What is the next step in managing a patient with a 3 cm thyroid mass that moves with swallowing and shows calcification on ultrasound (US)?

Proceed with ultrasound-guided fine-needle aspiration (FNA) biopsy immediately

The next step is ultrasound-guided fine-needle aspiration (FNA) biopsy of this thyroid nodule. This 3 cm mass with calcification meets multiple criteria that mandate tissue diagnosis regardless of other features.

Size-Based Indication for FNA

• Any thyroid nodule >1 cm warrants FNA, making this 3 cm nodule an absolute indication for biopsy 1
• Nodules ≥3 cm carry a 3-fold increased malignancy risk compared to smaller nodules, independent of other ultrasound features 1
• Guidelines from the American College of Surgeons and National Comprehensive Cancer Network specifically recommend evaluation of thyroid nodules larger than 2 cm, even without suspicious features, due to increased malignancy risk 1

Calcification as a High-Risk Feature

• Calcification within a solitary thyroid nodule carries a 75.7% risk of malignancy 2
• When calcification is present in a thyroid nodule, 59.2% of cases prove to be thyroid carcinoma on final pathology 2
• Microcalcifications are highly specific for papillary thyroid carcinoma 1
• The combination of large size (3 cm) plus calcification substantially increases overall malignancy risk 1

Critical Clinical Caveat

Surgery should be recommended regardless of FNA results when calcification is present in a solitary thyroid nodule 2. This is crucial because:

• False-negative FNA results occur in 11-33% of cases with worrisome clinical findings 1
• In one series, 24.1% of patients with calcified nodules and malignancy had preoperative FNA reported as benign 2
• A reassuring FNA should not override concerns when calcification is documented on ultrasound 1

Technical Approach

• Use ultrasound guidance for the FNA procedure, which allows real-time needle visualization, confirms accurate sampling, and is superior to palpation-guided biopsy for accuracy 1
• The nodule's movement with swallowing confirms it is thyroid tissue rather than an adjacent structure 1
• Ensure adequate sampling given the 21% nondiagnostic rate for nodules >3 cm 3

If FNA is Nondiagnostic

• Repeat FNA under ultrasound guidance if the initial sample is inadequate 1
• If repeat FNA remains nondiagnostic, proceed directly to surgical consultation given the high malignancy risk with calcification 2
• Most patients with nondiagnostic FNA have benign disease (86%), but the presence of calcification changes this risk profile dramatically 3

Additional Diagnostic Considerations

• Measure serum calcitonin as part of the workup to screen for medullary thyroid cancer, which has higher sensitivity than FNA alone 1
• Document TSH levels before FNA, as higher TSH is associated with increased risk for differentiated thyroid cancer 1
• Perform comprehensive neck ultrasound to assess for suspicious cervical lymphadenopathy 1