Abstract
BACKGROUND: Locally advanced gastric cancer presents significant challenges in treatment, often limiting the effectiveness of surgical interventions. Chemotherapy, especially the SOX regimen (combining oxaliplatin and tegafur/gimeracil/oteracil), has been explored as a potential alternative in the management of advanced gastric cancer. While studies on SOX have been conducted in other regions, its impact on immune function and tumor markers remains inadequately evaluated, particularly in China. OBJECTIVE: This study aimed to assess the toxicological profile, immune function modulation, and tumor marker reduction of the SOX regimen in patients with advanced gastric cancer. METHODS: A retrospective analysis was conducted on 100 patients diagnosed with advanced gastric cancer, excluding eight ineligible cases. Based on clinical records, patients were grouped into either the oxaliplatin monotherapy group (reference group) or the SOX regimen group (observation group), with 50 patients in each group. The primary endpoint was clinical effectiveness, while secondary endpoints included immune function, tumor marker levels, and chemotherapy-related toxicity. RESULTS: The SOX regimen demonstrated significantly higher disease control and objective remission rates compared to oxaliplatin monotherapy (P<0.05). In the SOX group, immune function was enhanced, with increased levels of immunoglobulins (IgA, IgG, IgM) and lymphocyte subsets (CD3+, CD4+, NK cells), and a decrease in CD8+ levels (P<0.05). Additionally, tumor markers such as CA125, CEA, MRP14, SDF-1, FSP-1, and CXCR4 showed a significant reduction (P<0.05). The SOX regimen also exhibited a more favorable safety profile, with lower incidences of chemotherapy-related nausea, vomiting, and leukopenia (P<0.05). CONCLUSION: The SOX regimen is an effective and promising treatment option for advanced gastric cancer, offering significant improvements in clinical outcomes, immune function, and tumor marker reduction, with fewer chemotherapy-related toxicities. This study provides valuable insights into the application of the SOX regimen in Chinese patients with advanced gastric cancer.