PET-CT in anaplastic thyroid carcinoma and other aggressive histological subtypes

[EN]Introduction and objective: The aggressive histological subtypes of thyroid cancer are less common and have a worse prognosis than well –differentiated ones (DTC). The most important aggressive subtypes are Hürtle cell carcinoma (CHH), anaplasic and poorly differentiated carcinoma. In this review, we are going to evaluate the role of PET-CT, especially with 18F-FDG, in these aggressive histological lines, as well as in aggressive subtypes of DTC (tall cells, diffuse sclerosing…) and in radioiodine-refractory differentiated thyroid carcinoma. Synthesis: Although the main indication for 18F-FDG PET in thyroid cancer is suspected recurrence, in patients with DTC with elevated serum thyroglobulin and radioiodine-negative whole-body scan (WBS), this technique has increasing applications in DTC. Likewise, 18F-FDG PET is also an efficient diagnostic tool in the study of anaplastic carcinoma, poorly differentiated and other aggressive lines It is recommended, in current clinical guidelines, as part of the initial staging in anaplastic, poorly differentiated, and invasive HCC. And it is increasingly used in other indications such as prognostic assessment, evaluation of treatment response, and even during the follow-up of high-risk patients. It is recommended, in current clinical guidelines, as part of the initial staging in anaplastic, poorly differentiated, and invasive HCC. And it is increasingly used in other indications such as prognostic assessment, evaluation of treatment response, and even during the follow-up of high-risk patients. The use of other PET tracers, such as 68Ga-PSMA and 68Ga-DOTATATE have not clearly demonstrated their clinical benefit over 18F-FDG. They are usually limited to cases in which it is necessary to assess the density of somatostatin analogs and PSMA receptors prior to metabolic therapy. Conclusions: 18F-FDG PET-CT is the most effective functional diagnostic technique in the study of poorly differentiated and aggressive thyroid neoplasms, since they show little or no avidity for radioiodine and however high affinity for 18F-FDG. The role of other PET tracers for the evaluation of these tumors is promising, although it still needs studies with a larger number of patients. t is recommended, in current clinical guidelines, as part of the initial staging in anaplastic, poorly differentiated, and invasive HCC. And it is increasingly used in other indications such as prognostic assessment, evaluation of treatment response, and even during the follow-up of high-risk patients. 18F-FDG PET-CT is the most effective functional diagnostic technique in the study of poorly differentiated and aggressive thyroid neoplasms, since they show little or no avidity for radioiodine and however high affinity for 18F-FDG. The role of other PET tracers for the evaluation of these tumors is promising, although it still needs studies with a larger number of patients

PET en el diagnóstico de la patología de tiroides

Introduction and objective: PET/CT is a technique which oncological indications are now increasing, being thyroid cancer one of them. Method: narrative review. Comment: The present study is a review of well-known indications, as well as those fields in which more studies are needed to establish the utility of this technique in every kind of malignant thyroid pathology.Introducción y objetivo: La PET/TC es una técnica cuyas indicaciones en Oncología se encuentran en expansión y el cáncer de tiroides es una de ellas. Método: Revisión narrativa. Comentarios: En el presente artículo se revisan las indicaciones establecidas hasta la fecha, así como aquellos campos en los que son necesarias investigaciones adicionales que permitan establecer la utilidad de esta técnica en los distintos tipos de patología maligna tiroidea