Wenquan Liang, Kecheng Zhang, Hongqing Xi, Jianxin Cui, Aizhen Cai, Jiyang Li, Yunhe Gao, Xiaosong Wu, Xinxin Wang, Bo Wei, Lin Chen. Chinese PLA General Hospital
BACKGROUND: Tumor deposits (TDs) are defined as satellite tumor nodules without histologic evidence of residual lymph node in peritumoral or regional lymph node areas. TD are markers of poor prognosis in patients with advanced gastric cancer. The accurate staging of gastric cancer is of utmost importance for treatment plan and prognosis. However, the role of perigastric TDs in gastric cancer TNM staging is poorly studied.
METHODS: We established a novel N category strategy which counted tumor deposits as positive lymph nodes in TNM staging and evaluated its prognostic value for stage III gastric cancer. The positive lymph nodes in this novel N were calculated as the numbers of standard positive lymph nodes plus TDs. The database (2011-2014) was retrospectively reviewed for resectable stage III gastric cancer and stratified by presence of TDs. Univariate and multivariate analyses were performed to evaluate the overall survival (OS) for this novel N strategy.
RESULTS: Out of 1987 patients, 285 (14.3%) cases with TDs were identified. TDs were associated with pTNM-stage, N-stage, poor differentiation and vascular invasion. The median survival time of positive TD patients was significantly shorter as compared to negative TD patients(27 months vs. 41 months, P=0.02). A significant positive correlation was observed between the number of TDs and tumor stage, and the number of TDs >3 was a powerful and independent predictor of prognosis. Further, the novel N strategy showed better differentiation ability in survival curves. However, cox regression multivariate analysis showed that both novel N and the standard N categories were independent prognostic factors and the performance of the novel N category did not reveal significant improvement compared to the standard one (c-index 0.611 vs. 0.623, p=0.17).
CONCLUSIONS: TDs are an independent predictive prognostic factor in stage III gastric cancer and may be appropriately considered as a form of positive lymph nodes.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 94773
Program Number: P478
Presentation Session: Poster Session (Non CME)
Presentation Type: Poster