An immunosuppressive scoring system to predict recurrence and assist in decision regarding postoperative adjuvant treatment in gastric cancer.

Inhibition of the immune microenvironment is the main cause of tumor recurrence after surgery in patients with gastric cancer (GC). In this study, immunohistochemistry and multiple immunofluorescence staining were used to evaluate immunosuppressive indicators and immune biomarkers in 825 patients with gastric cancer from three centers. We constructed an immunosuppressive recurrence score (IRS) using LASSO Cox regression based on the expression of six immunosuppressive indicators and found that the IRS and IRS-based nomogram were significantly accurate and reliable in predicting recurrence. Moreover, an elevated IRS was associated with locoregional recurrence and postoperative adjuvant chemotherapy failure. Furthermore, an increase in IRS indicated inhibition of the antitumor effect of CD8 tumor-infiltrating lymphocytes in the invasive margin. Thus, we propose that the IRS can predict the recurrence outcome of patients with GC by distinguishing the immunosuppressive status, which is helpful in the selection of individualized adjuvant treatment plans.