Prognostic Relevance of Lymph Node Regression After Neoadjuvant Chemoradiation for Esophageal Cancer

Abstract

Prognostic factors after preoperative chemoradiation for patients with advanced esophageal cancer are under discussion. Treatment response measured in the primary tumor is a well-defined prognostic marker. The prognostic relevance of tumor regression in lymph nodes (LNs), eg, histomorphologic characteristics must be evaluated in a larger series of patients. From 1997-2010, 403 patients with cT3N×M0 esophageal cancer underwent preoperative chemoradiation followed by transthoracic esophagectomy. Histopathologic response of the primary tumor was graded in resected specimens as "minor" (≥10% vital residual tumor cells) or "major." The LNs of all patients without LN metastases (ypN0 n = 222, adenocarcinoma n = 129, squamous cell carcinoma n = 93) were reevaluated for central fibrosis. Univariate and multivariate analyses were performed on histomorphologic criteria of examined LNs and used to correlate these with tumor response and prognosis. The 5-year survival rate (5YSR) for all patients was 30%. Overall, 5480 LNs were reevaluated for the existence of central fibrosis in ypN0 cases. The prognostic relevance of the LN regression (LNR) grading system was confirmed for all patients with univariate (P < 0.001) and multivariate (P = 0.02) analyses. In results, the 5YSR for ypN0 patients overall was 37%, for patients with major response by the primary tumor was 42%, and for minor responders was 19% (P < 0.001). Analyzing LNR in major responders, the group with less than 3 LNs with central fibrosis (n = 52) showed significantly better prognosis (5YSR = 63%) compared to those with more (5YSR = 34%), (P = 0.016). Conclusion includes morphologic signs of metastatic LNR after chemoradiation, such as central fibrosis, are of prognostic relevance for patients with advanced esophageal cancer, especially for those with major response of the primary tumor.