Pattern of lymph node metastases of esophageal squamous cell carcinoma based on the anatomical lymphatic drainage system

Abstract

The recent anatomical studies of the esophagus showed that submucosal longitudinal lymphatic vessels connect to the superior mediastinal and the paracardial lymphatics and lymphatic routes to periesophageal nodes originate from the muscle layer. Using clinical data for lymph node metastasis, we verify these anatomical bases to clarify the rational areas of lymph node dissection in esophageal cancer surgery. Analysis was performed on 356 consecutive patients who underwent esophagectomy with three-field dissection. Patients were divided into those with tumor limited within the submucosal layer and those with tumor invading or penetrating the muscle layer. Frequency of node metastasis was compared according to supraclavicular, upper mediastinum, mid-mediastinum, lower mediastinum, perigastric and celiac areas. In patients with tumor limited to the submucosal layer, node metastasis was more frequent in the upper mediastinum and perigastric area than the mid- or lower mediastinum. Even in patients with tumor located in the lower esophagus, node metastasis was more frequent in the upper mediastinum than the mid-mediastinum or lower mediastinum. In patients with tumor located in the mid-esophagus, node metastasis was more frequent in the supraclavicular area than the mid-mediastinum or lower mediastinum. In patients with tumor invading or penetrating the muscle layer, node metastasis in the mid- and lower mediastinum increased dramatically, but was still less frequent than those in the upper mediastinum or the perigastric area. Postoperative survival curves did not differ among the involved areas. The most predictive factor associated with lymph node metastasis for postoperative survival was not the area of involved nodes, but the number of involved nodes by multivariate analyses. These clinical results verify recent anatomical observations. The lack of difference in survival rates among the involved areas suggests that these areas should be staged equivalently. For adequate nodal staging, the upper mediastinum should be dissected for the lower esophageal tumor and supraclavicular areas should be dissected for the mid-esophageal tumor even in patients with tumor limited to within the submucosal layer.

Recurrent laryngeal nerve injury after esophagectomy for esophageal cancer: incidence, management, and impact on short- and long-term outcomes

“…The left RLN is longer than the right RLN and is situated close to lymph node stations 2L and 4L, consequently being more at risk for injury during lymph node dissection. Meticulous dissection of these stations is pivotal since there is a high frequency of lymph node metastasis (30)(31)(32). We experience robotic assistance of great value to perform a full paratracheal lymph node clearance, which was the standard of care for all these patients (33,34).…”

Computed Tomography–Based Distribution of Involved Lymph Nodes in Patients with Upper Esophageal Cancer

“…One reason for that variation could be the difference in T stage (depth of tumour invasion) of the primary tumour. It was reported that the positivity rate for locoregional nodes increases from 0% for intra-epithelial tumours to 31%-56% for T1b, 58%-78% for T2, 74%-81% for T3, and 100% for T4 tumours [14][15][16] .…”

“…In addition, our study observed only the distribution of metastatic lymph nodes. In fact, elective nodal irradiation should consider tumour T stage, histology, and tumour length, among other factors 15,16 . Despite those limitations, ct is an important and common tool for ec care in nonsurgical patients.…”

The extent of lymphadenectomy in esophageal resection for cancer should be standardized

“…For squamous cell carcinoma, there are a few large retrospective and prospective cohort studies, that describe the distribution pattern of lymph node metastases (3,9,11,13,27). Most patients in these studies have T3 cancers and almost 60% has positive lymph nodes.…”

“…The distribution pattern of lymph node metastases of esophageal cancer is unpredictable. Distribution of lymph node metastases may depend on tumor characteristics such as tumor location, histology, T-stage and the use of neoadjuvant therapy (9)(10)(11)(12)(13)(14). The surgical strategy should depend on the distribution pattern of nodal metastases but there is no worldwide consensus on the extent of lymphadenectomy.…”