Patterns of lymph node metastasis in 3-field dissection for carcinoma in the thoracic esophagus

Lymph node metastasis is well-known as the most important prognostic indicator for esophageal carcinomas, and an accurate assessment of positive metastasis can only be made after total lymphadenectomy around the esophagus. However, prior to the development of 3-field lymph node dissection in Japan, no such operation existed for ascertaining the full positivity distribution. We report herein the results of a retrospective study conducted on 70 patients who underwent subtotal esophagectomy with 3-field dissection to discover the patterns of lymph node metastasis from carcinoma in the thoracic esophagus. Lymph node metastases tended to have an orderly spreading pattern in relation to the tumor location, even though the lymph node metastasis varied widely from the lower neck to the upper abdomen. The nodes along the right recurrent nerve and the paracardiac nodes were most frequently found to be positive for metastasis. In contrast, no metastasis was found in the internal jugular nodes, the pretracheal nodes, the common hepatic nodes, or the splenic nodes. Patients with carcinoma in the upper thoracic esophagus rarely had metastasis in the abdominal nodes, while those with carcinoma in the lower thoracic esophagus rarely had metastasis in the cervical nodes. Thus, surgical extirpation of the lymph nodes during 3-field dissection is effective not only to determine the correct tumor staging for the planning of adequate adjuvant therapies postoperatively, but also to produce a guideline for prospective lymphadenectomy for esophageal carcinomas.