Correlation between F18-FDG PET/CT Imaging and BRAF V600E Genetic Mutation for the Early Assessment of Treatment Response in Papillary Thyroid Cancers

Abstract

In thyroid neoplastic pathology, the BRAF V600E mutation is shown to be involved in the oncogenesis of papillary thyroid cancer and its subtypes. The purpose of this study is to evaluate the correlation between the mutation of the BRAF V600E oncogene and the pathological standardized uptake values (SUV) at the F18-fluorodeoxyglucose (F18-FDG) positron emission tomography/computed tomography (PET/CT) evaluation, for a group of 20 patients with radically treated (total thyroidectomy and radioiodine therapy) papillary thyroid cancer, with subclinical persistent disease, at 6 months after the initial treatment. We analyzed the correlations between the values of SUV and the presence of the BRAF mutation as well with other prognostic factors such as stage, age, specific tumor markers (thyroglobulin and anti-thyroglobulin), extrathyroid extension, the presence of metastatic lymph nodes or distant metastasis. The value of SUV in the case of BRAF+ (positive) patients was higher than in the negative ones, but without statistical significance, thus, the values of the SUV cannot be a predictable factor for the presence of the genetic mutation. There was a statistically significant correlation in BRAF+ subgroup between the SUV values and the positive resection limit following surgery, showing a higher SUV value in the PET/CT evaluation. No correlation was observed between the aforementioned prognostic factors involved in papillary thyroid cancer and the BRAF V600E mutation.