ETV6::NTRK3 gene fusion in a patient with metastatic lung atypical carcinoid successfully treated with repotrectinib: A case report

Introduction: Chromosomal rearrangements involving the neurotrophin kinase (NTRK) genes NTRK1, NTRK2 and NTRK3 with different fusion partners occur in non-small cell lung cancers (NSCLCs) and other solid tumors. Novel NTRK rearrangement-related tumors are still being discovered.Methods: Herin, we describe a male patient with a mass in the left upper lobe that was biopsied by bronchoscopy. This case was diagnosed with stage IV lung atypical carcinoid (AC) harboring the ETV6::NTRK3 gene fusion.Results: He received 1st line treatment with everolimus lasting for 4 months. After chemotherapy failure, he received 3rd treatment with VC004 in a phase 1/2 study and achieved stable disease, but he stopped taking it due to intolerance. He subsequently received repotrectinib treatment and achieved a partial response of more than ten months.Conclusions: To the best of our knowledge, we reported the first case demonstrating anti-tumor activity of repotrectinib in a patient with AC carring an ETV6-NTRK3 gene fusion, indicating that repotrectinib may be an efficient therapeutic option for tumors with NTRK gene rearrangements.