Molecular Markers Are Associated with Onset of Radioiodine Refractoriness in Patients with Papillary Thyroid Carcinoma.

The onset of radioiodine-refractory thyroid carcinoma (RR-TC) is a negative predictor of survival and has been linked to the presence of BRAFV600E mutations in papillary thyroid cancer. We aimed to identify further genetic alterations associated with RR-TC. Methods: We included 38 patients with papillary thyroid cancer who underwent radioiodine imaging and 18F-FDG PET/CT after total thyroidectomy. The molecular profile was assessed by next-generation sequencing. The time to the onset of RR-TC for different genetic alterations was compared using the log-rank test. Results: The median onset to RR-TC was 0.7 and 19.8 mo in patients with and without, respectively, telomerase reverse transcriptase promoter mutations (P = 0.02) and 1.7 and 19.8 mo in patients with and without, respectively, a tumor protein 53 mutation (P < 0.01). This association was not observed for BRAFV600E mutations (P = 0.49). Conclusion: Our data show a significant association between the onset of RR-TC and mutations in telomerase reverse transcriptase promoter and tumor protein 53, indicating the need for a more extensive diagnostic workup in these patients. Certain genetic changes put patients with thyroid cancer at risk of developing cancer spread that does not respond to radioiodine therapy.