Differentiated thyroid cancer includes papillary thyroid cancer and follicular carcinoma, of which papillary carcinoma accounts for more than 90%. The problem of irregularities in the surgical treatment of differentiated thyroid gland prevails in China. Due to the unbalanced economic development and lack of standardized training and other related factors in different parts of China, there are large regional differences in the level of treatment, as well as certain differences among hospitals and physicians. Although there are many problems in summary, this article only discusses the problems of thyroid cancer treatment that are currently common in hospitals above the tertiary level, hoping that through continuous standardization and improvement, it will serve as a model for primary hospitals to take the lead. There are three aspects in summary: 1. over-surgery of benign thyroid nodules; 2. problems in mastering total thyroidectomy technique; 3. insufficient scope of cervical lymph node dissection. 1, benign thyroid nodules excessive surgery problem population of the thyroid gland long nodules is very common, since the B ultrasound examination is commonly used in physical examination, the detection rate of thyroid nodules from the population of 4%, rapid rise of 19%, which is mainly female and elderly. Eighty to 90% of thyroid nodules are diagnosed as nodular goiter, which is a hyperplastic and degenerative disease of the thyroid tissue, not a tumor, and not an indication for surgery. Only about 5-10% are thyroid cancer, which requires surgery. Epidemiological and animal studies have confirmed that nodular goiter and thyroid cancer can occur together with persistent TSH increase due to low or high iodine; therefore, nodular goiter and thyroid cancer are “companion” rather than precancerous lesions. In addition, about 10% of other benign nodular diseases, such as Hashimoto’s thyroiditis and thyroid adenoma, usually do not require surgery. Currently, there is widespread overtreatment of thyroid nodules in China. According to a statistic of thyroid surgery in Changchun City, 9216 thyroid nodules were treated surgically, with malignant tumors accounting for only about 10% and benign nodules such as nodular goiter and adenoma accounting for about 90%. Because of the low level of ultrasound and cytology diagnosis in most hospitals in China, it is impossible to distinguish between benign and malignant nature before surgery, so some doctors operate on all patients with thyroid nodules, which not only wastes a lot of medical resources, but also causes different degrees of damage to the patients’ appearance and function. According to the standard procedure for the diagnosis of thyroid nodules established in Europe and the United States and our practical experience, it is recommended that fine needle aspiration cytology be performed on nodules of 1 cm or more detected by ultrasound. The disadvantages of surgery for nodular goiter include: permanent surgical scars left on the neck; most nodules are subject to recurrence; the possibility of long-term thyroxine use; the possibility of surgical sequelae; and the waste of valuable medical resources; of course, not all benign thyroid nodules do not require surgery. A few larger nodules may be considered for surgery if they 1. compress the trachea and affect breathing; 2. affect the appearance of the neck; 3. A nodule that falls into the chest and becomes a retrosternal goiter. Fine needle aspiration cytology of thyroid nodules is the most accurate and cost-effective diagnostic method for preoperative evaluation of the nature of thyroid nodules with a diagnostic accuracy of about 95% and is listed as routine in all foreign guidelines. In the United States, about 300,000 new thyroid nodules are diagnosed each year, and 96% of them are examined by puncture. However, in China, puncture is rarely performed due to old-fashioned physician beliefs, limitations in the level of cytopathological diagnosis, and excessive patient concern about thyroid nodules. According to the “Bartholomew Cytopathology Society”, the diagnostic strategy of thyroid aspiration is divided into six classes: malignant, suspected malignant, undiagnosed, atypical cells, follicular tumor, and benign, which are used to guide clinical treatment options. Whether thyroid puncture can lead to tumor implantation has been a major concern for patients. Since the majority of thyroid cancers are papillary and can generally be diagnosed based on cell morphology, fine needle aspiration is recommended, and coarse histologic aspiration is not recommended, which can significantly reduce the risk of implantation. In the literature, it has been reported that about 300,000 patients undergo thyroid FNA each year in the United States, and as of January 2010, the cumulative number of reported cases of thyroid puncture resulting in tumor implantation was only 19. Thus, the chance of fine needle puncture resulting in implantation is negligible and safe and feasible. Treatment and follow-up of thyroid nodules: In cases where thyroid puncture is diagnosed as benign, surgery can be avoided in most patients through clinical follow-up. A large sample of patients with benign thyroid nodules have a 0.6-3% chance of developing thyroid cancer during long-term follow-up and most of them can be detected and treated promptly during subsequent follow-up. According to our findings, the few thyroid cancers that are missed are mostly microscopic and can be observed or deferred for surgery. Diagnosis of benign nodules should be followed up with regular physical examination, TSH measurement and ultrasonography once a year for at least 3-5 years. Medication for benign thyroid nodules has no definite effect, and administration of levothyroxine does not make benign nodules smaller, but may bring about side effects in the heart and bones. Therefore, it is no longer recommended for routine use. No definite efficacy of Chinese herbs and proprietary Chinese medicines has been reported to be found either. In summary, the vast majority of thyroid nodules are benign and do not require surgery. Only 5-10% of malignant tumors need to undergo surgery. The key to identifying benign and malignant thyroid nodules is fine needle aspiration cytology diagnosis. In addition, most thyroid cancers are differentiated thyroid cancers with slow progression and excellent outcome, so there is no need to over-surgically treat all thyroid nodules. 2. The problem of mastering the technique of total thyroidectomy was firstly proposed by Halsted 107 years ago, the essence of which is to preserve the parathyroid glands through the technique of thyroid perineural dissection; unfortunately, this technique has not been mastered by most surgeons in China. The result is that the tumor is prone to recurrence and the patient has to undergo secondary or multiple surgeries. Therefore, the main problem in China is not excessive total thyroidectomy, but how to master the technique of total thyroidectomy. Should one side lobectomy or total thyroidectomy be performed for differentiated thyroid cancer? There are many international and especially domestic academic debates. We believe that through the debate, there is now a convergence of arguments that the extent of thyroidectomy should be determined according to the patient’s risk of recurrence. These risk factors include: (i) age ≥ 45 years, (ii) primary foci T3-4, (iii) distant metastases, (iv) male, and (v) papillary carcinoma grade II. At present, there are many risk grading schemes, and our department promotes the high and low risk method of Sloan-Kettering Oncology Center in the U.S. Their study found that the 20-year survival rate of the high-risk group is only 57%, but the low-risk group is as high as 99% and the medium-risk group is about 85%-88%. Therefore, for high-risk patients, a more aggressive total or near-total thyroidectomy with postoperative isotope therapy should be used to improve the patient’s chances of long-term survival. In contrast, patients without the above risk factors are recommended to undergo lobectomy of one thyroid gland plus isthmus, and isotope therapy is generally unnecessary. For intermediate-risk patients, total thyroidectomy or lobectomy with isthmus is not emphasized, and the surgeon can discuss the decision with the patient according to the situation, which is more in line with the current Chinese situation. Sloan-Kettering Cancer Center, USA Differentiated thyroid cancer treatment risk level grouping prognostic factors low risk group median group high risk group age age age age age gender female female male male male size range confined intra-glandular confined intra-glandular extra-glandular invasion extra-glandular invasion pathological grading papillary carcinoma papillary carcinoma follicular carcinoma follicular carcinoma distant metastasis none none technical key to total thyroidectomy is parathyroid gland preservation technique, not only to In addition to knowing the anatomical location and shape of the normal parathyroid glands, it is also necessary to grasp the blood supply of the parathyroid glands, to cut and ligate the small branching vessels close to the thyroid peritoneum, to preserve the parathyroid glands and blood supply in situ, and to perform parathyroid autotransplantation as soon as possible to ensure the survival of each parathyroid gland in case of blood flow problems. 90% of normal patients have 4 parathyroid glands, and a few have 3 or 5 parathyroid glands. The location of the superior parathyroid glands is relatively constant: about 77% are located near the cricothyroid joint, 22% are located behind the superior pole of the thyroid gland, and only about 1% are located behind the posterior pharynx and esophagus; the location of the inferior parathyroid glands is relatively variable: 42% are located behind the anterior pole of the thyroid gland, 39% are located in the thymus tongue, 2% are located in the superior mediastinal thymus, 15% are located in the tracheoesophageal groove near the body of the thyroid gland, and 2% have variations. The main shapes are oval, teardrop, pie, spherical, leafy, salami, rod and lentil. The size of the parathyroid glands ranges from 3 to 6 mm. The blood supply to the superior parathyroid glands usually comes from three sources: the posterior branches of the superior thyroid artery; individual blood supplies directly from the thyroid gland; and also from the inferiormost thyroid artery and anastomosing branch vessels. The blood supply to the inferior parathyroid gland usually comes from the inferior thyroid artery. The cause of permanent hypoparathyroidism after total thyroid cancer resection is related to the intraoperative removal of the parathyroid glands or impaired blood flow to the parathyroid glands. We found that the risk factors for permanent hypoparathyroidism were: accidental intraoperative parathyroidectomy, bilateral tracheoesophageal sulcus lymph node dissection, advanced thyroid cancer with focal perineural invasion, and whether the surgeon used a refined perineural dissection technique. It is important to identify and preserve the parathyroid glands in total thyroidectomy. We use a 2.5x magnification and headlamp illumination to perform a refined perineural dissection of the thyroid gland. We use the “superior thyroid decapitation technique” to separate and ligate the branches of the superior thyroid artery one by one and try to preserve the posterior branches of the superior thyroid artery, while the inferior thyroid artery is treated by preserving the main trunk and the upper and lower branches and cutting off the tertiary branches entering the true peritoneum of the thyroid gland, thus avoiding intraoperative ligation of the thyroid vessels and thus protecting The upper and lower parathyroid glands and their blood supply can effectively reduce permanent postoperative damage to parathyroid function. Therefore, it is crucial for the surgeon to be familiar with the anatomy and morphology of the parathyroid glands, to promote the technique of perineural dissection, and to treat each parathyroid gland strictly as the patient’s last parathyroid gland, whether it is lobectomy or total thyroidectomy. Insufficient cervical lymph node dissection Currently, thyroid cancer surgery is mainly performed by general surgeons and (otolaryngologic) head and neck surgeons. recurrence of lymph nodes in the neck, and patients face the challenge of reoperation. Happily, many hospitals have recently established specialized thyroid surgery, which can combine the strengths of two different specialties from the past and standardize neck clearance procedures. The American Society for Head and Neck Surgery and the American Academy of Otolaryngology-Head and Neck Surgery Foundation (ASHNS/AAO-HNS) jointly introduced the Cervical Lymph Node Division and Nomenclature System, which divides the cervical lymph nodes into six zones. This system was also updated in 2002 to divide zones I, II, and V into the middle A and B subzones. Cervical lymph node metastasis is common in papillary thyroid cancer, and the clinically identifiable metastasis rate is about 15-50%, while the literature reports that occult metastasis in cervical lymph nodes is about 50-80% of patients with clinically undetected lymph node metastasis (cN0) papillary thyroid cancer, and the occult metastasis rates in each zone are: 10-16% in zone II, 12-34% in zones III and IV, 5% in zone V, and 40-60% in zone VI. %-60%. Therefore, patients with cN0 have a higher risk of lymph node metastasis in zone VI, especially those with tumors larger than 1 cm or invaded by the perineurium are recommended for routine clearance; whether to routinely clear or observe microscopic cancers smaller than 1 cm is currently undecided. Other areas (I and V) are recommended for observation and follow-up due to the low metastasis rate. On the other hand, patients with clinically detected lymph node metastases (cN+) should undergo therapeutic neck debulking surgery. It has been found that the metastasis rates in cN+ patients are 2%-5% in region I, 45%-70% in region II, 55%-70% in region III, 40%-76% in region IV, 10%-20% in region V, and 60%-82% in region VI. Therefore, the neck clearance should include at least zones II-IV and VI. With further studies after subdivision, it was found that the metastasis rates in zones IIb and Va were low, ranging from 2%-20% and 5%, respectively, and in cases where cervical lymph node metastasis was not extensive, it was suggested that this area could be retained without clearance in order to reduce paraneoplastic nerve injury. In addition, the right paratracheal lymph nodes in VI area are divided into two groups, anterior and posterior to the laryngeal recurrent nerve, and the metastasis rate of the posterior group we found to be 32%, so it is recommended not to ignore the lymph node clearance of the posterior group of the nerve. Cervical lymph node dissection for thyroid cancer is recommended to preserve the normal structures of the neck, such as the sternocleidomastoid muscle, paramedian nerve, internal jugular vein, and cervical plexus nerve, etc. The following complications should be noted in the operation: 1. paramedian nerve palsy causing shoulder joint function syndrome; 2. injury to the mandibular rim branch of facial nerve causing angular deviation of the mouth; 3. vagus nerve injury causing hoarseness; 4. phrenic nerve injury causing diaphragm palsy; 5. thoracic duct injury Celiac leakage occurs; 6. Carotid artery injury causes hemorrhage or even hemiplegia. The thyroid surgeon needs special training and careful study in order to achieve a clean and complete lymph node dissection without damaging the many blood vessels and nerves in the neck. The problem of irregular treatment of differentiated thyroid cancer in China needs to be solved. There are three main aspects: 1. It is recommended to carry out ultrasound-guided fine needle aspiration cytology to reduce overtreatment of thyroid nodules; 2. to master the technique of thyroid perineural dissection to achieve safe and complete total thyroidectomy; 3. to learn and master the correct cervical lymph node dissection surgery and the scope of dissection to reduce lymph node recurrence.