Belgian expert consensus for tumor-agnostic treatment of NTRK gene fusion-driven solid tumors with larotrectinib

Fusions of NTRK (neurotrophic tyrosine receptor kinase) genes with 5' partner genes can result in the expression of chimeric proteins that drive oncogenesis through ligand-independent kinase activation. Despite variable frequencies of NTRK fusions in different tumor types, the fact that they are common to a wide range of cancers raises the possibility of developing tumor-agnostic treatments specifically targeting NTRK fusion products, irrespective of tumor type. The first-generation Trk (tropomyosin receptor kinase) inhibitor, larotrectinib, was the first tumor-agnostic treatment of NTRK fusion-positive cancers in adults and children, to be approved in the European Union. This consensus, developed by a Belgian multidisciplinary expert panel, aims to highlight the unmet medical need associated to NTRK fusion-driven cancer treatment and, based on current knowledge of NTRK fusions and larotrectinib treatment outcome and safety, provide comprehensive guidance to oncologists regarding NTRK fusion-driven cancer diagnostics and the best use of larotrectinib in real-world clinical settings. Larotrectinib; NTRK gene fusion; Trk inhibitor; Tumor-agnostic; Expert opinion; Oncogene proteins; Protein kinase inhibitors.