NRG1 fusion
Pronunciation: N-R-G-one FYU-zhun
A rare chromosomal rearrangement involving the neuregulin-1 gene, found in a small subset of lung adenocarcinomas and potentially targetable.
Full Definition
NRG1 fusions are rare oncogenic drivers found in approximately 0.2-0.3% of lung adenocarcinomas, typically occurring in younger patients and never-smokers. These fusions result in overexpression of the neuregulin-1 protein, which activates HER2 and HER3 signaling pathways leading to tumor growth and progression. The most common fusion partner is CD74, though other partners have been identified. Due to their rarity, treatment approaches are still being defined, but HER2-directed therapies such as afatinib have shown promise in early clinical studies. NRG1 fusions are mutually exclusive with other common driver mutations, highlighting the importance of comprehensive molecular testing.
Usage
Usage note: Emphasize rarity and emerging therapeutic options when documenting.
In Context
- "The rare NRG1 fusion was identified through comprehensive genomic profiling, leading to enrollment in a targeted therapy trial." — Clinical trial documentation
- "CD74-NRG1 fusion was detected in the patient's adenocarcinoma, prompting consideration of HER2-directed therapy." — Molecular tumor board discussion