Lymph Node Status After Resection for Gallbladder Adenocarcinoma: Prognostic Implications of Different Nodal Staging/Scoring Systems

Background and ObjectivesSeveral lymph node (LN) staging/scoring systems have been proposed to stratify the prognosis of patients with gallbladder adenocarcinoma (GBA). We sought to define the prognostic performance of the most commonly utilized LN staging/scoring systems including AJCC/UICC N stage, lymph node ratio (LNR), log odds (LODDS), and N score, among patients with GBA. MethodBetween 2004 and 2010, 1,124 patients with GBA were identified from the Surveillance Epidemiology and End Results (SEER) database. The discriminative ability of each LN staging/scoring system was assessed using the Akaike's Information Criterion (AIC) and the Harrell's concordance index. ResultsWhen assessed using categorical values, LNR had a modest, improved ability to discriminate patients with regard to prognosis (C-index: 0.615; AIC: 2118.2) compared with AJCC/UICC N stage or N score and a prognostic discrimination comparable to LODDS. Among patients who had a total number of LN examined (TNLE) of 1 or 2, all the staging/scoring systems performed comparably. In contrast, among patients who had 4 TNLE, LODDS performed the best (C-index: 0.613; AIC: 303.2). ConclusionThe performance of the different LN staging/scoring systems varied based on the TNLE. In particular, for patients who had 4 TNLE, LODDS out-performed the other staging/scoring systems. J. Surg. Oncol. 2015 111:299-305. (c) 2014 Wiley Periodicals, Inc