Thermal ablation of benign thyroid nodules

How it is performed

Thermal ablation treats the nodule without removing it. After local anaesthesia of the skin and of the thyroid capsule, a thin needle electrode is introduced under continuous ultrasound guidance and advanced into the nodule, usually through the isthmus of the gland, the route that keeps the needle away from the nerves and vessels of the neck. The energy, radiofrequency in the most studied technique, or laser or microwaves, heats the tissue to 60-100 °C and coagulates it; the needle is moved several times, treating small portions, until the whole nodule has been covered. The patient is awake and talks during the procedure, so the voice is checked at every moment. The treated tissue does not disappear immediately: it is reabsorbed over the following months and the nodule shrinks progressively, by about half within 1-3 months and by 70-80% within a year. The healthy thyroid around it keeps working normally.

Before the procedure

Thermal ablation is performed only on benign nodules: the guidelines require two fine-needle aspirations with a benign result, a recent ultrasound and thyroid hormone tests; if the nodule is hyperfunctioning, a scintigraphy is also needed. The nodule must cause symptoms or a real cosmetic concern: a benign nodule that causes no trouble should not be treated. The decision is made together with the endocrinologist, who follows the thyroid over time.

Does it hurt?

Local anaesthesia covers the skin and the thyroid capsule. During heating you may feel warmth or pain in the neck, sometimes radiating to the jaw or ear: at that point we pause and add anaesthetic, and in the Italian laser trial the procedure was well tolerated in 92% of cases. In the following days mild pain or swelling in the neck is normal and settles with common painkillers. In direct comparisons with open surgery, post-treatment pain scores were lower and the hospital stay shorter.

When another route is better

If the cytology is suspicious or indeterminate, surgery remains the right choice, because a complete histological examination is needed. In very large multinodular goitres, with several large nodules, surgery is usually more effective. For pure cysts, ethanol ablation is the first-line treatment, simpler and cheaper, with equivalent results in randomised trials. For hot nodules radioiodine is the first option; thermal ablation is considered mainly in young patients with small nodules who prefer to avoid radiation.

Further reading on the blog

When a benign thyroid nodule presses on the neck: can it be shrunk without surgery?

A feeling of pressure or of a lump in the throat, discomfort on swallowing, a swelling you can see in the mirror: a thyroid nodule can cause trouble even when it is benign. When symptoms are bothersome, surgery is often proposed. But there is an alternative: ultrasound-guided thermal ablation. Here is what the guidelines and the studies say, limits included.

Read the article

Risks, costs and opinions

The three questions patients ask most often before deciding, with clear answers.