First of all, the whole body, which is called in terminology a staged examination, a comprehensive examination, must be done. For example, a CT of the chest, an ultrasound of the abdomen, or more precisely, a CT of the abdomen, and a draw of markers, and so on. The most accurate test is PET, which is a kind of radioactive isotope labeled glucose, which is injected into the body, and all the places with increased metabolism will be visualized, so this is a more accurate test, but the cost is higher. Anyway, to determine whether there is metastasis, a systematic imaging examination of the whole body is needed.