RESUMEN
This study aimed to conduct a survival analysis of thoracic esophageal squamous cell carcinoma (ESCC) patients treated with radical chemoradiotherapy and identify prognostic variables from among the hematological and radiation parameters. Cases of patients with ESCC receiving definitive chemoradiotherapy at Jiangsu Cancer Hospital between January 2018 and September 2020 were screened. A Cox proportional hazards model was used to assess the effect of hematological and radiation parameters on the overall survival (OS). The neutrophil-to-lymphocyte ratio (NLR) was calculated by dividing the absolute neutrophil count (ANC) by the absolute lymphocyte count (ALC) in the week prior to radical chemoradiotherapy. Variables associated with radiation were gathered based on dose-volume histograms (DVH). X-tile software was used to determine the optimal cutoff values for pretreatment NLR and posttreatment ALC nadir. Associations between lymphopenia and dose-volume parameters were analyzed using multivariate logistic regression. The study included 104 ESCC patients. The median follow-up of surviving patients was 45.0 months (interquartile range: 40.2-52.2), with 1- and 3-year OS rates of 88.0% and 62.7%, respectively. Multivariate Cox regression analysis demonstrated a significant survival benefit in patients with low baseline NLR (≤ 2.2), high ALC nadir (> 0.24*109/L), and desirable radiation parameters for the heart and thoracic vertebrae. Increased dose-volume parameters of the heart, lungs, and thoracic vertebrae were correlated with a high probability of radiation-induced lymphopenia (RIL) risk (P < 0.05). Baseline NLR and RIL are significantly related to survival outcomes in ESCC patients. Optimization of radiation parameters of cardiopulmonary and thoracic vertebrae can be effective in the prevention of RIL.
