Order Code LABCMAPT Chromosomal Microarray, Tumor, Formalin-Fixed Paraffin-Embedded
Useful For
Genomic characterization of tumor for copy number imbalances and loss of heterozygosity
Assisting in the diagnosis and classification of malignant neoplasms
Evaluating the prognosis for patients with malignant tumors
Testing Algorithm
This test does not include a pathology consult. If a pathology consultation is requested, PATHC / Pathology Consultation should be ordered, and the appropriate fluorescence in situ hybridization (FISH) test will be ordered and performed at an additional charge.
Hematoxylin and eosin stain review of the paraffin-embedded sample is performed to identify the area of invasive tumor prior to DNA extraction and microarray analysis. If additional FISH testing is requested, it will be performed at an additional charge.
For more information see Aggressive B-cell Lymphoma Diagnostic Algorithm.
Method Name
Chromosomal Microarray (CMA)
Reporting Name
Chromosomal Microarray, Tumor, FFPESpecimen Type
VariesOrdering Guidance
This test is not performed on fresh tissue specimens. If testing is needed for fresh tissue specimens, order CMAT / Chromosomal Microarray, Tumor, Fresh or Frozen.
If a fresh tissue specimen is submitted, this test will be canceled and CMAT will be performed and charged.
Necessary Information
A reason for testing and pathology report are required for testing to be performed. Send information with specimen. Acceptable pathology reports include working drafts, preliminary pathology or surgical pathology reports.
Specimen Required
Submit only 1 of the following specimens:
Specimen Type: Tissue
Container/Tube: Formalin-fixed, paraffin-embedded tumor tissue block
Specimen Type: Slides
Specimen Volume: 10 Consecutive, unstained, 5-micron-thick sections placed on positively charged slides and 1 hematoxylin and eosin-stained slide
Specimen Minimum Volume
See Specimen Required
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Varies | Ambient (preferred) | |
Refrigerated |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
An interpretive report will be provided.
Method Description
The selection of tissue and the identification of invasive tumor on the hematoxylin and eosin (H and E)-stained slide are performed by a pathologist. Using the H and E slide as a reference, the target areas are marked on the unstained slide, the DNA is extracted from the tumor is labeled and hybridized to the microarray. Following hybridization, the microarray is scanned, and the intensity of signals is measured and compared to a reference data set. These data are used to determine copy number changes and regions with loss of heterozygosity. Chromosomal microarray data alone does not provide information about the structural nature of an imbalance. Thus, it may be of benefit to utilize fluorescence in situ hybridization or additional techniques to further characterize a patient sample.(Unpublished Mayo method)
Day(s) Performed
Monday through Friday
Performing Laboratory

CPT Code Information
81277
Special Instructions
Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.