1
Department of Oncology, People's Hospital of Tinghu District, Yancheng City, Yancheng 224000, Jiangsu, China; 2
Department of Rheu?
matology and Immunology, General Hospital of Eastern Theater Command, Nanjing 210002, Jiangsu, China
Abstract：Objective To investigate the predictive value of prognostic nutritional index (PNI) and cytotoxic T lymphocyte associated
antigen 4 (CTLA⁃4) expression level in peripheral blood for postoperative recurrence of esophageal squamous cell carcinoma (ESCC)
patients. Methods A total of 133 ESCC patients who underwent curative resection in People's Hospital of Tinghu District, Yancheng City
and General Hospital of Eastern Theater Command from April 2014 to June 2018 were included, and the clinic pathological and follow⁃up
data of all patients were retrospectively collected. Receiver operating characteristics (ROC) curve was used to determine the optimal cut⁃off
point and predictive value of preoperative PNI and CTLA⁃4 expression level in peripheral blood for postoperative recurrence in ESCC
patients. Kaplan⁃Meier curve was plotted to evaluate the impact of PNI and CTLA⁃4 expression level in peripheral blood on the
recurrence⁃free survival (RFS) of ESCC patients. In addition, Cox multivariate regression analysis was performed to determine the
independent predictors of postoperative recurrence and metastasis in ESCC patients. Results ROC curve indicated that the cut⁃off values
of PNI and CTLA⁃4 expression in peripheral blood for predicting recurrence of ESCC patients were 48.2 and 0.410 ng/ml, respectively.
The AUC values for PNI and CTLA⁃4 expression in peripheral blood were 0.666 (95%CI= 0.572-0.759) and 0.606 (95%CI=0.507-0.704),
respectively. Based on the optimal cut⁃off point, high CTLA⁃4 expression in peripheral blood was significantly associated with histological
grade (χ２ = 10.231, P=0.001) and T stage (χ２ = 5.198, P=0.023). Kaplan⁃Meier curve showed that ESCC patients with high CTLA⁃4
expression had a poorer RFS than those with low CTLA⁃4 expression (5⁃year RFS rate, 41.7% vs 61.2%), with a statistically significant
difference (χ２= 3.919, P=0.047). On the other hand, the 5⁃year RFS of ESCC patients with preoperative PNI <48.2 was significantly worse
than that of those with PNI ≥48.2 (39.6% vs 61.3%, χ２ = 6.362, P=0.016). Multivariate Cox regression analysis further confirmed the
independent prognostic significance of PNI (HR=3.043, 95%CI=1.290-7.179, P=0.011) and CTLA⁃4 expression in peripheral blood (HR=2.250, 95%CI=1.286-3.938, P=0.004) in ESCC patients. In addition, ROC curve showed that the AUC value of PNI combined with
CTLA⁃4 expression in peripheral blood for predicting recurrence in ESCC patients was 0.694 (95%CI= 0.604-0.7849), which was better
than that of either PNI or CTLA⁃4 expression alone. Conclusion Combination of PNI and the expression level of CTLA⁃4 in peripheral
blood further improved predictive performance of recurrence in ESCC patients, and it might be a sensitive indicator for prognostic assessment
of ESCC patients.
