Percutaneous ablation holds the potential to substitute for surgery as first choice treatment for symptomatic benign thyroid nodules

Sir,

We read with interest the letter by Tez M. regarding our article recently published in International Journal of Hyperthermia entitled “Benign thyroid nodules treatment using percutaneous laser ablation (PLA) and radiofrequency ablation (RFA)” [1].

In his letter, Tez underlines the increasingly important role of RFA in the treatment of recurrent thyroid cancers and benign thyroid nodules. However, it should be noticed that PLA also has been widely and successfully used in the treatment of both recurrent thyroid cancers and benign nodular nodules [2–4]; currently, no clear evidence of superiority of one technique over the other is present in literature. Particularly, when dealing with a complex anatomical region as the neck, the smaller calibre of laser fibres, and the more precise energy deposition seems to represent a theoretical advantage of this technique over RFA. Moreover, it is difficult to understand from the present literature how much the result of ablation is influenced by the ablative technology (e.g. PLA or RFA) and how much by other factors, such as the experience of the operator in performing ablations. Furthermore, the application of the most recent image guidance modalities such as fusion imaging and contrast enhanced ultrasound might also influence the result of the treatment regardless the ablative technology used [5–8]. Thus, the aim of our work was to compare percentage volume reduction over time in patients with benign thyroid nodule treated with PLA or RFA by the same operators and with the same procedural technique. This was done to limit confounding variables that could affect the comparison of the two ablative technologies. In this scenario, our study demonstrated that PLA and RFA provide similar results in terms of volumetric reduction at 1, 6 and 12 months and similar complication rates when performed by operators with the same experience and with the same technique.

Next, Tez pointed out that the benign thyroid nodules may be treated by surgery or radioiodine. Surgery has historically been the best (and the only available) treatment option for symptomatic not-functioning nodules for a long time. However, open surgery has been largely supplanted by less invasive techniques in several field of medicine. Examples include coronary angioplasty and stenting, endovascular repair of aortic aneurysm, and image-guided liver and kidney tumour ablation. These procedures are often considered the first choice treatment rather than open surgery. Furthermore, it is our strong belief that the aim of the modern medicine should be not only to develop more effective technique for treating patients, but also to find treatments that are as minimally invasive as possible. This would allow not only to treat the relevant disease, but also to take care of the patient as a whole [9–11]. Particularly, in the treatment of benign thyroid nodules, percutaneous ablations have been largely demonstrated to achieve good control of compressive symptoms with very low complication rates, and provide the advantage of sparing the patient the invasiveness of standard surgery [3,12]. In our series, all the patients reported a clinically significant improvement in symptoms or cosmetic problems after the procedure, that was sustained up to one year.

Further, Tez points out the reported risk of micropapillary thyroid carcinoma in the context of a multinodular goitre. This is a very well-known problem, but the best management of patients with multinodular goitre is still debated. Should we perform multiple fine needle aspiration of each single nodule in the patients with multinodular goitre in order to exclude the presence of an occult micropapillary tumour? Should we offer total thyroidectomy to all the patients with multinodular goitre, even if asymptomatic, as a micro-papillary tumour might be present? Notably, the real clinical implication of a micro-papillary thyroid carcinoma is still to be defined, as often these tumours will never progress during the life of a patient. Thus any kind of treatment might represent an overtreatment [13]. The problem of overtreatment of thyroid cancer is so relevant, that some authors have provocatively proposed to turn off US machines in order not to even detect not-palpable thyroid nodules [14].

Finally, Tez questioned the relevance of our study [1], as no predefined criteria for allocating patients to one treatment group or the other were defined. This is of course one of the major limitations of the present study, as is typical of retrospective series. The purpose of this report is to suggest the potential merits of a prospective trial, not to prove superiority of one treatment vs. the other. Prospective studies with randomisation of patients to PLA or RFA treatment would be necessary to further clarify the topic. To the best of our knowledge, our study is the first comparing the result of PLA and RFA when performed by the same operators with the same technique. Our study reported no significant difference in volume reduction over time between the two technologies, when the approach is identical between the two ablative methods. Design of future clinical trials should keep this concept in mind. To be specific, such trials might best be designed so that both methods are delivered by each participating investigator, using identical methods (e.g. same imaging device, etc.).

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.