What is the management approach for an adult patient with an enlarged heterogeneous thyroid gland due to goiter, potentially from an area with iodine deficiency or a family history of thyroid disorders?

Management of Enlarged Heterogeneous Thyroid Gland Due to Goiter

For an adult with an enlarged heterogeneous thyroid gland due to goiter, begin with TSH measurement, followed by thyroid ultrasound, and reserve treatment for those with compressive symptoms, cosmetic concerns, or thyroid dysfunction—otherwise observation is appropriate. 1, 2

Initial Diagnostic Approach

Start with TSH measurement before ordering any imaging studies. 2 This determines whether the goiter is toxic (hyperthyroid), nontoxic (euthyroid), or associated with hypothyroidism, which fundamentally changes management. 3, 4

• Thyroid ultrasound should be performed in all patients with goiter as it has become an extension of physical examination. 1, 3 Ultrasound determines thyroid dimensions, evaluates nodule characteristics, identifies suspicious features requiring biopsy, and assesses for substernal extension. 1, 2

• If TSH is suppressed (low), obtain a radioiodine uptake scan to differentiate toxic multinodular goiter from other causes of hyperthyroidism like Graves disease. 1, 2

Risk Factor Assessment

Given the context of potential iodine deficiency or family history, recognize that:

• Iodine deficiency affects 500-600 million people worldwide and greatly enhances multinodular goiter incidence, with severe deficiency causing both goiter and hypothyroidism while increasing risk of autonomous nodules. 5

• Female sex and advancing age are significant non-iodine dependent risk factors, with typical development in women during their fifth and sixth decades. 5, 2

• Family history of thyroid disease increases risk for both hypothyroidism and goiter development. 1

Management Based on Clinical Presentation

For Asymptomatic Nontoxic Multinodular Goiter

Observation is recommended for asymptomatic non-toxic multinodular goiter. 2 Many simple multinodular goiters in adults can benefit from simple monitoring without intervention. 6

For Symptomatic Goiter

Surgery is indicated for patients with compressive symptoms such as dyspnea, orthopnea, dysphagia, or dysphonia. 2, 7 Several studies have demonstrated improved breathing and swallowing outcomes after thyroidectomy. 7

• Total thyroidectomy is now preferred over subtotal thyroidectomy as it provides immediate, permanent cure with no recurrences. 2

• Surgery is particularly indicated for substernal extension, as radioactive iodine is less effective and surgery provides definitive decompression. 2

• Refer to high-volume thyroid surgeons (performing >100 thyroidectomies annually) who have complication rates of 4.3% versus 4-fold higher rates for low-volume surgeons. 2

For Cosmetic Concerns

Surgery is recommended for cosmetic concerns when the goiter is unsightly or causes significant patient distress. 2, 6

For Toxic Multinodular Goiter

Do not rely on prolonged antithyroid drug therapy for toxic multinodular goiter expecting remission, as these represent autonomous hyperfunctioning nodules rather than autoimmune stimulation. 2 Treatment options include:

• Radioactive iodine ablation constitutes an alternative to surgery, especially for voluminous, compressive, hyperfunctional goiters in older patients. 6

• Surgery remains definitive treatment for toxic multinodular goiter when remission is not expected with medical therapy. 2

Addressing Iodine Deficiency

If iodine deficiency is confirmed as the underlying cause, iodine supplementation is appropriate. 3 However, implementation of iodine prophylaxis programs has met with considerable technical and socioeconomic difficulties. 8

• Iron and selenium deficiency should also be evaluated, as iron deficiency impairs thyroid metabolism and selenium deficiency affects deiodination of T4 to T3. 5

Common Pitfalls to Avoid

• Do not order imaging before checking TSH levels, as this wastes resources and doesn't guide initial management appropriately. 2

• Avoid thyroxine suppression therapy for iodine-sufficient multinodular goiters, as most grow by mechanisms other than increased TSH stimulation, making suppression inefficient and potentially causing complications. 8

• Be aware that permanent hypocalcemia occurs in 1.1-3% of patients after thyroidectomy, requiring careful postoperative monitoring. 2

• Recognize that recurrence rates after thyroidectomy are 10-19% for iodine-sufficient goiters, though total thyroidectomy has eliminated recurrences compared to subtotal approaches. 2, 8