TG and metastatic neoplasm: Using the modified 2009 ATA risk stratification system, patients can be classified as low, intermediate, or high risk (Table 1).2 A non-stimulated serum thyroglobulin value obtained about 6 weeks after surgery is also considered in the initial risk stratification system.2 A non-stimulated thyroglobulin above 5 ng/mL more than 6 weeks after a completion thyroidectomy would signal the clinician to look for the presence of residual normal thyroid tissue or metastatic disease that remains after surgery.