ROS1 rearrangement
A rare genetic alteration found in lung adenocarcinoma that predicts response to specific targeted therapies.
Full Definition
ROS1 rearrangements are oncogenic genetic alterations found in approximately 1-2% of lung adenocarcinomas, resulting from chromosomal translocations that create fusion proteins with constitutive kinase activity. Like ALK rearrangements, ROS1 fusions are more commonly found in younger patients, never-smokers, and those with adenocarcinoma histology. Detection requires specialized molecular testing techniques such as fluorescence in situ hybridization (FISH), immunohistochemistry, or next-generation sequencing. Patients with ROS1-positive tumors respond well to targeted therapy with crizotinib and other ROS1 inhibitors, making accurate identification clinically crucial for treatment planning.
Usage
Usage note: Capitalize ROS1 as a gene name; specify the fusion partner when known (e.g., CD74-ROS1).
In Context
- "Molecular testing identified a CD74-ROS1 rearrangement, making the patient eligible for targeted therapy." — Molecular pathology report
- "The tumor was negative for EGFR mutations but positive for ROS1 rearrangement by FISH." — Genomic profiling summary