Survival after resection of appendiceal carcinoma by hemicolectomy and less radical than hemicolectomy: a population-based propensity score matched analysis.

Background The operative treatment for non-metastatic appendiceal carcinoma is controversial despite the recommendation of right hemicolectomy by many researchers. The aim of this population-based study was to compare outcomes after right hemicolectomy (RH) and less radical resection than right hemicolectomy (LRH). Methods A total of 1144 patients who underwent resection with additional lymphadenectomy of stage I-III appendiceal carcinoma from 2004 to 2012 was identified in the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific survival (CSS) after RH and LRH were assessed by unadjusted and risk-adjusted Cox regression analysis and by propensity score matched analysis. Results A total of 855 (74.7%) patients underwent RH, and 289 (25.3%) underwent LRH. In an unadjusted analysis, survival after LRH and RH did not differ in OS (HR=0.95, 95%CI: 0.71−1.27, P=0.707) and CSS (HR=0.95, 95%CI: 0.68−1.32, P=0.762). The 5-year OS and CSS in patients who underwent RH were 71.6% (95%CI: 67.8-75.6%) and 76.4% (95%CI: 72.8-80.3%) compared with 73.8% (95%CI: 67.9-80.2%) and 78.7% (95%CI: 73.2-84.7%) in patients with LRH, respectively. No relevant difference in survival between LRH and RH could be observed in a multivariable analysis (OS: HR=0.90, 95%CI: 0.65-1.25, P=0.493 and CSS: HR=0.87, 95%CI: 0.60-1.26, P=0.420) and after propensity score-adjusted analysis (OS: HR=0.87, 95%CI: 0.62−1.22, P=0.442 and CSS: HR=0.97, 95%CI: 0.67−1.40, P=0.883). Conclusions In this retrospective analysis, survival after RH for non-metastatic appendiceal carcinoma was not statistically significantly superior to LRH. Hence, LRH with lymphadenectomy might be sufficient for treatment of non-metastatic appendiceal carcinoma. This article is protected by copyright. All rights reserved.