Preliminary study on SIRI dynamic changes for the efficacy prediction and prognosis evaluation of advanced cancer patients treated with immunotherapy

To investigate the values of systemic inflammatory response index (SIRI) and its dynamic changes in predicting the efficacy and evaluating the prognosis of immunotherapy for advanced cancers. A retrospective analysis was conducted on the clinical data of 245 patients with locally advanced and advanced cancers who received immune checkpoint inhibitors (ICI) treatment at the 940 Hospital of the Joint Logistics Support Force from June 2020 to June 2023.The χ2-test was used to compare the clinical pathological characteristics of patients in the disease control group and the no-control group, and Kruskal-Wallis test was used to compare the differences in SIRI pre-treatment, disease remission, and disease progression. The correlation between SIRI and progression free survival (PFS) of patients was analyzed using Kaplan-Meier survival curve and Log-rank test; and factors affecting PFS in cancer patients receiving ICIs treatment were analyzed through univariate and multivariate COX regression analysis. There was a significant difference in the number of treatment lines between the disease control group and no-control group (P = 0.042), but no significant differences were observed in gender, age, tumor differentiation, number of metastatic organs and treatment plan between the two groups (P > 0.05). Compared with pre-treatment, the SIRI decreased during disease remission and increased again during disease progressed. Kaplan- Meier survival curves indicated that patients with high SIRI had shorter PFS than those with low SIRI (P = 0.019, < 0.001, 0.012). Univariate and multivariate COX regression analysis revealed that pre-treatment high SIRI (HR = 2.804,95%CI 1.150 ~ 6.838, P = 0.023) and disease remission high SIRI (HR = 2.469,95%CI 1.513 ~ 4.029, P<0.001) were independent risk factors for PFS in cancer patients undergoing immunotherapy. The inflammatory index SIRI can be a dynamic biomarker for evaluating the efficacy and prognosis of advanced cancer patients receiving ICI treatment.