The Systemic Oxidative Stress Score (SOSS) , a comprehensive score reflecting the oxidative stress conditions in the microenvironment, can independently and effectively predict tumor burden and long-term prognosis in GC patients. Nomograms based on SOSS provide a potential and promising model for risk stratification and guiding the implementation of treatment decisions.

We retrospectively analyzed the clinical data of gastric cancer patients who underwent radical gastrectomy in three hospitals from January 2009 to June 2020. The data from one hospital were randomly divided into a training cohort and an internal validation cohort in a 7:3 ratio, while the data from the other two centers were used as an external validation cohort. In the training cohort, COX proportional risk models were employed to identify key indicators of SOSS and independent prognostic factors influencing patients' OS and DFS. Subsequently, based on the results of the multifactor COX analysis, two predictive models for OS and DFS were developed. The predictive efficacy, calibration, and clinical utility of the models were evaluated using ROC curves, calibration curves, and decision curves in the internal and external validation cohorts, respectively. Both models demonstrated good discriminative ability between postoperative survival and recurrence risk, outperforming TNM staging in terms of predictive accuracy.

Inclusion Criteria:

1) gastroscopic histopathological diagnosis of gastric adenocarcinoma; 2) radical gastrectomy for GC; 3) preoperative examination of oxidative indicators including Fbg, CHOL, ALB, TBIL, DBIL, and CR within seven days before surgery; and 4) the tumor did not invade neighboring organs or had no distant metastasis.

Exclusion Criteria:

1) gastroscopic histopathological diagnosis of non-adenocarcinoma, 2) gastric stump cancer, 3) neoadjuvant chemotherapy, 4) other malignant diseases besides GC, 5) incomplete medical records, and 6) patients with GC lost to follow-up.

This study is a multicenter, retrospective cohort investigation involving GC patients who underwent radical gastrectomy at the Fujian Medical University Union Hospital (FMUUH), the First Affiliated Hospital of Gannan Medical University (FAHGMU) and Quzhou Affiliated Hospital of Wenzhou Medical University (QAHWMU) between January 2009 and June 2020.