Medullary undershooting of lymph nodes in the neck 2 years after thyroid cancer surgery is usually abnormal. If the medullary undershooting of lymph nodes in the neck is found 2 years after thyroid cancer surgery, it may be caused by recurrence of thyroid cancer, malignant transformation of lymph node tissues, and other abnormal symptoms such as low-grade fever, fatigue, and pain in the neck. If the medulla oblongata of the lymph nodes in the neck is found in the postoperative examination of thyroid cancer, it is better to carry out pathological biopsy in time to further clarify the diagnosis, and consider another surgery to remove the diseased tissues if necessary. The lack of clear medulla in the lymph nodes in the neck 2 years after thyroid cancer surgery may be caused by recurrence of thyroid cancer or metastatic spread of cancer cells, so it is necessary to consult a doctor in time for examination and receive regular treatment so as not to delay the condition and cause serious consequences.