Abstract 461P
Background
Gastric cancer poses a significant societal burden worldwide, prompting the need for refined surgical strategies to improve patient outcomes. Given the differing disease conditions between patients undergoing radical subtotal gastrectomy (RSG) and radical total gastrectomy (RTG), as well as the potential for understaging and postoperative recurrence due to inadequate lymph node dissection, it is crucial to establish the standard number of retrieved lymph nodes (rLNs) and negative lymph nodes (nLNs) during surgery for each procedure.
Methods
Patients who underwent either RSG or RTG at Fudan University Shanghai Cancer Center (FUSCC) between 2000 and 2022 were retrospectively included. We utilized restricted cubic spline (RCS) analysis to determine the ideal threshold for rLNs and nLNs. Survival analysis was conducted using Kaplan-Meier (KM) curves, log-rank tests and forest plots. Propensity score matching (PSM) was utilized to balance parameters between the two groups.
Results
For patients with N0-N3a stage undergoing RSG, retrieving ≥24 lymph nodes intraoperatively was associated with better prognosis (pre-PSM: P < 0.001, post-PSM: P = 0.019); whereas for N3b stage, at least 32 rLNs were required (pre-PSM: P = 0.006, post-PSM: P = 0.023). Similarly, for patients with N0-N3a stage undergoing RTG, retrieving ≥27 lymph nodes intraoperatively was associated with better prognosis (pre-PSM: P <0.001, post-PSM: P = 0.047); whereas for N3b stage, at least 34 rLNs were required (pre-PSM: P < 0.001, post-PSM: P = 0.003). Additionally, for patients undergoing RSG, having ≥21 nLNs (pre-PSM: P < 0.001, post-PSM: P = 0.013), and for those undergoing RTG, having ≥22 nLNs (pre-PSM: P < 0.001, post-PSM: P < 0.001), were also associated with better prognosis.
Conclusions
For patients receiving RSG, rLNs should reach 24 when lymph nodes are limited, and 32 when lymph node metastasis is more extensive, with an optimal number of nLNs ideally reaching 21. Similarly, for patients receiving RTG, rLNs should reach 27 when lymph nodes are limited, 34 when lymph node metastasis is more extensive, and an optimal number of nLNs ideally reaching 22.
Legal entity responsible for the study
The authors.
Funding
National Natural Science Foundation of China.
Disclosure
All authors have declared no conflicts of interest.