Myelodysplastic Syndrome FISH Panel by Fluorescence In Situ Hybridization (FISH) Analysis
Monosomy 5/5q deletion, Monosomy 7/7q deletion, trisomy 8, chromosome 20q deletion, chromosome 11q deletion (MLL gene), Monosomy 13/chromosome 13q deletion, RPN1/MECOM, p53/CEP17, With Chrom: EPIC: LAB6470, SOFT: GMDSP, Without Chrom: EPIC:LAB6672, SOFT: GMDS2
Specimen Collection Criteria
Collect: Peripheral blood or bone marrow aspirate in a Dark Green-top Sodium Heparin tube. (Min: 1.0 mL)
A copy of the requisition must be sent with the specimen.
FedEx Shipping Instructions
Transport 1-2 mL bone marrow or 5-7 mL whole blood (minimum: 3 mL) at room temperature. If the specimen will not be received at the testing laboratory within 48 hours of collection, transport refrigerated. Do not fix or freeze the specimen. A pathology report for the patient must be provided.
Read our complete shipping instructions.
Physician Office/Drawsite Specimen Preparation
Do not freeze specimen. Maintain specimens at room temperature (20-25°C or 68-77°F) prior to courier pickup. For delays in transport (greater than 48 from the time of collection), refrigerate (2-8°C or 36-46°F) the specimen.
Preparation for Courier Transport
Transport: Peripheral blood or bone marrow, at room temperature (20-26°C or 68-78.8°F) or refrigerated (2-8°C or 36-46°F).
- Specimens arriving in the Laboratory 4 days or more following the original collection date.
- Fixed or frozen specimens.
Specimen Stability for Testing:
Room Temperature (20-26°C or 68-78.8°F): 48 hours
Refrigerated (2-8°C or 36-46°F): 96 hours
Frozen (-20°C/-4°F or below): Unacceptable
Specimen Storage in Department Prior to Disposal:
Refrigerated (2-8°C or 36-46°F): 7 days. A backup cell pellet is maintained for two weeks after the case has been signed out.
Royal Oak Clinical Cytogenomics Laboratory.
Monday - Friday, 8:00 a.m. - 5:00 p.m.
Results available within 7 days of receipt in the Laboratory.
Positive or negative for a neoplastic clone. An interpretative report will be provided.
Fluorescence In Situ Hybridization (FISH) Analysis.
A positive FISH result indicates the presence of the chromosome abnormality. A good prognosis is predicted with a normal karyotype, del(5q) or del(20q); an intermediate prognosis with trisomy 8; and a poor prognosis with chromosome 7 abnormalities and MLL gene deletion.
Bone marrow cytogenetic analysis is a standard practice in the evaluation of a patient with suspected myelodysplastic syndrome (MDS) and is considered an independent predictor of clinical outcome, overall survival, and progression to acute leukemia. Conventional cytogenetic analysis has identified chromosome abnormalities in approximately 40-70% of de novo MDS cases and in 95% of therapy-related MDS at diagnosis, with no abnormality specific for a particular MDS subtype with the exception of the chromosome 5q deletion. Recurrent chromosome changes in MDS include loss of chromosomes 5 or 7, deletions of chromosomes 5q or 7q, inv(3)(q21q26)/t(3;3)(q21;q26) trisomy 8, p53 gene deletion, and chromosome 20q deletion. Loss of the Y chromosome is also relatively common in MDS, but this is likely an age-related artifact in most patients.
The primary utility of FISH analysis in MDS is based on the finding that 15-20% of MDS patients demonstrate a normal karyotype, yet possesses one or more clonal abnormalities of prognostic and/or therapeutic significance when analyzed by FISH. In addition, the subset of MDS patients positive for one or more abnormalities by FISH but with a normal karyotype has demonstrated an increase in bone marrow blasts, an increased rate of leukemic transformation, and a poorer prognosis. Based on this and other studies, most advocate the use of an MDS FISH panel on the diagnostic specimen. The MDS FISH panel includes probes to detect -5/5q-, -7/7q-, trisomy 8, inv(3)(q21q26) or t(3;3)(q21;q26), chromosome 20q deletion, chromosome 11q deletion (MLL gene), p53 gene deletion, and chromosome 13q deletion.
- Bernasconi P et al (2006): Clinical relevance of cytogenetics in myelodysplastic syndromes. Ann NY Acad Sci 1089: 395-410.
- Rigolin GM et al (2001): Clinical importance of interphase cytogenetics detecting occult chromosome lesions in myelodysplastic syndromes with normal karyotype. Leukemia 15: 1841-1847.
88271x13 DNA probe, each, 88275x7 Interphase analysis, 100-300 cells.
With Chrom: EPIC: LAB6470, SOFT: GMDSP, Without Chrom: EPIC:LAB6672, SOFT: GMDS2