Abstract: Objective The of this study was to evaluate the correlation between maximum standard uptake values(SUV_max)of ¹⁸F-FDG PET/CT and BRAF mutation in patients with papillary thyroid carcinoma(PTC).Methods A total of 51 patients(mean age of 49.3±12.9 years)who underwent ¹⁸F-FDG PET /CT imaging and biopsy before thyroidectomy were retrospectively analyzed.Based on the pathological results,there were 48 patients with PTC and 3 patients with follicular thyroid carcinoma(FTC).The SUV_max of thyroid nodule was measured by semi-quantitative analysis.The correlation between clinical data(gender,age,tumor size and thyroglobulin concentration)and SUV_max was also analyzed.The difference of SUV_max between the two groups was analyzed by comparing the BRAF V600E mutation group and the non-mutation group.Results In patients with PTC,27 patients had BRAF V600E mutations and 11 patients had no tumor mutation.The SUV_max of BRAF V600E mutation group was significantly higher than that in the non-mutated group(5.5±3.9 vs. 2.2±1.2,P=0.002).The SUV_max of patients with tumor diameter ≥ 1cm was significantly higher than that in patients with tumor ＜1cm(P＜0.05).The SUV_max of patients with elevated thyroglobulin concentration was higher than that in normal patients(P＜0.05).No BRAF V600E mutation was observed in the FTC group.Conclusion The BRAF V600E mutant gene has a high SUV_max value in patients with PTC.There were significant difference in SUV_max among different tumor size and serum thyroglobulin concentration.

Key words: ¹⁸F-FDG PET/CT, Thyroid papillary carcinoma, Maximal standard uptake value, BRAF mutation