Thyroid nodules, goitre and thyroid cancer — viva

Stem

Examiner-led viva on a paediatric thyroid nodule. ^[1]

Examiner: What is your first investigation and why? ^[1]

Strong answer: TSH with reflex free T4 to establish functional status. A suppressed TSH with a solitary nodule suggests a hyperfunctioning lesion that is almost always benign and needs functional imaging, not FNA; a normal TSH never excludes malignancy, so it does not end the structural workup. ^{[1] [5]}

Examiner: How do you triage the nodule on imaging? ^[1]

Strong answer: High-frequency thyroid ultrasound applying the ACR TI-RADS system — scoring composition, echogenicity, shape, margin and echogenic foci into a tier TR1 to TR5 with size-based FNA thresholds — while mapping the cervical lymph nodes, because suspicious nodes are biopsied alongside the nodule. ^{[1] [2]}

Examiner: The FNA returns Bethesda III (indeterminate). What now? ^[1]

Strong answer: Apply molecular testing to detect fusion or mutation events that reclassify risk — children are dominated by gene fusions (RET/PTC, ETV6::NTRK3, ALK, BRAF fusions) rather than the BRAF V600E point mutation common in adults — and convene the multidisciplinary team to decide on lobectomy versus total thyroidectomy based on the molecular probability and family preference. ^{[1] [10]}

Examiner: Bethesda VI (malignant) with a positive central node. Who operates? ^[1]

Strong answer: A high-volume thyroid surgeon within a paediatric multidisciplinary thyroid team performs total or near-total thyroidectomy with central neck dissection, because complication rates — recurrent laryngeal nerve injury and hypoparathyroidism — are operator-dependent and lifelong in a child. ^{[9] [20]}