What should you know about medullary thyroid cancer?

Medullary thyroid cancer develops from C cells, which make the hormone calcitonin, rather than from the thyroid cells involved in most other thyroid cancers. A neck lump, enlarged lymph nodes, cough, swallowing difficulty or a hoarse voice can occur, although symptoms vary. Blood tests may measure calcitonin and other markers, while ultrasound, scans and a tissue sample help define the diagnosis and extent. Some cases are linked with an inherited gene change, so genetic counselling and testing may be offered to the patient and relatives.

Treatment is planned by a specialist team after checking the thyroid, nearby lymph nodes and any distant spread. Thyroid removal surgery, often with removal of selected lymph nodes, is a common part of treatment when the cancer can be operated on. Radioactive iodine usually does not treat medullary thyroid cancer because its cells do not handle iodine in the same way as common thyroid cancer cells. Advanced or recurrent disease may be considered for targeted therapy. Follow-up uses examinations, scans and blood tests to watch for persistent or returning disease.

Seek urgent care for rapidly increasing neck swelling, difficulty breathing, inability to swallow fluids, or sudden severe weakness. Contact your treatment team about a new or worsening hoarse voice, persistent diarrhoea, flushing, bone pain or a neck lump. These symptoms do not establish the cause, but they warrant assessment in someone with known or possible thyroid disease.

Ask whether genetic counselling is appropriate, which surgery is planned, how calcitonin will be monitored, whether targeted therapy is relevant, and how follow-up will be organised for you and your family.