Molecular characteristics and multivariate survival analysis of 43 patients with locally advanced or metastatic esophageal squamous cell carcinoma.

BACKGROUND: Esophageal cancer (EC) is an aggressive malignant tumor with poor prognosis and high incidence. It is the sixth leading cause of cancer-related death in the world, and the 5-year overall survival (OS) rate is only 12-20%. The rapid development of next-generation sequencing (NGS) has provided powerful help for the treatment and management of EC patients.

METHODS: Tumor tissue and blood samples of 43 Chinese patients with nonsurgical esophageal squamous cell carcinoma (ESCC) were sequenced using a 425 gene-panel. Genomic profiling was explored and and the Cox proportional hazards model was used to analyze the correlations between gene or signaling pathway alterations and prognosis.

RESULTS: In this study, the most common mutated genes were TP53 (90.5%), CCND1 (45.2%), FGF19 (38.1%), NOTCH1 (26.2%), PI3KCA (21.4%) and CDKN2A (19%). Among these mutations, PI3KCA and NOTCH1 showed mutual exclusion to some extent. In the univariate model, mutations in NOTCH1 , CBLB and TSC2 genes and tumor mutation burden (TMB) ≥7 were independent biomarkers of OS. NOTCH1 (P=0.007, HR =2.87), CBLB (P=0.011, HR =4.68) and TSC2 (P=0.024, HR =3.7) were significantly associated with poorer OS, and patients with TMB ≥7 had longer OS (P=0.151, HR =0.31). In addition, patients who carried alteration in NOTCH signaling pathway had reduced OS (P=0.014, HR =2.54).

CONCLUSIONS: NOTCH1 , CBLB and TSC2 alterations were found to be potential indicators of poor prognosis in patients with ESCC. TMB was also positively correlated with the OS of ESCC patients, providing valuable insights for their treatment strategies.