The severity of lymphatic metastasis of thyroid cancer needs to be judged according to the specific situation of the patient. For example, whether it involves important organs, tissues, i.e. the extent of invasion, and so on. Thyroid cancer lymphatic metastasis most often occurs in zone 6. However, the severity cannot be judged solely on the basis of zoning. If the tumor has not invaded important organs or tissues, the situation is usually not serious, and surgery can be performed to remove the corresponding lymph nodes, which has a better therapeutic effect. If the tumor invades the esophagus, trachea, recurrent laryngeal nerve and other peripheral tissues, it is more difficult to expose the affected tissues during surgery, which makes it more difficult to treat the tumor, and it is easy to cause air embolism due to the air entering the bloodstream during the surgery, so the case is more serious.