Siewert J R, Stein H J
Chirurgische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, Germany.
Langenbecks Arch Surg. 1999 Apr;384(2):141-8. doi: 10.1007/s004230050184.
A complete tumor removal with an adequate safety margin in all three dimensions (the oral margin, the aboral margins and the tumor bed) must be the primary aim of any surgical approach to esophageal cancer. The same goal has to be achieved in the area of the lymphatic drainage. The safety margin of lymphadenectomy can be estimated by the so-called lymph-node ratio, i.e., the ratio between the number of positive nodes and removed nodes. Several studies have shown that, for esophageal carcinoma, a lymph-node ratio below 0.2 constitutes an independent prognostic factor. Although controlled trials are still lacking, these data suggest that extensive lymphadenectomy may thus improve the prognosis in patients at an early stage of lymphatic spread, i.e., patients with only lymph-node 'microinvolvement' or patients with a limited number of positive regional nodes on standard histopathologic assessment. In practice, this requires, as a minimum, a two-field lymphadenectomy. In patients with more advanced lymphatic metastases, two-field lymphadenectomy does not improve the prognosis and can only result in a reduction of local recurrences. A more extensive lymphadenectomy, i.e., three-field lymph-node dissection, increases the risk and morbidity of the surgical procedure, while a prognostic gain, if any, appears to be limited to a subgroup of patients with proximal tumors and less than five involved lymph nodes. Since, in the Western world, these patients are usually submitted to multimodal therapeutic protocols, extended three-field lymphadenectomy can currently not be recommended as standard therapy.
在三个维度（口腔切缘、远切缘和肿瘤床）均实现完整肿瘤切除并具备足够安全切缘，必须是任何食管癌手术方法的首要目标。在淋巴引流区域也必须实现同样的目标。淋巴结清扫的安全切缘可通过所谓的淋巴结比率来估计，即阳性淋巴结数量与切除淋巴结数量之比。多项研究表明，对于食管癌，淋巴结比率低于0.2是一个独立的预后因素。尽管仍缺乏对照试验，但这些数据表明，广泛的淋巴结清扫可能因此改善处于淋巴转移早期阶段的患者的预后，即仅存在淋巴结“微转移”的患者或在标准组织病理学评估中区域阳性淋巴结数量有限的患者。在实际操作中，这至少需要进行两野淋巴结清扫。对于有更晚期淋巴转移的患者，两野淋巴结清扫并不能改善预后，只会减少局部复发。更广泛的淋巴结清扫，即三野淋巴结清扫，会增加手术的风险和并发症发生率，而如果有预后获益的话，似乎仅限于近端肿瘤且受累淋巴结少于五个的患者亚组。由于在西方世界，这些患者通常接受多模式治疗方案，目前不推荐将扩大的三野淋巴结清扫作为标准治疗方法。
