From the Guidelines
To assess toxic multinodular goiter, a comprehensive approach is necessary, including thyroid function tests, imaging studies, and physical examination, as this condition can have significant impacts on morbidity, mortality, and quality of life.
Assessment Steps
- Perform a comprehensive thyroid function panel, including TSH, free T4, and free T3, to determine the degree of hyperthyroidism 1.
- Conduct a thyroid ultrasound to evaluate nodule size, characteristics, and vascularity, which is the best imaging study to evaluate thyroid morphology 1.
- Obtain a radioactive iodine uptake scan to assess nodule function, as it directly measures thyroid activity and can confirm the presence of toxic multinodular goiter 1.
- Consider fine-needle aspiration biopsy for nodules >1 cm or with suspicious features to rule out malignancy 1.
- Evaluate for compressive symptoms and perform a physical exam to check for visible or palpable goiter, as obstructive symptoms can be related to mass effect on the trachea or esophagus 1.
- Assess cardiovascular status, including heart rate and blood pressure, due to potential thyrotoxicosis effects, which can have significant impacts on morbidity and mortality.
- Screen for ophthalmopathy, although less common than in Graves' disease, as part of a comprehensive assessment.
Rationale
The approach outlined above allows for a thorough evaluation of thyroid function, nodule characteristics, and potential complications, guiding treatment decisions that may include antithyroid medications, radioactive iodine therapy, or surgery, depending on the individual case. The use of thyroid function tests, imaging studies, and physical examination is supported by recent evidence from the American College of Radiology 1, emphasizing the importance of a comprehensive assessment in managing toxic multinodular goiter.
From the FDA Drug Label
In patients with Graves’ disease with hyperthyroidism or toxic multinodular goiter for whom surgery or radioactive iodine therapy is not an appropriate treatment option. The assessment for Toxic Multinodular Goiter (TMG) is that methimazole tablets are indicated for patients with this condition when surgery or radioactive iodine therapy is not an appropriate treatment option 2.
- Key points:
- Methimazole is used to treat TMG
- Alternative treatments like surgery or radioactive iodine therapy may not be suitable for some patients
- Methimazole can be used to ameliorate symptoms of hyperthyroidism in preparation for other treatments.
From the Research
Assessment for Toxic Multinodular Goiter (TMG)
The assessment for Toxic Multinodular Goiter (TMG) involves several steps, including:
- Clinical evaluation to assess symptoms and overall health
- Laboratory tests, such as TSH, free thyroxine, and free triiodothyronine measurements, to evaluate thyroid function 3, 4, 5
- Imaging studies, including ultrasonography, chest radiography, and computed tomography, to assess goiter size, anatomy, and potential compression symptoms 4, 5
- Fine-needle aspiration biopsy (FNAB) to evaluate suspicious nodules and assess cancer risk 5, 6
Diagnostic Evaluation
Diagnostic evaluation for TMG should include:
- Patient history and physical examination to identify symptoms and potential complications
- Serum TSH determination to assess thyroid function
- Imaging studies to evaluate goiter size and anatomy
- FNAB to assess cancer risk in suspicious nodules
Treatment Options
Treatment options for TMG include:
- Surgery, which is often preferred for large goiters or those causing compressive symptoms 3, 7, 5
- Radioiodine (RAI) therapy, which is effective for many patients with TMG 3, 7, 5
- Antithyroid medications, which can control hyperthyroidism but are rarely used long-term 4
- Ethanol ablation, which is supported by level III evidence for patients unfit for surgery 7