What is the initial approach for a male patient with a goiter (enlarged thyroid gland) and normal thyroid hormone levels, including Thyroid-Stimulating Hormone (TSH), free T4, and free T3?

Initial Approach for Euthyroid Goiter in Males

Thyroid ultrasound is the preferred first-line imaging modality to confirm the diagnosis, characterize the goiter morphology, and evaluate for suspicious nodules that may require biopsy. 1

Diagnostic Confirmation and Characterization

Initial Imaging Strategy

• Perform thyroid ultrasound as the primary diagnostic tool to confirm the neck mass originates from the thyroid gland and to document the size and morphology of the goiter 1
• If the goiter is nodular on ultrasound, evaluate each nodule for suspicious features including microcalcifications, irregular borders, central hypervascularity, and hypoechogenicity 1
• Consider CT neck (without contrast) if there are obstructive symptoms (dyspnea, orthopnea, dysphagia, dysphonia) to assess for substernal extension, retropharyngeal involvement, or degree of tracheal compression 1

When to Pursue Nodule Evaluation

• If nodules are identified on ultrasound, determine which require fine needle aspiration (FNA) based on size and ultrasound characteristics 1
• Suspicious ultrasound features that lower the threshold for biopsy include microcalcifications, irregular borders, central hypervascularity, and taller-than-wide shape 1
• The risk of malignancy increases approximately 7-fold if nodules are very firm, fixed to adjacent structures, rapidly growing, or associated with enlarged regional lymph nodes 1

Clinical Risk Stratification

High-Risk Features Requiring Aggressive Workup

• History of head and neck irradiation significantly increases malignancy risk and warrants lower threshold for nodule biopsy 1
• Family history of thyroid cancer or associated syndromes (familial adenomatous polyposis, Carney complex, Cowden's syndrome, MEN 2A/2B) substantially elevates cancer risk 1
• Male gender itself confers higher malignancy risk compared to females with similar nodular findings 1
• Age under 15 years or presence of vocal cord paralysis are particularly concerning features 1

Laboratory Considerations

• Radionuclide uptake and scan is not indicated in euthyroid patients with goiter, as it does not help determine malignancy risk or guide biopsy decisions 1
• The majority of nodules are "cold" on scintigraphy, and the majority of cold nodules are benign, resulting in low positive predictive value 1
• Consider measuring serum calcitonin if there is suspicion for medullary thyroid carcinoma based on family history or associated syndromes, though this remains controversial in routine practice 1

Management Algorithm Based on Goiter Type

Diffuse Goiter Without Nodules

• Observation is appropriate for asymptomatic diffuse goiter with normal thyroid function 1
• Consider levothyroxine suppressive therapy if the goiter is causing symptoms or cosmetic concerns, as studies show approximately 20% volume reduction after 6 months of treatment 2
• Patients with higher TSH levels (even within normal range) show greater volume reduction with levothyroxine therapy 2

Nodular Goiter

• Ultrasound evaluation of all nodules is mandatory to identify those requiring FNA based on size and suspicious features 1
• For multinodular goiter, compare ultrasound findings with radionuclide scan (if obtained) to identify hypofunctioning or isofunctioning nodules that should be targeted for biopsy 1
• Levothyroxine suppressive therapy shows variable response in nodular goiter: 31% of nodules show ≥50% volume reduction, 54% show 10-49% reduction, but some nodules are treatment-resistant 2

Critical Pitfalls to Avoid

• Never rely on radionuclide scanning alone to exclude malignancy in euthyroid patients, as the low positive predictive value of "cold" nodules makes this approach unreliable 1
• Do not assume normal thyroid function tests exclude the need for structural evaluation—goiter with normal hormones still requires imaging to assess for malignancy risk 1
• Avoid missing substernal extension by limiting evaluation to neck ultrasound alone when obstructive symptoms are present—CT provides superior assessment of deep extension 1
• FDG-PET/CT is not recommended for initial goiter evaluation and should not be ordered as part of the routine workup 1

Special Considerations for Males

• Male patients with thyroid nodules have inherently higher malignancy risk compared to females, warranting more aggressive evaluation of suspicious nodules 1
• Consider dietary iodine status in patients with restricted diets, as iodine deficiency can cause goiter even in developed countries, though this is extremely rare in North America 3
• If iodine deficiency is suspected based on dietary history (no dairy, seafood, or iodized salt intake), consider 24-hour urinary iodine excretion testing and radioactive iodine uptake scan, which would show diffusely increased uptake (>60-90%) 3