Systemic Immune-inflammation Index is the Best Prognostic Factor in Patients with Advanced Stage Adenocarcinoma of the Lung Treated with Pemetrexed.

OBJECTIVE

To evaluate the prognostic role of systemic immune-inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) in patients who received platin-pemetrexed combination therapy and/or maintenance pemetrexed therapy.

STUDY DESIGN

Observational study.

PLACE AND DURATION OF STUDY

Department of Medical Oncology, HSU Dr. Abdurrahman Yurtaslan Oncology, Training and Research Hospital, Turkey, between January 2010 and March 2020.

METHODOLOGY

Data of patients with metastatic adenocarcinoma of lung, who underwent platin-pemetrexed combination therapy and/or maintenance pemetrexed therapy retrospectively, were evaluated. Patient characteristics and disease parameters were recorded. Moreover, NLR, PLR, and SII were calculated. Survival analysis with the Kaplan-Meier and Log-rank test was performed. Cox regression analysis was used to determine independent prognostic factors of overall survivall (OS) and progression-free survival (PFS).

RESULTS

In the univariate analyses, NLR-low group and SII-low group had significantly longer PFS compared to NLR-high and SII-high groups (10 months vs. 8 months, p=0.018, and 13 months vs. 8 months, p<0.001, respectively). The significant differences were seen between SII-low and SII-high groups for OS (24 months vs. 13 months, p=0.001). In multivariate analyses, response to treatment and low-SII were independent prognostic factors for PFS (HR: 0.25, p<0.001, and HR: 0.47, p=0.002, respectively) and OS (HR: 2.09, p=0.001, and HR: 2.05, p=0.001, respectively).   Conclusion: SII is the most powerful of the three studied inflammatory indices, which could independently predict overall and progression-free survival. Key Words: Systemic immune-inflammation index, Neutrophil-to-lymphocyte ratio, Platelet-to-lymphocyte ratio, Adenocarcinoma, Lung cancer, Pemetrexed.