Role of pretreatment absolute lymphocyte count in survival outcomes for esophageal cancer treated with neoadjuvant chemoradiotherapy and pembrolizumab: An analysis from a prospective cohort.

Abstract

338 Background: To analyze the relationship between pre-treatment inflammatory biomarkers (IBs) and survival outcomes for ESCC treated with neo-CRT and pembrolizumab. Methods: Clinical variables and IBs [absolute monocyte count (AMC), absolute lymphocyte count (ALC), platelet count (PLT), neutrophil lymphocyte ratio (NLR), Platelet lymphocyte ratio (PLR), Lymphocyte monocyte ratio (LMR), Pan-Immune Inflammation value (PIV), Systemic immunoinflammatory index (SII), Systemic Immunoreactivity Index (SIRI) and prognostic nutritional index (PNI)] were collected from two prospective trials. Univariate and multivariate analysis was performed. Results: A total of 51 patients were included. Of them, 35 patients achieved pathologic complete response after neo-CRT and pembrolizumab (pCR: 68.6%). With a median follow-up of 20 months, the two-year PFS and OS of the cohort was 64% and 91%, respectively. Multivariate logistic regression analysis indicated that ALC (OR 4.4, p=0.051) and PLT (OR 6.7, p=0.023) were two independent predictors for achieving pCR among ESCC treated with neo-CRT and pembrolizumab. Multivariate Cox regression analysis showed that ALC (HR 0.27, p=0.028) and SIRI (HR 3.13, p=0.048) were two independent predictors for PFS of this patient population. K-M analysis demonstrated that the PFS of ESCC with high base line ALC was significantly better than those with low ALC (2-year PFS: 77% vs. 47%, p=0.027), but not for overall survival (2-year OS: 96% vs. 87%, p=0.46). Conclusions: Our data demonstrates that pre-treatment ALC is an independent predictor for archiving pCR and favorable outcomes of ESCC treated with neo-CRT and pembrolizumab. Clinical trial information: NCT04435197 ; NCT04435197 .[Table: see text]