[Regulations and lymphadenectomy strategy of mediastinal and upper abdominal lymph node metastasis in thoracic esophageal carcinoma].

Background & Objective: Regional lymph node metastasis plays an important role in the prognosis of esophageal carcinoma. However, the range of lymph node dissection is still controversial. This study was to investigate the regulations of lymph node metastasis of thoracic esophageal carcinoma in the mediastinum and upper abdomen, and explore the rational lymphadenectomy with Ivor-Lewis procedure.

Methods: A total of 1 412 thoracic esophageal carcinoma patients underwent radical esophagectomy and mediastinal and abdominal lymphadenectomy by Ivor-Lewis procedure from 1990 to 2005 at Yangzhong People's Hospital; 517 of them underwent right para-trachea triangle field lymphadenectomy through the right pleural apical approach. The regulations of regional lymph node metastasis were analyzed.

Results: Of the 1,412 patients, 323 (22.88%) had postoperative complications, 2 (0.14%) died during hospitalization, and 547 (38.74%) had lymph node metastasis. The lymph node metastasis rates were 32.30% in the right para-trachea triangle, 18.43% in the upper mediastinum, 5.31% in the lower mediastinum, and 17.28% in the upper abdomen(P<0.001). Of the 13 916 resected lymph nodes, 2 662 (19.13%) were positive; the metastasis degree (positive lymph nodes/resected lymph modes) were 23.83% in the right para-trachea triangle, 18.92% in the upper mediastinum, 21.07% in the lower mediastinum, and 17.20% in the upper abdomen. For those patients with the cancer focuses in the upper, middle and lower segments of the esophagus, the lymph node metastasis rates were 40.59%, 36.97% and 44.35% (P=0.093), respectively, while the lymph node metastasis degree in these 3 fields were 19.60%, 18.35%, and 21.82%, respectively. Both the lymph node metastasis rate and degree were significantly higher in the patients at advanced stage than in the patients at early stage (46.56% vs. 7.75%, 21.82% vs. 4.01%, P<0.001).

Conclusions: Regional lymph node metastasis, especially in the right para-trachea triangle and upper mediastinum, is a key factor for thoracic esophageal carcinoma. Ivor-Lewis esophagectomy with two-field lymph node dissection is a safe operation for thoracic esophageal carcinoma, and may increase the chances of complete resection.