A Multi-marker model based on serum IL-10 predicts response to conversion immunochemotherapy in gastric cancer patients: a retrospective cohort study.

BACKGROUND: Conversion immunochemotherapy may enable curative surgery in patients with initially unresectable locally advanced gastric cancer, but its response rate remains low. Little evidence has shown how to easily predict therapeutic efficacy from hematological biomarkers, apart from tissue biomarkers. This study aimed to identify predictive factors for treatment response from hematological biomarkers and propose strategies for non-responsive patients. METHODS: Clinical and laboratory data from 153 PD-L1 negative and microsatellite stable advanced gastric cancer patients treated with conversion immunochemotherapy followed by radical gastrectomy were retrospectively analyzed. Correlations between key indicators and treatment outcomes were assessed, and a nomogram was developed to predict tumor regression grade (TRG). RESULTS: TRG was strongly associated with the prognosis of advanced gastric cancer treated with conversion immunochemotherapy. Factors significantly related to TRG included hypertension, pre-treatment serum albumin levels, tumor size, post-treatment serum IL-10, IFN-γ, TNF-α, and changes in tumor-associated carbohydrate antigens before and after treatment. Hypertension, pre-treatment serum albumin levels, post-treatment IL-10 levels, and restoration in tumor-associated carbohydrate antigens were identified as independent predictors of TRG. CONCLUSION: Dynamic monitoring of serum albumin, IL-10, and tumor-associated carbohydrate antigens can help assess treatment response and identify patients sensitive to conversion immunochemotherapy. For non-responsive patients, strategies such as the associations observed require validation in prospective interventional trials before specific interventions can be recommended.