FISH for ROS1 (6q22)
Test Mnemonic
ROS1
CPT Codes
- 88377 - QTY (1)
Aliases
- ROS1 gene rearrangement
- ROS1 gene rearrangement by FISH
Performing Laboratory
Cleveland Clinic Laboratories
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 4 slides | Paraffin block, formalin fixed | Slides | Ambient | Ambient | Pre and post H&E with four unstained slides |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 4 slides | Pre and post H&E with four unstained slides |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | Slides from FFPE Tissue at room temp |
Days Performed
3 - 5 times per week
Turnaround Time
5 - 7 days
Methodology
| Name | Description |
|---|---|
| Fluorescent In-Situ Hybridization (FISH) |
Reference Range
Special Info
Pre and post H&E with four unstained slides
Clinical Info
ROS1 (ROS proto-oncogene 1, receptor tyrosine kinase) is located at chromosome 6q22 and encodes a receptor tyrosine kinase of the insulin receptor superfamily, the function of which is presently unknown. ROS1 rearrangements are present in approximately 1 - 2% of lung adenocarcinoma cases, and are more common in younger patients without a history of cigarette smoking. Rearrangements can involve multiple fusion partners, and result in constitutive activation of the ROS1 enzyme, leading to upregulation of pathways involved in cellular proliferation, differentiation, and survival. ROS1 rearrangements appear to be associated with responsiveness to tyrosine kinase inhibitors such as crizotinib.
Clinical Reference
Shaw AT, Sai-Hong IOU, Yung-Jue B, et al. Crizotinib in ROS1-Rearranged Non–Small-Cell Lung. National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology, Non-Small Cell Lun