Prognostic significance of the endoscopic ultrasound defined lymph node metastasis count in esophageal cancer.

The key prognostic factor which predicts outcome after esophagectomy for cancer is the number of malignant lymph node metastases, but data regarding the accuracy of endoscopic ultrasound (EUS) in determining and predicting the metastatic lymph node count preoperatively are limited. The aim of this study was to assess the prognostic significance of EUS defined lymph node metastasis count (eLNMC) in patients diagnosed with esophageal cancer. Two hundred and sixty-seven consecutive patients (median age 63 years, 187 months) underwent specialist EUS followed by stage directed multidisciplinary treatment (183 esophagectomy [64 neoadjuvant chemotherapy, 19 neoadjuvant chemoradiotherapy], 79 definitive chemoradiotherapy, and 5 palliative therapy). The eLNMC was subdivided into four groups (0, 1, 2 to 4, >4) and the primary measure of outcome was survival. Survival was related to EUS tumor (T) stage (P < 0.0001), EUS node (N) stage (P < 0.0001), EUS tumor length (p < 0.0001), and eLNMC (P < 0.0001). Multivariable analysis revealed EUS tumor length (hazard ratio [HR] 1.071, 95% CI 1.008-1.138, P= 0.027) and eLNMC (HR 1.302, 95% CI 1.133-1.496, P= 0.0001) to be significantly and independently associated with survival. Median and 2-year survival for patients with 0, 1, 2-4, and >4 lymph node metastases were: 44 months and 71%, 36 months and 59%, 24 months and 50%, and 17 months and 32%, respectively. The total number of EUS defined lymph node metastases was an important and significant prognostic indicator.