CD155/TIGIT overexpression has been detected in various human malignancies; however, its expression status in primary small cell carcinoma of the esophagus (PSCCE) and its prognostic significance remain unclear. In this study, we aimed to explore the expression and prognostic value of CD155 and TIGIT in PSCCE. We detected CD155 and TIGIT expression in 114 cases of PSCCE using immunohistochemistry (IHC) and evaluated their relationship with the clinicopathological characteristics and survival of the patients. Survival analyses were performed using the Kaplan-Meier method and Cox proportional hazards model. Nomogram performance was assessed via the concordance index (C-index) and calibration plots. Decision curve analysis (DCA) was performed to evaluate the net benefit of the nomogram. We found that CD155 and TIGIT were overexpressed in PSCCE tissues, CD155 expression correlated positively with TIGIT (p < 0.001) and was significantly associated with tumor size, T stage, distant metastasis, TNM stage, and Ki-67 score. TIGIT expression was also significantly associated with T stage, distant metastasis, and TNM stage. Patients with high CD155 and TIGIT expression had a significantly shorter overall survival (OS) and progression-free survival (PFS), while the multivariate model showed that CD155 expression and the therapeutic strategy are independent prognostic factors for PSCCE. In the validation step, OS was shown to be well-calibrated (C-index = 0.724), and a satisfactory clinical utility was proven by DCA. In conclusion, our findings revealed that CD155 and TIGIT are highly expressed in patients with PSCCE and are associated with shorter OS and PFS, supporting their role as prognostic biomarker.

在各种人类恶性肿瘤中都检测到CD155 / TIGIT过表达；然而，其在食管原发性小细胞癌（PSCCE）中的表达状态及其预后意义仍不清楚。在这项研究中，我们旨在探讨CD155和TIGIT在PSCCE中的表达及其预后价值。我们使用免疫组织化学（IHC）检测了114例PSCCE患者中的CD155和TIGIT表达，并评估了它们与临床病理特征和患者生存率的关系。使用Kaplan-Meier方法和Cox比例风险模型进行生存分析。通过一致性指数（C指数）和校准图评估了线型图的性能。进行决策曲线分析（DCA）以评估列线图的净收益。p<0.001），并且与肿瘤大小，T分期，远处转移，TNM分期和Ki-67得分显着相关。TIGIT表达也与T期，远处转移和TNM期显着相关。高CD155和TIGIT表达的患者的总生存期（OS）和无进展生存期（PFS）明显缩短，而多变量模型显示CD155表达和治疗策略是PSCCE的独立预后因素。在验证步骤中，显示OS校准良好（C指数= 0.724），并且DCA证明了令人满意的临床实用性。总之，我们的研究结果表明CD155和TIGIT在PSCCE患者中高表达，并与较短的OS和PFS相关，支持其作为预后生物标志物的作用。