1321P Advanced lung cancer inflammation index (ALI score) as a biomarker of immunotherapy efficacy in patients with advanced non-small cell lung cancer: A nationwide analysis in Greece

To date, there is no optimal surrogate for efficacy of immune checkpoint inhibitors in advanced non-small-cell lung cancer (NSCLC). Advanced Lung Cancer Inflammation Index (ALI score: body mass index X serum albumine/blood neutrophil-to-lymphocyte ratio) reflects the systemic inflammation of the host and is easily reproducible in routine clinical practice. In a Nation-wide study, we retrospectively analyzed patients with stage III or IV NSCLC who received PD1/PD-L1 inhibitors alone or in combination with chemotherapy in any line of treatment in 25 cancer centers in Greece. For every patient we recorded demographic, somatometric and clinicopathological characteristics, as well as clinical outcomes of immunotherapy. ALI score was evaluated as a marker of efficacy through appropriate statistical tests. Seven hundred and three (703) patients were included in final analysis, of whom 71.7% were men, 67.2% had tumors of adenocarcinoma histology, 88.4% had stage IV disease at diagnosis, 39.4% received immunotherapy as 1st-line treatment and 74.9% as monotherapy. Median age at diagnosis was 68 years, median BMI was 25.1 kg/m2, median albumin level was 3.9 g/dl and 35.4% of the patients had PD-L1 expression of more than 50%. Using the bibliographic cut-off value of 18 for ALI, patients with ALI>18 had significantly longer PFS (12 vs 5.6 months, p<0.001) and OS (23.1 vs 12.0 months, p<0.001). In multivariate analysis, patients with ALI>18 had a 41% lower probability of disease progression (HR=0.594, 95%CI 0.487-0.724, p<0.001) and 45% lower probability of death (HR=0.549, 95%CI 0.445-0.678, p<0.001) as compared to those with ALI<18, independent of Performance Status, stage at diagnosis, line of treatment and level of PD-L1 expression. There was no statistically significant correlation of ALI with objective response rates to immunotherapy (PD vs CR or PR or SD, p=0.623). ALI score correlates with clinical benefit from immunotherapy in advanced NSCLC independent from significant co-variables and may assist decision-making in clinical practice. Further validation of its value as a predictive marker of immunotherapy efficacy is ongoing.