Test Code CMAH Chromosomal Microarray, Hematologic Disorders, Varies
Useful For
Detection and characterization of clonal copy number imbalance and loss of heterozygosity associated with hematologic neoplasms
Assisting in the diagnosis and classification of certain hematologic neoplasms
Evaluating the prognosis for patients with certain hematologic neoplasms
Testing Algorithm
DNA extraction is always performed on the specimen prior to hybridization to the microarray. An unstimulated cell culture will be set up on all specimens with adequate volume and held pending additional testing. If additional testing is requested, such as karyotype analysis or fluorescence in situ hybridization, it will be performed at an additional charge.
The following algorithms are available:
Method Name
Chromosomal Microarray (CMA)
Reporting Name
Chromosomal Microarray, HematologicSpecimen Type
VariesOrdering Guidance
This test is not appropriate for detecting constitutional/congenital copy number changes or regions of excessive homozygosity. If this test is ordered with a reason for testing indicating a constitutional/congenital disorder, the test will be canceled and CMACB / Chromosomal Microarray, Congenital, Blood will be added and performed as the appropriate test.
Shipping Instructions
Advise Express Mail or equivalent if not on courier service.
Necessary Information
1. A reason for testing must be provided for testing to be performed.
2. A pathology report should accompany the specimen. If this information is not available at the time of order, submit as soon as possible for appropriateness of testing and to aid in interpretation of results.
Specimen Required
Submit only 1 of the following specimens:
Specimen Type: Bone marrow
Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA)
Specimen Volume: 1-2 mL
Collection Instructions:
1. Invert several times to mix bone marrow.
2. Send bone marrow specimen in original tube. Do not aliquot.
Specimen Type: Whole blood
Container/Tube:
Preferred: Green top (sodium heparin)
Acceptable: Lavender top (EDTA)
Specimen Volume: 7-10 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
Specimen Minimum Volume
Blood: 2 mL; Bone marrow: 1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Refrigerated |
Reference Values
An interpretive report will be provided.
Interpretation
The interpretive report describes copy number changes and any loss of heterozygosity that may be associated with the neoplastic process. Abnormal clones with subclonal cytogenetic evolution will be discussed if identified.
The continual discovery of novel copy number variation and published clinical reports means that the interpretation of any given copy number change may evolve with increased scientific understanding.
Although the presence of a clonal abnormality usually indicates a neoplasia, in some situations it may reflect a benign or constitutional genetic change. If a genetic change is identified that is likely constitutional and clearly pathogenic (eg, XYY), consultation with a Clinical Geneticist may be suggested.
The absence of an abnormal clone may be the result of specimen collection from a site that is not involved in the neoplasm or may indicate that the disorder is caused by a point mutation that is not detectable by chromosomal microarray.
Chromosomal microarray, fluorescence in situ hybridization (FISH), and conventional cytogenetics are to some extent complementary methods. In some instances, additional FISH or conventional cytogenetic studies will be recommended to clarify interpretive uncertainties.
Clinical Reference
1. Shao L, Akkari Y, Cooley LD, et al. ACMG Laboratory Quality Assurance Committee. Chromosomal microarray analysis, including constitutional and neoplastic disease applications, 2021 revision: a technical standard of the American College of Medical Genetics and Genomics (ACMG). Genet Med. 2021;23(10):1818-1829. doi:10.1038/s41436-021-01214-w
2. Peterson JF, Aggarwal N, Smith CA, et al. Integration of microarray analysis into the clinical diagnosis of hematological malignancies: How much can we improve cytogenetic testing?. Oncotarget. 2015;6(22):18845-18862
3. Mikhail FM, Biegel JA, Cooley LD, et al. Technical laboratory standards for interpretation and reporting of acquired copy-number abnormalities and copy-neutral loss of heterozygosity in neoplastic disorders: a joint consensus recommendation from the American College of Medical Genetics and Genomics (ACMG) and the Cancer Genomics Consortium (CGC). Genet Med. 2019;21(9):1903-1916
Day(s) Performed
Monday through Sunday
Report Available
7 to 14 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
81277
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CMAH | Chromosomal Microarray, Hematologic | 94087-4 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
54721 | Result Summary | 50397-9 |
54722 | Result | 62356-1 |
54723 | Nomenclature | 62378-5 |
54724 | Interpretation | 69965-2 |
CG902 | Reason for Referral | 42349-1 |
CG903 | Specimen | 31208-2 |
54725 | Source | 31208-2 |
54726 | Method | 85069-3 |
53423 | Additional Information | 48767-8 |
54727 | Released By | 18771-6 |
Special Instructions
Forms
If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.