PDGFB (22q13), Dermatofibrosarcoma Protuberans/Giant Cell Fibroblastoma, FISH, Tissue
Use
This test is useful for identifying PDGFB gene rearrangements or amplification, confirming the diagnosis of dermatofibrosarcoma protuberans (DFSP) or giant cell fibroblastoma (GCF), and distinguishing these conditions from other spindle neoplasms that may have similar histological features. The rearrangement is commonly associated with specific chromosomal translocations that result in the formation of a chimeric gene, which is a characteristic finding in approximately 90% of DFSP cases and its related giant cell fibroblastoma form, but not in other tumors.
Special Instructions
A pathology report is required to perform this test; the report must include patient name, block number, date of collection, and tissue source. Pathology consultation is not included in this test and must be ordered separately if needed. It includes charges for probe application, analysis, and professional interpretation.
Limitations
This test is not FDA-approved and is intended to be used as an adjunct to existing clinical and pathological information. The FISH assay will not detect other chromosomal abnormalities beyond those specified, and tissue fixation methods other than formalin may impact test success. FISH studies on decalcified tissues have a 50% success rate. The pathology review may result in test cancellation if insufficient tissue is present.
New York Approved
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
LOINC Codes
- 50397-9
- 69965-2
- 62356-1
- 31208-2
- 80398-1
- 19139-5
- 42349-1
- 85069-3
- 48767-8
- 62364-5
Result Turnaround Time
7-10 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (FFPE)
Volume
Not provided
Minimum Volume
Not provided
Collection Instructions
Submit a formalin-fixed, paraffin-embedded tumor tissue block. Blocks prepared with alternative fixation methods will be attempted but are less favorable for successful results. Provide fixation method used.
Storage Instructions
Ambient (preferred)
Causes for Rejection
All specimens will be evaluated for test suitability at Mayo Clinic Laboratories.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Ambient |