Chronic Lymphocytic Leukemia FISH
| Item | Value | ||||
|---|---|---|---|---|---|
| Approval req'd? | Yes, contact Hematology at x3-1747 | ||||
| Available Stat? | No | ||||
| Test code | MOLT | ||||
| Performed by | Genzyme Genetics | ||||
| Sendout? | Yes | ||||
| Method | Fluorescent in situ hybridization | ||||
| Container type | Dark Green top (Lavender top acceptable for non-B&T patients) | ||||
| Amount to Collect | 10 mL blood or 3 mL bone marrow aspirate | ||||
| Collection Instructions | Dues to sample stability issues it is preferred that samples be submitted Monday through Thursday only. Bring immediately to laboratory for processing |
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| Sample type | Blood or bone marrow aspirate | ||||
| Preferred volume |
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| Min. Volume |
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| Normal range | Negative for each marker | ||||
| Synonyms | CLL FISH; del 17p13; del 11q22; del 13q14; +12; trisomy 12 | ||||
| Causes for rejection | Frozen or room temperature sample | ||||
| Additional information | Panel includes FISH probes to detect: del 17p13, del 11q22, +12 and del 13q14. Conventional cytogenetics studies identify chromosomal abnormalities in 30%-40% CLL cases. FISH has been reported to idetify abnormalities in approximately 80% of cases. This difference likely reflects the poor ability of CLL cells to grow in culture or the cryptic nature of the abnormalities. Based on current literature, four major prognostic groups can be identified with this panel of probes: cases exhibiting del 17p13, del 11q22 or +12 are associated poor clinical outcomes regarding disease progression and overall survival. Specifically the del 17p13 (p53) demonstrate poor response to fludarabine or rituximab (anti-CD20) although alemtuzumab (anti-CD52) may be efficacious. Conversely cases with del 13q14 have a good prognosis. Note that this panel of probes serves to provide prognostic information in patients with diagnosed CLL but has no use in the diagnosis of this disorder as these genetic abnormalities are not specific for CLL. |