SU22.4 | Thyroid Cancer — Summary & Reflection

KEY TAKEAWAYS

Thyroid cancer usually hides within an ordinary-looking nodule in a well patient, so the clinical features of malignancy — rapid growth, extremes of age, family history, prior irradiation, a hard fixed nodule, cervical nodes and signs of local invasion — must be sought deliberately (SU22.4). It is best understood as four separate diseases classified by cell of origin and differentiation: papillary (commonest, lymphatic spread, excellent prognosis), follicular (haematogenous spread, diagnosis needs histological capsular/vascular invasion not cytology), medullary (parafollicular C cells, calcitonin, MEN-2/RET), and anaplastic (elderly, rapidly lethal), with lymphoma as a rarer entity. Diagnosis follows the fixed nodule pathway of TSH, then ultrasound, then FNAC by Bethesda category, supported by calcitonin where medullary disease is suspected. Management is matched to type: surgery (lobectomy or total thyroidectomy, with neck dissection when indicated) is central; radioiodine and TSH-suppressive thyroxine benefit differentiated cancers only; medullary disease demands genetic testing, family screening and exclusion of phaeochromocytoma; and anaplastic disease is usually palliative.

REFLECT

Think back to the teacher in the opening scenario with a hard nodule and a palpable neck node. Which cancer does that picture most suggest, and why is its prognosis usually good despite the nodal spread? Now imagine the work-up returns a raised serum calcitonin instead — how would your whole plan change, including what you must do before operating and whom else you would investigate? Reflecting on how a single biochemical result can redirect the entire pathway is the habit that protects patients from both missed cancers and avoidable operative disasters.