Abstract:

Objective To investigate the prognostic value of TCBI in middle-aged and elderly patients with thoracic esophageal squamous cell carcinoma (ESCC) who received radiotherapy. Methods The clinical data of 191 patients with thoracic ESCC who underwent radiotherapy in the department of Radiation Oncology of the First Affiliated Hospital of Soochow University from January 2010 to December 2015 were retrospectively analyzed. According to the TCBI value on admission [TCBI=serum triglyceride (mg/dl) × total cholesterol (mg/dl) × body weight (kg)/1 000], patients were divided into TCBI low-value group (n=79) and TCBI high-value group (n=112). The relationships between TCBI and clinicopathological characteristics of patients were analyzed. The Kaplan-Meier method was used to calculate the overall survival (OS). The log-rank test was adopted to compare the differences in survival between different groups. The Cox proportional hazard model was used to analyze the factors affecting the prognosis of middle-aged and elderly patients with thoracic ESCC. The receiver operating characteristics (ROC) curve was applied to verify the accuracy of TCBI for survival prediction. Results The mean pre-radiotherapy TCBI was 1 082±945 in all patients. The cutoff value of the TCBI was 749. The patients with TCBI<749 served as the TCBI low-value group , and patients with TCBI≥749 served as the TCBI high-value group. TCBI was associated with treatment (χ ²=4.235, P=0.040) and geriatric nutritional risk index (GNRI, χ ²=8.795, P=0.003). Univariate analysis suggested that male (HR=2.220, 95%CI: 1.223-4.030, P=0.009), stage N_1-3 (HR=1.453, 95%CI: 1.023-2.065, P=0.037), GNRI<98 (HR=1.949, 95%CI: 1.168-3.255, P=0.011) and TCBI<749 (HR=1.846, 95% CI: 1.298-2.627, P=0.001) were risk factors affecting OS in middle-aged and elderly patients with thoracic ESCC. Besides, postoperative adjuvant radiotherapy (HR=0.641, 95%CI: 0.449-0.915, P=0.014) was a protective factor. Furthermore, multivariate analysis showed that male (HR=2.147, 95%CI: 1.173-3.929, P=0.013) and TCBI<749 (HR=1.664, 95%CI: 1.166-2.376, P=0.005) were independent risk factors for OS. Besides, postoperative adjuvant radiotherapy (HR=0.630, 95%CI: 0.439-0.903, P=0.012) was an independent protective factor. The area under the curve calculated by the ROC curve was 0.619, the sensitivity was 0.742, and the specificity was 0.496 (P=0.007), confirming the role of TCBI in the prognostic evaluation. Survival analysis showed that the median OS of patients in the TCBI high-value group was 42 months, and the 1-year and 3-year survival rates were 86.6% and 52.7%, significantly higher than those in the TCBI low-value group (20 months, 68.4% and 29.1% respectively; χ ²=12.286, P<0.001). Subgroup analysis showed that among patients with radical radiotherapy, 3-year survival rate in patients with lower TCBI (n=37) was lower than that in patients with higher values (n=36) (21.6% vs. 44.4%, χ ²=8.505, P=0.004). Conclusion TCBI is a predictor of OS for middle-aged and elderly patients with thoracic ESCC who received radiotherapy. The lower the TCBI, the poorer the survival prognosis.

Key words: Esophageal neoplasms, Malnutrition, Prognosis