The Systemic Immune-Inflammation Index as an Independent Predictor of Survival in Patients with Locally Advanced Esophageal Squamous Cell Carcinoma Undergoing Neoadjuvant Radiotherapy.

ABSTRACT

Purpose: Patients with locally advanced esophageal squamous cell carcinoma (ESCC) scheduled for neoadjuvant radiotherapy still have a poor prognosis. This study was to explore the prognostic value of the pretreatment systemic immune-inflammation index (SII) in patients with locally advanced ESCC after neoadjuvant radiotherapy (NRT). Materials and Methods: Eighty-two consecutive patients with ESCC scheduled for neoadjuvant radiotherapy between 2011 and 2017 were enrolled in this study. SII values (SII = platelet × neutrophil/lymphocyte), prognostic nutritional index values (PNI = albumin concentration (g/L) + 5 × total lymphocyte count (109/L)), platelet-lymphocyte ratio (PLR), and neutrophil-lymphocyte ratio (NLR) were retrospectively collected and calculated before treatment. The Cut-off Finder application was applied to find out the cut-off points of the SII, NLR, PNI and PLR. A regression model was used to examine prognostic factors for overall survival (OS) rates. Results: The median follow-up was 44 months (3 to 83). Sixty patients (73.17%) underwent surgery as scheduled. This study found that factors improving OS were a lower SII (≤916.6 × 109/L) (P=0.040) and neoadjuvant chemoradiotherapy (NCRT) (P=0.034). The patients with a lower SII and NCRT had a better OS (P< 0.001). Moreover, additionally, a higher SII was associated with a lower resectability rate (P=0.035). Conclusion: The SII can predict resectability in ESCC patients following neoadjuvant radiotherapy. Both the SII and neoadjuvant chemoradiotherapy appear to influence OS.