ALK rearrangement
Pronunciation: A-L-K
Also written as: ALK — Anaplastic Lymphoma Kinase
A chromosomal abnormality involving the ALK gene, found in approximately 5% of lung adenocarcinomas and targetable with specific inhibitors.
Full Definition
ALK rearrangements result from chromosomal inversions or translocations that create fusion proteins, most commonly EML4-ALK. These genetic alterations are typically found in younger patients, never-smokers, and those with adenocarcinoma histology. ALK-positive tumors respond dramatically to ALK inhibitors like crizotinib, alectinib, and lorlatinib, making accurate detection by fluorescence in situ hybridization (FISH) or immunohistochemistry essential for treatment planning.
Usage
Usage note: ALK should be capitalized. Use 'rearrangement' rather than 'mutation' for technical accuracy.
In Context
- "FISH testing confirmed ALK rearrangement in the tumor specimen." — Molecular pathology report
- "The patient achieved dramatic response to alectinib for ALK-positive disease." — Treatment response note