In the history of thyroid cancer treatment, cervical lymph node dissection is often inseparable from radical cervical lymph node dissection.This procedure involves the removal of the lymphoid tissue in the neck and the surrounding fat, muscles, nerves, blood vessels, etc.Also known as radical neck dissection, total neck dissection, radical cervical lymph node resection, etc.

There are four different methods of cervical lymph node dissection, including radical cervical lymphadenectomy, functional (modified) cervical lymphatic dissection, selective lymphadenectomy, and central lymphadenectomy.At present, central lymph node dissection and functional neck lymph node dissection are more commonly used in surgery.

淋巴系统是人体内重要的防御系统，它遍布在全身各处，可产生杀伤因子和直接杀灭细菌、病毒甚至癌细胞。当人体组织有癌细胞时，淋巴细胞会聚集在癌细胞周围，吞噬杀伤癌细胞。但是由于癌细胞的异质性，有着顽强的生命力，即使被淋巴细胞吞噬了也依旧能存活。而淋巴细胞有时像血细胞一样在淋巴系统内循环。这样，本来是杀伤癌细胞的淋巴细胞，反而成了帮助癌细胞扩散的便利通道。与其它肿瘤一样，甲状腺癌细胞容易经过淋巴转移，沿途的淋巴结就成为癌细胞的中转站和庇护所。颈部中央区淋巴结往往是转移的第一站，随后可能转移到侧颈部、以及更远处的淋巴结。此时，即便切除了全部腺体组织，淋巴结里的癌细胞也已经埋下了转移和复发的种子。所以，淋巴组织作为较常出现转移的部位，在手术中进行清扫也是无可非议的，可以尽早的发现散落的癌细胞，这样有助于尽快的预防转移。把淋巴结清扫干净，才能最大限度的降低癌细胞的复发和转移。淋巴结清扫的目的，就是彻底清除癌细胞可能潜伏的哨点。

The cervical lymph nodes are very abundant. The American Joint Committee on Cancer has divided the cervical lymph nodes into seven zones, which is of great significance for clinical diagnosis. The border is basically the vascular sheath of the carotid artery. The medial side of the carotid sheath belongs to the Central District, while the lateral side belongs to the lateral neck region. Lymph node dissection in the Central District is a routine procedure, and even in earlier thyroid cancer, the risk of occult metastasis in the Central District is higher. There are even about 30% to 50% of patients, in the preoperative or intraoperative examination did not find lymph node metastasis, but postoperative pathology found metastasis. Therefore, the domestic opinion tends to recommend ipsilateral prophylactic lymphadenectomy in the Central District, even in the absence of lymph node metastasis on preoperative evaluation. But like follicular carcinoma, because it has very little chance of lymph node metastasis, so can not do routine cleaning.

Lateral neck dissection is not recommended if metastases are not suspected because of the relatively low incidence of metastasis and the relatively large surgical trauma. At present, it is generally accepted that lymph node dissection should be performed only if the preoperative examination is highly suspected or confirmed the presence of lateral cervical lymph node metastasis. Radical neck dissection is very important for the prognosis of thyroid cancer patients. The more radical the dissection, the better the prognosis. This is because lymph node dissection reduces the risk of thyroid cancer recurrence and metastasis and prolongs patient survival. However, non-standard cleaning not only increases the possibility of recurrence, but also brings great difficulty to the second operation and increases the chance of operative complications