FISH analysis for Acute Myeloid Leukaemia
|Category||Specialist Integrated Haematological Malignancy Diagnostic Service (SIHMDS) >> Cytogenetics|
FISH involves the application of fluorescent DNA probes specific to genes or genetic regions of interest that highlight abnormalities involving these regions.
Acute myeloid leukaemia (AML) is the most common acute leukaemia in adults and recurrent genomic findings define the classification of AML. Cytogenetic and FISH testing is delivered in line with the National Genomic Test Directory (NGTD) for Cancer.
A rapid FISH panel is performed on all diagnostic AML cases and is reported within 3 calendar days.
|Sample & container required||See notes section|
|Sample volume||Samples would not be rejected on the basis of small volume, however, 5 mL is ideal.|
|Turnaround time||See notes section|
Bone marrow in cytogenetic transport medium (preferred) or lithium heparin is usually the sample of choice, but peripheral blood in lithium heparin may be suitable if there are circulating blasts and/or a high white blood cell count. EDTA samples are only suitable in cases requiring FISH only (ie follow-up samples from patients with FISH-detectable abnormalities, or blood samples taken at diagnosis for exclusion of a specific gene fusion when a bone marrow sample will shortly follow). If in doubt please use lithium heparin. Samples which are non-sterile, clotted or collected in sodium citrate, fixative or saline are not suitable. To ensure appropriate analysis and interpretation it is important to provide clear and concise clinical information.
Rapid FISH tests (exclusion of specific genetic subtypes at diagnosis): 95% should be reported within 3 working days as a “preliminary result”. The remaining conventional cytogenetic analysis will be included in a final report, including any additional FISH, within 10 calendar days if rapid FISH was negative, or < 21 calendar days if rapid FISH was positive.
Post treatment follow-up samples are treated as routine; 95% should be reported within 21 calendar days.