyroxine suppression lacks evidence of benefit in euthyroid multinodular goitre and may cause adverse effects such as atrial fibrillation and bone loss. 1, 3
• Fine‑needle aspiration should always be performed under ultrasound guidance; palpation‑guided FNA has high nondiagnostic rates and lower accuracy. 1

American College of Endocrinology & American Association of Clinical Endocrinologists – Guideline Summary for Evaluation and Management of Goiter

Initial Evaluation

• Measure serum TSH as the first‑line laboratory test for all patients with suspected goiter; it guides subsequent testing (e.g., FT4/FT3 if TSH is low, TPO antibodies if TSH is high)【9】.
• Perform a high‑resolution thyroid ultrasound in every patient with a palpable nodule or clinical risk factors to characterize nodule size, composition, and sonographic risk features【9】.

Thyroid Scintigraphy

• Consider thyroid scintigraphy when serum TSH is suppressed or the gland is multinodular, especially in regions with prior iodine deficiency, to identify autonomously functioning nodules【9】.
• Routine scintigraphy is not required for the diagnosis of most goiters【9】.

Fine‑Needle Aspiration (FNA)

Size‑Based Recommendations

• Nodules <5 mm: monitor with serial ultrasound; biopsy is not indicated【9】.
• Nodules 5–10 mm with high‑risk ultrasound features (e.g., subcapsular or paratracheal location, suspicious lymph nodes, personal/family history of thyroid cancer, coexistent suspicious clinical findings such as dysphonia) may be biopsied or observed, depending on clinical judgment【10】.
• High‑risk lesions ≥10 mm: perform ultrasound‑guided FNA【10】.
• Intermediate‑risk lesions >20 mm: perform ultrasound‑guided FNA【10】.
• Low‑risk lesions: biopsy only if >20 mm and the nodule is enlarging or the patient has a relevant risk history【10】.

Special Considerations

• Do not biopsy nodules that are functionally “hot” on scintigraphy (functioning autonomously)【10】.
• Limit the number of biopsied nodules to a maximum of two in a multinodular gland【10】.
• For complex cystic‑solid nodules, target the solid, vascularized component for sampling【10】.

Medical Management

• Levothyroxine suppressive therapy is not recommended for benign nodular goiter【11】.
• Exceptions:
  
  • In areas with mild iodine deficiency, consider iodine supplementation and/or non‑suppressive levothyroxine for young patients with small nodules and high‑normal TSH【11】.
  • Young patients with subclinical hypothyroidism due to autoimmune thyroiditis should receive levothyroxine replacement【11】.
  • Levothyroxine should not be used to prevent recurrence after lobectomy when TSH remains within the normal range【11】.

Surgical Indications

• Surgery is indicated when the goiter produces clear local pressure symptoms (e.g., dyspnea, dysphagia) or when suspicious ultrasound features emerge despite a benign FNA result【11】.

Radioiodine Therapy

• Radioiodine is an option for hyperfunctioning or symptomatic goiters, particularly in patients with prior thyroid surgery, those at high surgical risk, or those who decline surgery【11】.
• Prior to radioiodine treatment, perform FNA on any coexistent cold (non‑functioning) nodules to exclude malignancy【10】.

Minimally Invasive Procedures

Percutaneous Ethanol Injection (PEI)

• PEI is the first‑line treatment for recurrent benign cystic thyroid lesions and is safe/effective for cystic or complex nodules with a large fluid component【11】【10】.
• PEI is not recommended for solid nodules (whether hyperfunctioning or not) or for multinodular goiters【10】.
• When treating complex lesions, obtain a sample of the solid component before PEI administration【10】.

Thermal Ablation

• Before laser or radiofrequency ablation of solid or complex nodules, repeat FNA to confirm cytology【10】.

Advanced Imaging

• Routine MRI or CT is not indicated for evaluation of thyroid nodules【10】.
• MRI/CT may be employed selectively to assess airway compression, substernal extension, or cervical lymph nodes not visualized on ultrasound【10】.

Follow‑Up of Benign Nodules

• Asymptomatic nodules with repeatedly benign cytology and no suspicious sonographic features may forgo routine surveillance imaging【11】.
• If a benign nodule develops suspicious clinical or ultrasound characteristics, repeat FNA is advised【11】.
• Nodules that increase in volume by >50 % or become symptomatic also warrant repeat FNA【11】.

Management of High‑Suspicion Thyroid Nodules in Patients with Suppressed TSH

Diagnostic Evaluation

Indications for Fine‑Needle Aspiration (FNA)

Management of Subclinical Hyperthyroidism (Hot Nodule)

FNA Technique and Cytology (Cold Nodule)

Surgical Decision‑Making Based on Bethesda Category

Critical Pitfalls to Avoid

Practical Algorithm (Key Steps)