Clinical impact of lymphadenectomy extent in resectable esophageal cancer.

Esophageal cancer (EC) frequently presents with advanced stages and is associated with high recurrence rates after esophagectomy. The value of an extended lymph node dissection (ELND) remains unclear in this setting. An EC data set was created from the Surveillance, Epidemiology, and End-Results 1973-2003 database. Relationships between the number of lymph nodes (LNs) examined and overall survival (OS) were analyzed. From a cohort of 40,129 EC patients, 5,620 individuals were selected. The median age was 65 (range: 11-102), and 75% were men. The median tumor size was 5.0 cm (0.1-30). On multivariate analysis, total LN count (or negative LN count, respectively) was an independent prognostic variable, aside from age, race, resection status, radiation, T category, N category (all at p < 0.0001), and M category (p = 0.0003). Higher total LN count (>30) and negative LN count (>15) categories were associated with best OS and lowest 90-day mortality (p < 0.0001). The numeric LN effect on OS was independent from nodal status or histology. Greater total and negative LN counts are associated with longer EC survival. Although the mechanism remains uncertain, it does not appear to be limited to stage migration. ELND during potentially curative esophagectomy for EC can be supported by the data.