Pretreatment System Inflammation Response Index (SIRI) is a Valuable Marker for Evaluating the Efficacy of Neoadjuvant Therapy in Breast Cancer Patients.

OBJECTIVE

Immune inflammatory response are involved in the development and progression of cancer. However, there are still inconsistent research results on the value of peripheral blood inflammatory indicators for evaluating the efficacy of neoadjuvant therapy (NAT) in breast cancer. The purpose of this study was to investigate the relationship between pretreatment systemic immune inflammatory response index (SII), systemic inflammatory response index (SIRI), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR) and NAT efficacy in breast cancer.

METHODS

A retrospective analysis was performed on 326 patients with breast cancer who underwent NAT at Meizhou People's Hospital from November 2017 to October 2023. Clinicopathological data was collected, including gender, age, body mass index (BMI), hypertension, diabetes mellitus, family history of cancer, TNM stage, and the molecular subtypes of breast cancer. The optimal cutoff values of SII, SIRI, NLR, PLR, and LMR were calculated using receiver operating characteristic (ROC) curve, and the relationship between inflammatory indexes and other clinicopathological features and the efficacy of NAT was analyzed.

RESULTS

In this study, 162 (49.7%) breast cancer patients did not respond to NAT and 164 (50.3%) patients responded to NAT. The levels of SII (=0.002), SIRI (<0.001), and NLR (=0.006) in patients who responded to NAT were significantly higher than those in patients who did not. When the efficacy of NAT was considered as the endpoint of SII, SIRI, and NLR, the critical value of the SII, SIRI, and NLR was 572.53 (under the ROC curve (AUC)=0.598), 0.745 (AUC=0.630), and 2.325 (AUC=0.588), respectively. Logistic regression analysis showed that a high SIRI level (≥0.745/<0.745, OR: 2.447, 95% CI: 1.375-4.357, =0.002) was an independent factor associated with the efficacy of NAT in breast cancer patients.

CONCLUSION

High SIRI levels (≥0.745) may be an independent factor associated with the efficacy of NAT in patients with breast cancer.