Association between lymph node examination and nodal staging for pancreatic adenocarcinoma: A population-based analysis.

作者：Xu, Rui-Hua; Wang, Zi-Xian; Qiu, Miaozhen; Jin, Ying; He, Ming-Ming; Wang, Feng; Wang, Fenghua

来源：53rd Annual Clinical Meeting of the American-Society-of-Clinical-Oncology (ASCO), Chicago, IL, 2017-06-02 To 2017-06-07.

DOI：10.1200/JCO.2017.35.15_suppl.e15772

<jats:p> e15772 </jats:p><jats:p> Background: The minimum number of examined lymph nodes (ELNs) for accurate nodal staging remains controversial and has not been recommended by the NCCN guidelines for pancreatic adenocarcinoma (PADC). We aimed to evaluate the time trends in the ELN count and the proportion of node-positive PADC (N+%), as well as determine the minimal threshold for the ELN count. Methods: We analyzed 9258 patients with resectable PADC between 2000 and 2012 in the SEER database (18 registries). Changes in the ELN count and N+% over time were evaluated using the Spearman correlation analysis and the Cochran-Armitage test, respectively. Multivariable logistic and Cox models were used to evaluate the association between the ELN count and N+% and overall survival after adjusted for clinicopathologic features (i.e., race/ethnicity, sex, age, marital status, SEER region, year of diagnosis, tumor grade, tumor site, 8th AJCC T stage, and surgical type). Restricted cubic spline modeling was used to handle possible nonlinear effects of the ELN count as a continuous covariate in the multivariable models. Structural breakpoints, which were considered the threshold of clinical impact, were determined by the Chow test. Results: The median ELN count increased from 9 (interquartile range: 5−15) in 2000 to 16 (11−23) in 2012 ( P<jats:sub>trend</jats:sub> &lt; 0.001), and the N+% increased from 61.1% to 67.2% ( P<jats:sub>trend</jats:sub> &lt; 0.001). An increased ELN count was associated with a nonlinear increase in N+% ( P &lt; 0.001), and the Chow test revealed a threshold ELN count of 8 (OR<jats:sub>adjusted</jats:sub> for ≥ 8 vs. &lt; 8 ELNs, 2.42 [95% CI, 2.19−2.68]). The 8-ELN threshold was confirmed in patients with declared N0 disease: A larger number of ELNs was correlated with a nonlinear increase in overall survival among these patients ( P &lt; 0.001), with the threshold ELN count also being 8 (HR<jats:sub>adjusted</jats:sub>for ≥ 8 vs. &lt; 8 ELNs, 0.79 [95% CI, 0.75−0.87]). Moreover, the 8-ELN threshold remained valid regardless of T stage and year of diagnosis. Conclusions: Lymph node examination has increased markedly over time and was associated with an overall shift toward higher-staged PADC. We recommend 8 ELNs as the cut point for improvement of prognostic accuracy and quality measurement of lymph node examination. </jats:p>

• 出版日期2017-5-20
• 单位中山大学