Comparative Quantitative Lymph Node Assessment in Localized Esophageal Cancer Patients After R0 Resection With and Without Neoadjuvant Chemoradiation Therapy.

INTRODUCTION: The effects of neoadjuvant chemoradiation therapy on lymph node retrieval during esophagectomy for patients with esophageal cancer are unclear. The aim of this study was to quantify lymph node retrieval after R0 esophagectomy and to assess its impact on overall survival in induction therapy patients.
METHODS: One hundred seventy-four consecutive patients underwent esophagectomy with or without induction therapy from 2008 to 2015 for esophageal cancer. Total lymph nodes, positive lymph nodes, and lymph node ratios were compared between two groups of patients: those treated with either upfront surgery or those treated with neoadjuvant chemoradiation therapy followed by surgery. Comparisons were made using Student's t test. Overall survival was obtained and compared using Kaplan Meier survival curves.
RESULTS: Total lymph node counts were less in the induction therapy group (p = 0.027), while positive lymph node counts and lymph node ratios did not differ between groups (p = 0.262 and p = 0.310, respectively). In the neoadjuvant chemoradiation followed by surgery group, overall survival was significantly shorter for patients who had any positive lymph nodes in the pathologic specimen (p = 0.0065).
CONCLUSIONS: Total lymph node counts were significantly lower in the induction therapy group, while positive lymph node counts and lymph node ratios did not differ from the upfront surgery group. Although overall survival was not different between groups, it was decreased within the induction therapy cohort among those who had any positive lymph nodes retrieved at surgery. This study confirms that unstratified gross lymph node counts do not substantially relate to prognosis in the heterogeneous population of locally advanced esophageal cancer patients who may or may not have had neoadjuvant chemoradiation.