The Prognostic Impact of Preoperative Serum Apolipoprotein A-I in Patients with Esophageal Basaloid Squamous Cell Carcinoma

BACKGROUND: Esophageal basaloid squamous cell carcinoma (EBSCC) is a rare malignancy. Serum apolipoprotein A-I (APO A-I) has proved to be a potentially useful prognostic indicator in various cancers. However, no studies have analyzed the prognostic significance of serum APO A-I in patients with EBSCC. The aim of this study was to investigate the prognostic impact of preoperative serum APO A-I in patients with EBSCC. METHODS: Between 2007 and 2018, a retrospective study of 4050 patients with resectable esophageal squamous cell carcinoma (ESCC) including the levels of preoperative serum lipids was conducted and evaluated. The best cut-off values of the preoperative serum lipids were evaluated by receiver operating characteristic (ROC) curves. Kaplan–Meier analyses and Cox regression analyses were analyzed the overall survival (OS) and recurrence-free survival (RFS). A prediction model of nomogram was developed to predict individual OS and RFS in EBSCC. RESULTS: There were 53 patients enrolled in the study, which accounted for 1.31% (53/4050) of all primary ESCC. The best cut-off point was 1.305 g/L for serum APO A-I according to the ROC curve. Patients with lower levels of serum preoperative APO A-I were associated with worse RFS (16.1% vs 54.5%, P = 0.006) and OS (29.0% vs 63.6%, P = 0.010). The results indicated that serum APO A-I serves as an independent predictor in patients with EBSCC regarding OS [hazard ratio (HR): 0.352; 95% confidence interval (CI): 0.154–0.808; P = 0.014] and RFS (HR: 0.397; 95% CI: 0.185–0.850; P = 0.017). CONCLUSION: Preoperative serum APO A-I is an independent predictor regarding OS and RFS in EBSCC. As far as we know, this is the first study in EBSCC to explore the serum APO A-I in patients with EBSCC.