Effects of systemic immune-inflammation index on long-term survival in esophageal cancer patients treated with radiotherapy / 中华放射医学与防护杂志

ABSTRACT

Objective:To investigate the effects of the systemic immune-inflammation index (SII)on the long-term survival in esophageal cancer patients treated with radiotherapy.Methods:Aretrospective review was conducted for the clinical data of 303 patients with esophageal squamous cell carcinoma(ESCC)who received radical radiotherapy in the Fourth Hospital of Hebei Medical University from 2011 to 2017. These patients were divided into a high-SII group and a low-SII group according to their SII before radiotherapy. The correlation between SII and survival was determined using the Kaplan-Meier method and Cox regression model. Propensity score matching (PSM) was applied to reduce bias from measured confounding.Results:The SII of patients before radiotherapy was correlated significantly with T stage ( χ2=8.015, P=0.018) and TNM stage ( χ2=8.619, P=0.013). The 1-, 3-, 5-year overall survival (OS) rates in the high-SII group were 64.9%, 27.1%, and 19.4%, respectively. They were significantly lower than those in the low-SII group, which were 84.9%, 43.9%, and 30.5%, respectively (χ 2=13.443, P<0.001). The 1-, 3-, 5-year progression-free survival (PFS) rates in the high-SII group were 46.4%, 20.3%, and 13.3%, respectively. They were significantly lower than those in the low-SII group, which were 67.8%, 34.8%, and 26.5%, respectively (χ 2=12.383, P<0.001). The multivariate analysis indicated that the independent factors influencing the OS and PFS included T stage, lymph node metastasis, chemotherapy, and SII.After PSM was applied, the OS and PFS in the high-SII group were still lower than those in the low-SII group(χ 2OS=4.264, P=0.039; χ 2PFS=5.376, P=0.020), and the multivariate analysis showed that SII was a significant predictor for OS and PFS( HROS=1.357, P=0.037; HRPFS=1.393, P=0.022). Conclusions:SII is a significant independent influencing factor of the OS and PFS inESCC patients treated with received radiotherapy. Based on simple and inexpensive standard laboratory measurements, SII can be a promising marker for ESCC patients.