Abstract 4462: Association of lymphocyte-to-monocyte ratio and systemic inflammation index with survival in advanced gastric cancer patients treated with immune checkpoint inhibitor
Authors: Chen Yang , Zhang Cheng , Qi Changsong , Peng Zhi , Gong Jifang , Zhang Xiaotian , Li Jian , Shen Lin 
Published: September 2020

Abstract
Background Optimal prognostic biomarkers for patients with gastric cancer who received immune checkpoint inhibitor (ICI) are lacking. Inflammatory markers including lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), and systemic inflammation index (SII) are easily available. Here, we evaluated the potential association between LMR, PLR, and SII with clinical outcomes in gastric cancer patients undergoing ICI therapy.
Methods We examined LMR, PLR, SII at baseline and 6 (±2) weeks later in 139 patients between August 2015 and April 2019 at Peking University Cancer Hospital (Beijing, China). Landmark analysis at 6 weeks was conducted to explore the prognostic value of LMR, PLR, and SII on progress-free survival (PFS), and overall survival (OS). Cox regression models allowed for adjustment of potential confounders including age, sex, KPS, tumor location, Lauren classification, line of therapy, and type of anti-PD-1/PD-L1 therapy.
Results Among 139 patients, 103 (74.1%) were male, and median age was 60 years. Median duration on therapy was 6 cycles. We observed that both LMR at baseline and week-6, SII at baseline and week-6 were independent prognostic factors. Whereas, the association between PLR at baseline or week-6 with mortality appeared to be pronounced. Patients with a higher LMR(≥ 3) at baseline or week-6 had superior PFS [baseline: hazard ratios (HR) 0.55, 95% confidence interval (CI): 0.34-0.89; week-6: HR 0.33, 95%CI 0.19-0.55] and OS (baseline: HR 0.30, 95% CI: 0.15-0.57; week-6: HR 0.29, 95% CI: 0.15-0.58) than patients with a lower LMR(&lt; 3). Furthermore, for patients with both LMR ≥ 3 at baseline and LMR ≥ 3 at week-6 was estimated to have much better PFS (HR 0.36, 95% CI: 0.19-0.67) and OS (HR 0.19, 95%CI: 0.08-0.48) than patients with both LMR &lt; 3 at baseline and LMR &lt; 3 at week-6 (mPFS: 7.8m vs. 4.3m, P &lt; 0.0001; mOS: 19.0 vs. 9.8m, P = 0.0058). In addition, patients with a higher SII (≥ 694.5) at baseline or week-6 had inferior PFS (baseline: HR 1.69, 95% CI: 1.07-2.66; week-6: HR 2.99, 95%CI: 1.76-5.08) and OS (baseline: HR 2.05, 95%CI: 1.16-3.65; week-6: HR 3.90, 95%CI: 1.92-7.94) than patients with a lower SII (&lt; 694.5). Furthermore, patients with both SII ≥ 694.5 at baseline and SII ≥ 694.5 at week-6 was estimated to have much worse PFS (HR 4.05, 95% CI: 2.10-7.78) and OS (HR 6.51, 95%CI: 2.48-17.1) than patients with both SII &lt; 694.5 at baseline and SII &lt; 694.5 at week-6 (mPFS: 2.4m vs. 8.5m, P = 0.0004; mOS: 6.7m vs. 19.0m, P &lt; 0.0001).
Conlusions Baseline and early changes in LMR and SII were strongly associated with survival in gastric cancer patients who received ICI therapy, and may serve to identify patients most likely to benefit from ICI.
Citation Format: Yang Chen, Cheng Zhang, Changsong Qi, Zhi Peng, Jifang Gong, Xiaotian Zhang, Jian Li, Lin Shen. Association of lymphocyte-to-monocyte ratio and systemic inflammation index with survival in advanced gastric cancer patients treated with immune checkpoint inhibitor [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4462.