FISH for RET Cyto Block
Test Mnemonic
RETCB
CPT Codes
- 88377 - QTY (1)
Includes
- LSI 10q11
Performing Laboratory
Cleveland Clinic Laboratories
FDA Category
Laboratory Developed Test
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 4 slides | cytologic preparation (slide) | Slides | Ambient | Ambient | Cytology cell blocks that have been formalin fixed OR 4 μm formalin fixed paraffin-embedded tissue sections on electrostatically charged slides containing representative tumor, including Pre-H&E. Samples must not be fixed in Prefer or B5. |
Stability
| Environmental Condition | Description |
|---|---|
| Refrigerated | Not preferred |
| Frozen | Unacceptable |
| Ambient | Cell block slides are acceptable |
Days Performed
5 days per week
Turnaround Time
5 - 7 days
Methodology
| Name | Description |
|---|---|
| Fluorescent In-Situ Hybridization (FISH) |
Clinical Info
Interphase FISH analysis utilizing a dual color, break-apart probe for the RET gene at 10q11.21. Rearrangements involving RET may be seen in individuals with late-stage, lung adenocarcinomas that are negative for EGFR and ALK rearrangements. The translocation partner gene cannot be identified in this assay. If no cells are available for analysis, no analysis charges will be incurred.
Clinical Limitation
This assay has been validated for cell blocks prepared from cytology samples fixed in PreservCyt solution using the Cellient Automated Cell Block System (Hologic, Marlborough, MA). Blocks prepared with other fixatives and/or methods are not acceptable.