Probes: SS18 (SYT) (18q11.2)
Disease(s): Synovial sarcoma
SS18 break-apart FISH testing detects rearrangements of SS18 (also known as SYT or SSXT) in synovial sarcoma. SS18 rearrangements are found exclusively in this tumor and have been widely used to establish an accurate diagnosis. The major translocation in synovial sarcoma is t(X;18)(p11.2;q11.2) which results in fusion of SS18 with one of the SSX genes on the X chromosome. This translocation or complex variants are present in >95% of all cases, often as the sole abnormality. SS18 rearrangement partners will not be identified by this FISH test. For that purpose, please see the NGS Comprehensive Sarcoma Fusion Profile.
- Bone marrow aspirate: N/A
- Peripheral blood: N/A
- Fresh, unfixed tissue: N/A
- Fluids: N/A
- Paraffin block: Send paraffin block. Also send circled H&E slide for tech-only (required)
- Cut slides: H&E slide (required) plus 4 unstained slides cut at 4-5 microns. Circle H&E slide for tech-only
Refrigerate specimen. Do not freeze. Use cold pack for transport, making sure cold pack is not in direct contact with specimen.