Rare event of NTRK3 rearrangement and amplification in esophageal squamous cell carcinoma

Background: TRK tyrosine kinase inhibitors (larotrectinib or entrectinib) can cause an unknown histological response in NTRK fusion-positive cancer patients,and it has been approved by the US Food and Drug Administration.The neurotrophic tyrosine kinase receptor (NTRK) 3 gene rearrangements is a target of tyrosine kinase inhibitors.We attempted to assess the correlation of NTRK3 gene rearrangement and gene copy number changes with ESCC prognosis.Methods: The tissue microarray of 478 cases was detected by fluorescence in situ hybridization (FISH) assay.Kaplan-Meier survival and Cox regression analysis were performed to evaluate the prognostic significance of NTRK3 rearrangement and amplification in esophageal squamous cell carcinoma.Results: This study show that both NTRK3 gene rearrangement and copy number variation are rare events in ESCC. Gene rearrangement and copy number changes have little influence on the prognosis.Except when gene copy number was greater than or equal to 4, patients with stage I+II showed a trend of poor prognosis (P=0.120; OS, P=0.095). Conclusion: NTRK3 gene rearrangement and gene copy number variation are rare in esophageal cancer, and gene rearrangement does not affect prognosis, while the number of gene copies was 4 as the threshold, there was a tendency of poor prognosis.