Neck Swelling and a Normal Fine Needle Aspiration
A 45-year-old woman is referred with a 2.5 cm firm right thyroid nodule found incidentally. She has no compressive symptoms, no hoarseness, and no family history of thyroid cancer. She had childhood neck irradiation for a benign condition. Ultrasound shows a solid hypoechoic nodule with irregular margins and microcalcifications, and a suspicious right level III lymph node. TSH is normal. Fine needle aspiration of the nodule is reported as Bethesda category II, benign. The lymph node was not sampled. She asks whether she can avoid surgery because the biopsy was benign.
1. How do you interpret the cytology in the context of the ultrasound and history, and what do you recommend?
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Cytology must be interpreted alongside ultrasound risk features and clinical history. Here there are multiple high-risk features: childhood neck irradiation, hypoechoic solid nodule with irregular margins and microcalcifications, and a suspicious cervical node. A benign cytology has a false-negative rate that is not negligible, and it does not sample the node. The correct recommendation is not simple observation. Options include repeat ultrasound-guided fine needle aspiration with on-site adequacy assessment, molecular testing if available, or diagnostic hemithyroidectomy. Given the suspicious node, sampling the node with ultrasound guidance and measuring thyroglobulin in the washout is reasonable. If malignancy is confirmed or strongly suspected, total thyroidectomy with central and possibly lateral neck dissection is planned. Discuss the rationale with the patient: a benign report reduces but does not eliminate the probability of cancer when imaging is highly suspicious. Document the discussion and the plan for multidisciplinary review.
2. She undergoes total thyroidectomy and central neck dissection. Final histology shows a 2.8 cm papillary carcinoma with 3 of 12 central nodes positive and extrathyroidal extension. How do you plan adjuvant therapy and surveillance?
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Risk stratification places her at intermediate to high risk depending on the extent of extrathyroidal extension and nodal burden. Plan for multidisciplinary discussion. Adjuvant radioactive iodine is generally considered for intermediate-risk and high-risk disease, after total thyroidectomy and adequate TSH stimulation. Before that, ensure adequate thyroid hormone withdrawal or recombinant TSH, low-iodine preparation, and pregnancy exclusion. Decide on the extent of any completion surgery if the lateral neck was not addressed and is now suspicious. Surveillance includes serum thyroglobulin and antithyroglobulin antibodies, neck ultrasound at intervals, and clinical review. Explain the rationale, the small risk of second malignancy, and the need for lifelong levothyroxine with dose adjustment. Avoid overstating certainty about benefit in intermediate-risk disease; discuss the trade-offs. Document the MDT recommendation.
3. What would you do differently if the cytology had been reported as Bethesda VI?
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If cytology were Bethesda VI with the same ultrasound findings, the diagnosis of papillary carcinoma would be established preoperatively. The plan would be total thyroidectomy with therapeutic central neck dissection, and assessment of lateral compartments by ultrasound and possibly cross-sectional imaging. The suspicious level III node would be sampled or addressed at surgery. Preoperative counselling would cover the diagnosis, staging, voice and calcium risks, and the possibility of radioiodine. The decision about the extent of surgery would be clearer, and the patient would not need a diagnostic hemithyroidectomy. The contrast illustrates how management depends on combining cytology, imaging, and history rather than on any single test.