Patients with lymph node-negative gastric cancer, the prognosis of patients who underwent neoadjuvant therapy was poor than that of those who had upfront surgery.

We retrospectively analyzed the clinicopathological data of patients who underwent curative surgery for gastric cancer and were pathologically confirmed to have node-negative metastases between January 2010 and June 2021 at 8 institutions in China. Data from the Surveillance, Epidemiology, and End Results (SEER) database (2004-2020) were used as the validation cohort. The patients were divided into two groups based on whether they received neoadjuvant therapy before surgery: the upfront surgery (UFS) group and the neoadjuvant therapy followed by surgery (NATS) group. A 1:1 propensity score matching analysis was employed to reduce the potential selection bias between the two groups.

Inclusion Criteria:

(1) preoperative clinical staging of cT2-4NxM0; (2) primary gastric adenocarcinoma confirmed via pathology; (3) no distant metastasis to the liver, lungs, or abdominal cavity as confirmed through preoperative chest X-ray or chest CT, abdominal ultrasound, and abdominal CT; (4) underwent radical gastrectomy (R0) and D2 lymphadenectomy; (5) postoperative pathology confirmed no lymph node metastasis (i.e., lymph node-negative); and (6) follow-up for at least 3 years.

Exclusion Criteria:

(1) considered early-stage gastric cancer before surgery; (2) distant metastasis detected preoperatively or intraoperatively; (3) failure to achieve R0 resection and D2 lymphadenectomy during surgery; (4) concurrent diagnosis of other malignancies; (5) remnant gastric cancer; (6) death within 30 days postoperatively; and (7) incomplete baseline data or follow-up records.

We retrospectively analyzed the clinicopathological data of patients who underwent curative surgery for gastric cancer and were pathologically confirmed to have node-negative metastases between January 2010 and June 2021 at 8 institutions in China. Data from the Surveillance, Epidemiology, and End Results (SEER) database (2004-2020) were used as the validation cohort. The patients were divided into two groups based on whether they received neoadjuvant therapy before surgery: the upfront surgery (UFS) group and the neoadjuvant therapy followed by surgery (NATS) group. A 1:1 propensity score matching analysis was employed to reduce the potential selection bias between the two groups.