The Prognostic Value of Pretreatment A Composite Biomarker of Natrium and Myeloid to Lymphoid lineage ratio in Patients With Advanced or Metastatic Gastric Cancer Treated With Immunotherapy

Abstract

Abstract Background Immunotherapy is effective for only some patients with advanced gastric cancer (AGC). Screening and determining patients who are suitable for immunotherapy is a difficult task in the field of tumor immunology. Patients with tumors often have sodium ion imbalance and changes in tumor microenvironment. The correlation between serum sodium level and tumor prognosis has been incredibly concerning. Targeting the tumor immune microenvironment to enhance the anti-tumor ability of immune cells, and thus improving the effect of therapeutic treatment of tumors is a research hotspot in recent years. However, the correlation between serum sodium level and immunotherapy has not been reported. Therefore, we collected the clinical records and follow-up data of 268 patients with AGC who received immunotherapy, and deeply analyzed whether a composite biomarker of natrium (Na) and myeloid to lymphoid lineage ratio (M:L) is suitable as a prognostic indicator for screening patients for immunotherapy. Methods The median of 3.58 was taken as the optimal cut-off value. The optimal cut-off value was determined according to M:L, and the patients were then divided based on M:L into two groups: Low-level group (< 3.58) and High-level group (≥ 3.58). The optimal cut-off value of serum Na was 135mmol/L, which was the lowest limit of the normal range of blood biochemical results in the Cancer Center Department of PLA General Hospital. According to the optimal cut-off value of serum Na and M:L, patients were divided into two groups: The good Na/M:L group (145mmol/L > Na ≥ 135mmol/L and M:L < 3.58) and intermediate/poor Na/M:L group (Na < 135mmol/L and M:L ≥ 3.58 ). The differences in progression-free survival (PFS) and overall survival (OS) in the two Na/M:L groups were compared by survival analysis and log-rank test. COX was used for univariate and multivariate analysis to determine the presence of correlation between Na/M:L grouping and OS and PFS. Results Patients in the good Na/M:L group were associated with longer PFS and OS compared to the intermediate/poor Na/M:L group (6.3 vs 3.6 months, 15.8 vs 9.5 months). The intermediate/poor Na/M:L group was independently associated with a 1.9-fold greater risk of disease progression (HR=1.584; 95% CI, 1.206-2.080; P=0.001) and more than 1.4-fold greater risk of death (HR=1.466; 95% CI, 1.069-2.011; P=0.018), compared to the good group. Conclusion This study confirms for the first time that the composite biomarker of Na and M:L is an independent factor affecting survival of AGC patients receiving immunotherapy. Thus, patients in the good Na/M:L group could be identified to benefit from immunotherapy.