It may also be considered in the following scenarios: i) as part of the initial staging process for cancers with invasive features, such as Hürthle cell carcinomas, in conjunction with other evidence of disease on imaging or elevated serum Tg levels, ii) as a prognostic tool for identifying lesions and patients at the highest risk for rapid disease progression and disease-specific mortality in the presence of metastatic disease, and iii) for evaluating posttreatment response following systemic or local therapy for metastatic or locally invasive disease [10,22]. The gene discussed is TG; the disease is metastatic neoplasm.