Impact of the number of examined lymph nodes on outcomes in patients with lymph node-negative gallbladder carcinoma

AIM To determine whether the number of examined lymph nodes(LNs) is correlated with the overall survival of gallbladder carcinoma(GBC) patients. METHODS Patients were collected from the Surveillance Epidemiology and End Results database(2004-2013) and categorized by the number of LNs into six groups: 1 LN, 2 LNs, 3 LNs, 4 LNs, 5 LNs, and ≥ 6 LNs. Survival curves for overall survival were plotted with a KaplanMeier analysis. The log-rank test was used for univariate comparisons.RESULTS In a cohort of 893 patients, the median number of examined LNs was two for the entire cohort. The survival for the 1 LN group was significantly poorer than those of the stage Ⅰ and Ⅱ disease groups and for the entire cohort. By dichotomizing the number of LNs from 1 to 6, we found that the minimum number of LNs that should be examined was four for stage Ⅰ, four or five for stage Ⅱ, and six for stage ⅢA disease. Therefore, for the entire cohort, the number of examined LNs should be at least six, which is exactly consistent with the American Joint Committee on Cancer criteria.CONCLUSION The examination of higher numbers of LNs is associated with improved survival after resection surgery for N0 GBC. The guidelines for GBC surgery, which recommend that six LNs be examined at least, are statistically valid and should be applied in clinical practice widely.

Stage Ⅲ should be subclassified into Stage ⅢA and ⅢB in the American Joint Committee on Cancer(8^(th) Edition) staging system for pancreatic cancer

AIM To ascertain the prognostic role of the T4 and N2 category in stage Ⅲ pancreatic cancer according to the 8 th edition of the American Joint Committee on Cancer(AJCC) classification.METHODS Patients were collected from the Surveillance Epidemiology and End Results(SEER) database(2004-2013) and were divided into three groups: T(1-3)N2, T4 N(0-1), and T4 N2. Overall survival(OS) and disease-specific survival(DSS) of patients were evaluated by the Kaplan-Meier method. RESULTS For the first time, we found a significant difference in OS and DSS between T(1-3)N2/T4 N(0-1) and T4 N2 butnot between T(1-3)N2 and T4 N(0-1). A higher grading correlated with a worse prognosis in the T(1-3)N2 and T4 N2 groups.CONCLUSION Patients with stage T4 N2 had a worse prognosis than those with stage T(1-3)N2/T4 N(0-1) in the 8 th edition AJCC staging system for pancreatic cancer. We recommend that stage Ⅲ should be subclassified into stage ⅢA [T(1-3)N2/T4 N(0-1)] and stage ⅢB(T4 N2).