Knowledge of the risk of lymph node metastases is critical to planning therapy for T1 esophageal adenocarcinoma. This study retrospectively reviews 75 T1a and 51 T1b tumors and correlates lymph node metastases with depth of tumor invasion, tumor size, presence of lymphovascular invasion, and tumor grade.
Objectives: Increasingly, patients with superficial esophageal adenocarcinoma are being treated endoscopically or with limited surgical resection techniques. Since no lymph nodes are removed with these therapies, it is critical to have a clear understanding of the risk of lymph node metastases in these patients. The aim of this study was to define the risk of lymph node metastases for intramucosal and submucosal (T1) esophageal adenocarcinoma and to analyze factors potentially associated with an increased risk of lymph node involvement.
Methods: We reanalyzed the pathology specimens of all patients that had primary esophagectomy for T1 adenocarcinoma of the distal esophagus or gastroesophageal junction from January 1985 to December 2008. The prevalence of lymph node metastases was correlated with tumor size, depth of invasion, presence of lymphovascular invasion, and degree of tumor differentiation.
Results: There were 126 patients, 102 men (81%) and 24 women (19%), with a mean age of 64 (± 10) years. Tumor invasion was limited to the mucosa (T1a) in 75 patients (60%), whereas submucosal invasion (T1b) was present in 51 patients (40%). Tumors that had poor differentiation, lymphovascular invasion, and size ≥2 cm were significantly more likely to be invasive into the submucosa. Lymph node metastases were rare (1.3%) with intramucosal tumors but increased significantly with submucosal tumor invasion (22%)[P = 0.0003]. Lymph node metastases were also significantly associated with poor differentiation (P = 0.0015), lymphovascular invasion (P < 0.0001), and tumor size ≥2 cm (P = 0.01). Division of the submucosa into thirds did not show a layer with a significantly decreased prevalence of node metastases.
Conclusions: Adenocarcinoma invasive deeper than the muscularis mucosa is associated with a significant increase in the prevalence of lymph node metastases,and there is no "safe" level of invasion into the submucosa. Lymphovascular invasion, tumor size ≥2 cm, and poor differentiation are associated with an increased risk of submucosal invasion and lymph node metastases and should be factored into the decision for endoscopic therapy or esophagectomy