Thyroid cancer affects the cells of the thyroid gland. The increase in the number of diagnosed cases is largely due to improved screening and more systematic removal of suspicious nodules. Thyroid cancers affect more women than men. Exposure to ionizing radiation during childhood (radioactivity, X-rays) is a risk factor, as is iodine deficiency. There are several types of thyroid cancer: differentiated, anaplastic and medullary.
- Differentiated cancers (papillary and follicular) are less invasive and the thyroid cells maintain their ability to absorb iodine. They represent the vast majority of thyroid cancers.
- Anaplastic cancers induce a change in the thyroid cells that causes a loss of function. These tumors are very aggressive and most frequently develop in the elderly.
- Medullary cancers are very rare and form in a type of thyroid cells called “parafollicular cells" or “C cells." These are not invasive most of the time.
How is thyroid cancer treated?
Thyroid cancer treatment almost always involves surgery. It consists of a total or partial thyroidectomy (removal of the gland), sometimes combined with removal of certain lymph nodes in the neck. After surgery, administration of radioactive iodine ensures the elimination of any remaining thyroid cells and reduces the risk of recurrence. Radioactive iodine treatment is not given in every case and depends on the stage of the disease. It is indicated in approximately 50% of cases. After total thyroid removal, the patient will need to take replacement thyroid hormones for the rest of their life (thyroxine, T4).
The cure rate for papillary, follicular and medullary cancers is higher than 80%, all stages included. Recurrences are rare and respond well to treatment combining surgery and radioactive iodine.
Early thyroid surgery for familial medullary cancers prevents their onset. This is why it is sometimes indicated in children. Treatment of pediatric patients (under 16 years of age) is provided jointly with the Pediatric Surgery Division at the HUG.