The thyroid and lymph have a close relationship. Anatomically, the blood supply around the thyroid gland, including the arteries and veins, and the lymphatic vessels are parallel to each other. Thus the thyroid gland, on the basis of normal absence of morbidity, has little interconnection or influence through the blood supply and lymphatic return. It is only when thyroid cancer occurs that the relationship between the thyroid and lymph becomes significant. Because papillary cancer occurs in the thyroid gland and lymph node metastasis occurs at the earliest, when doing physical examination or reviewing thyroid ultrasound, it is necessary to check the thyroid gland in detail and at the same time, it is also necessary to conduct detailed examination of the lymph nodes in the region to see if there are any enlargement, metastasis, or recurrence of the lymph nodes. Therefore, patients with thyroid cancer must check the lymph nodes and the surrounding blood supply in detail.