A liquid biopsy signature predicts lymph node metastases in T1 oesophageal squamous cell carcinoma: implications for precision treatment strategy.

ABSTRACT

BACKGROUND: The treatment strategies for T1 oesophageal squamous cell carcinoma (ESCC) patients with or without lymph node metastasis (LNM) are different. Given the advantages of the minimally invasive, sensitive and real-time detection, liquid biopsy has become an important cancer diagnostic and prognostic tool. METHODS: MiRNA array and small-RNA sequencing were performed. Then, 222 formalin-fixed and paraffin-embedded tumour samples and 229 pretreatment serum samples from T1 ESCC patients were used to verify and evaluate the results. RESULTS: We demonstrated that serum miR-20b-5p could predict LNM in T1 ESCC patients. The AUC for serum miR-20b-5p was higher (0.827) than those for lymphovascular invasion (LVI) (0.751, P = 0.2128), invasion depth (0.662, P = 0.0027) and tumour differentiation grade (0.634, P = 0.0019). A nomogram for predicting LNM with three independent significant predictors (miR-20b-5p, LVI and invasion depth) was constructed with a concordance index of 0.931. Serum miR-20b-5p was also significantly correlated with disease-free survival (P < 0.001). An algorithm of improved T1 ESCC treatment strategy after biopsy and/or after endoscopic resection based on serum miR-20b-5p level was constructed. CONCLUSIONS: This study suggests that serum miR-20b-5p is a potential biomarker for predicting LNM and can be helpful for precise clinical decision-making strategies and improve treatment outcomes for T1 ESCC patients.