RFA – Roberto Valcavi

Thyroid radiofrequency ablation (RFA)

The innovative therapy for the treatment of thyroid nodules

Thyroid nodules and RFA

Thyroid nodules are very common in the Italian population and are found more frequently in the female gender and, fortunately, they are in the majority of cases benign and do not require any treatment. The latter are generally diagnosed through an ultrasound of the neck, an examination that allows the thyroid gland and the characteristics of the nodules to be studied with extreme accuracy. In some cases, however, it may be necessary to perform a fine needle aspiration (a collection of cells with a fine needle) to obtain definitive confirmation of the nature of the thyroid nodule. In some cases, the thyroid nodules can become visible or annoying, as they compress the anatomical structures inside the neck, causing problems with swallowing or breathing.

Radiofrequency Thermo-ablation (RFA) is a minimally invasive treatment that is used as an alternative to surgery when this is not a good option for the patient. The treatment involves the introduction, Guided by Imaging Techniques (Tac or Ultrasound or CBCT), of a needle-electrode in the cancer lesion and the delivery of high-frequency energy that heats and destroys the cancer.

Medical skills

Prior to the intervention of thyroid RFA, laboratory tests must be carried out. Thyroid function and antithyroid autoantibodies, liver and kidney function tests, coagulation tests, ECG, motility of the vocal cords.Thyroid morphology is evaluated with ultrasound; in case of micropapillary cancer lymphatic metastases should be excluded. When the goiter is mediastinal CT and MRI are indicated. The nature of the nodule should be established by cytological examination on ultrasound aspiration (USG-FNAC) and/or with "core needle" (CNB) thyroid biopsy. Thyroid scintigraphy is indicated only in the case of hyper-functioning thyroid adenomas or hyper-functioning multinodular goiters.

PEI-EA vs RFA in thyroid cysts

Thyroid cysts / pseudocysts respond better to radiofrequency ablation than alcoholization. Radio frequency is the treatment of choice.

As an alternative to the surgical treatment of thyroid lobectomy or thyroidectomy, in the treatment of symptomatic benign thyroid cysts PEI (Percutaneous Ethanol Injection), or EA (Ethanol Ablation) has become popular in recent years. It is important to emphasize that the so-called thyroid cysts are not actually cysts but pseudocysts, and as such they retain a more or less abundant parenchymal component that continuously secretes the cystic fluid without solution.

For this reason, the simple drainage of pseudocystic thyroid lesions has proved largely ineffective. Ethanol reduces pseudocysts through direct coagulative necrosis, thrombosis of small vessels and finally tissue sclerosis.

After PEI / EA, relapses are frequent as the parenchymal component is always present even if scarcely visible with ultrasound. In fact, the tissue component of the pseudocyst can be compressed by the intracystic fluid, flattened against the walls of the pseudocyst, therefore scarcely visible in ultrasound. It is not destroyed by ethanol, while the radio frequency determines its abatement. Cases of ineffectiveness of PEI / EA with subsequent efficacy of RFA (Radiofrequency Ablation) have been reported.