NTRK fusion
Pronunciation: N-T-R-K FYU-zhun
A rare chromosomal rearrangement involving neurotrophic receptor tyrosine kinase genes, found in lung cancers and targetable with TRK inhibitors.
Full Definition
NTRK fusions are rare but actionable genetic alterations found in less than 1% of lung cancers, involving genes NTRK1, NTRK2, or NTRK3. These fusions result in constitutive activation of TRK signaling pathways, driving tumor growth and survival. NTRK fusions can occur across multiple cancer types and are typically mutually exclusive with other driver mutations in lung cancer. Patients with NTRK fusion-positive tumors can be treated with selective TRK inhibitors such as larotrectinib or entrectinib, which have demonstrated impressive response rates across different tumor types. Detection requires specialized testing techniques including immunohistochemistry, fluorescence in situ hybridization, or next-generation sequencing.
Usage
Usage note: Specify which NTRK gene and fusion partner when known, as this may impact treatment selection.
In Context
- "The patient's adenocarcinoma harbored an ETV6-NTRK3 fusion, prompting treatment with larotrectinib." — Precision medicine consultation
- "NTRK immunohistochemistry was positive, leading to confirmatory testing that identified a TPM3-NTRK1 fusion." — Pathology report interpretation