After total thyroidectomy with or without radioactive iodine ablation, patients with papillary thyroid carcinoma may present with elevated thyroglobulin levels, revealing the presence of thyroid tissue in the body that indicates either residual tissue or locoregional/distant metastases.31 Metastatic lesions can be iodine-avid or not. The gene discussed is TG; the disease is thyroid gland papillary carcinoma.