Effect of surgical approach on node harvest in gastrectomy: Analysis of the National Cancer Database.

Abstract

47 Background: Recent studies demonstrate significant surgical outcome advantages for patients undergoing minimally invasive versus open gastrectomy. Lymph node harvest at the time of gastrectomy is an indicator of adequate surgical resection and greater harvest is associated with improved staging and patient outcomes. Our aim is to evaluate lymph node harvest based on surgical approach. Our hypothesis is that a minimally invasive approach, particularly robot-assisted, will be associated with higher lymph node harvest. Methods: Patients undergoing gastrectomy for gastric adenocarcinoma in the period of 2010-2015 were identified using the National Cancer Database (NCDB). Data collected includes demographic data, institutional volume, approach, type of gastrectomy, tumor size, tumor location, pathologic T classification, year of diagnosis, Charlson-Deyo score and node harvest. Outcomes for patients undergoing open, laparoscopic, and robot-assisted gastrectomy were compared with univariate analysis and with a multivariate generalized linear mixed model (GLMM). Results: 19,555 patients were identified. There were 12,400 men (63.4%) and the mean age was 66.3 ± 12.5 years. 13,486 (69.0%) patients underwent open gastrectomy, 5,023 (25.7%) laparoscopic gastrectomy, and 1,046 (5.3%) robotic-assisted gastrectomy. Mean node harvest for open was 16.1 ± 11.5, laparoscopic was 15.1 ± 12.1, and robotic-assisted was 17.2 ± 13.3. Using a GLMM which controlled for the above listed covariates, robotic-assisted gastrectomy was associated with higher node harvest than both open (p = 0.041) and laparoscopic (p < 0.001) while open was associated with higher node harvest than laparoscopic (p < 0.001). There were 1582 operations with zero nodes harvested. In a sub-analysis of resections where at least one node was harvested (n = 17,973), the mean node harvest for open was 16.9 ± 11.1, laparoscopic was 17.5 ± 11.2, and robotic was 19.7 ± 12.3. Conclusions: This data suggests that a robot-assisted approach is associated with increased node harvest compared to laparoscopic and open approach in gastrectomy.