Thyroid cancer accounts for 0.2%~1% of systemic malignant tumors, with a good prognosis and an overall 5-year survival rate >75%, divided into four types as follows.
1. papillary carcinoma, accounting for 60%, is more common in young people and is a malignant tumor with higher differentiation, i.e. low malignancy. 95% of patients with papillary carcinoma can survive for a long time as long as the treatment is properly chosen. Duan Shaobin, Department of Surgery, Xinjiang Uygur Autonomous Region Hospital of Traditional Chinese Medicine
2. Follicular carcinoma, accounting for 20%, is moderately malignant, common in middle-aged people, and hematogenous metastasis is predominant.
3. Undifferentiated carcinoma, accounting for about 5%-10%, is highly malignant and common in the elderly, often invading the esophagus and trachea when discovered, and metastasis occurs very early, which is often difficult to be removed when discovered.
4. Medullary carcinoma, with moderate malignancy, accounts for about 5%.
5. other accounts for 5%-10%, such as lymphoma, etc.
Surgical treatment modalities.
1 Papillary carcinoma should be treated with total excision of the affected gland lobe + isthmus + major excision of the opposite side. In case of microscopic carcinoma (mass <1cm) and the patient is less than 45 years old, total excision of the affected gland lobe only can be done.
2 For follicular adenocarcinoma, total excision on the affected side + isthmus + major excision on the contralateral side, or total lobectomy on both sides if the cancer is bilateral.
3 Undifferentiated carcinoma is mostly advanced when detected because of its rapid development and early metastasis, so it can rarely be removed cleanly. If the cancer is already in advanced stage, only radiotherapy and chemotherapy can be administered.
4 Medullary carcinoma is treated with bilateral total resection + bilateral central group lymph node dissection, or lateral lymph node dissection if there is lateral lymph node metastasis.
Problems of lymph node dissection.
1. Issues of lymph node dissection for papillary carcinoma: For microscopic papillary carcinoma, central zone lymph node dissection can be omitted, but at present most opinions still recommend central zone lymph node dissection because central zone lymph node dissection does not require extended incision, and the operation is simple and the damage is small. For papillary carcinoma >1 cm, it is currently recommended to routinely remove the central group lymph nodes, and if there is lymph node metastasis, to perform modified functional lymph node dissection or selective lymph node dissection.
2. If follicular carcinoma has no lymph node metastasis, prophylactic removal of central group lymph nodes is not performed because follicular carcinoma is mainly hematologic metastasis and lymphatic metastasis is rare; if there is lymph node metastasis, modified functional lymph node dissection or selective lymph node dissection is performed.
3. Papillary carcinoma or follicular carcinoma is routinely treated with thyroxine tablets (eugenol) orally after surgery to inhibit tumor recurrence. Most patients with stage II, all stage III and IV tumors can be treated with I131 if the tumor is >4 cm, invades blood vessels and envelope, or has lymph node metastasis, or if they are >45 years old (>45 years old is a high-risk group).
Frequently asked questions: I have found many irregularities in the surgical treatment of thyroid cancer.
Patients often ask me questions such as: (1) I have a right sided thyroid mass and my doctor performed a major right sided thyroidectomy. At that time, the intraoperative rapid freezing pathology said it was benign, but the postoperative pathology said it was cancerous. (2) I (patient 32 years old) have micro papillary thyroid cancer (7mm), my doctor did a total bilateral thyroidectomy, I am having hand twitching everyday (damage to parathyroid glands) what should I do? What should I do if my hands are twitching every day (damage to the parathyroid glands)? Is low calcium a sign that the parathyroid glands were cut out? Should I have a full bilateral thyroidectomy? (3) I had a goiter on my left side, and my doctor performed a major excision of my left thyroid gland. After the operation, I found that it was a micro papillary carcinoma, and the doctor said that no further surgery was needed.
The standard treatment is as follows
1. Some young patients have micro papillary thyroid cancer (mass <1cm), so total excision on one side, or total excision on one side + isthmus or total excision on one side + isthmus + large part on the opposite side is sufficient, but they have bilateral total excision, which is a blind expansion of surgery, prone to complications and reduces the quality of life.
2. Many patients have only lobectomy surgery without lymph node clearance, which is not standardized surgery. At least the central group of lymph nodes should be cleared (this is true for papillary, follicular and medullary carcinoma larger than 1 cm).
3. There are also many patients with insufficient surgical excision, such as papillary carcinoma >1cm, but only one side of the adenoid lobe was excised.
4. Some patients did not have intraoperative rapid cryopathological examination because they were operated as benign masses, or they had intraoperative rapid cryopathological examination but could not determine whether they were cancerous or not, but the postoperative paraffin pathological section confirmed cancer (this phenomenon exists because the accuracy of intraoperative rapid cryopathological examination is lower than that of postoperative paraffin pathological section). Then, if the first surgical excision was insufficient, another surgery should be performed. Go to remove enough glands as required, and choose whether to do central group lymph node dissection or selective lymph node dissection or perform modified functional lymph node dissection according to the situation, only then can we reduce tumor recurrence and prolong the survival time of patients. Many patients are worried about the damage of secondary surgery, but this worry is superfluous. Thyroid surgery is a body surgery, even if secondary surgery is performed, the damage is not significant and the recovery is faster.
Finally, thyroid cancer has a good prognosis. There are very few cases of undifferentiated carcinoma and medullary carcinoma in thyroid cancer with a poor prognosis. Most of them are papillary and follicular carcinoma with good prognosis, so patients should keep optimistic and face work and life like normal people.