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HelpOrder Code BCRAB BCR/ABL1, p210, mRNA Detection, Reverse Transcription-PCR (RT-PCR), Quantitative, Monitoring Chronic Myeloid Leukemia (CML), Varies
Reporting Name
BCR/ABL1, p210, Quant, MonitorUseful For
Monitoring response to therapy in patients with chronic myeloid leukemia who are known to have the e13/a2 or e14/a2 BCR/ABL1 fusion transcript forms
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
VariesShipping Instructions
Specimen must arrive within 72 hours of collection. Collect and package specimen as close to shipping time as possible. Specimens greater than 3 days old at the time of receipt will be considered unacceptable.
Necessary Information
Pertinent clinical history including if the patient has a diagnosis of chronic myeloid leukemia or other BCR/ABL1-positive neoplasm information is required.
Specimen Required
Submit only 1 of the following specimens:
Specimen Type: Whole blood
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Yellow top (ACD)
Specimen Volume: 10 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
3. Label specimen as blood.
Specimen Type: Bone marrow
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Yellow top (ACD)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix bone marrow.
2. Send bone marrow specimen in original tube. Do not aliquot.
3. Label specimen as bone marrow.
Specimen Minimum Volume
Blood: 4 mL
Bone marrow: 1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Refrigerated (preferred) | 72 hours | PURPLE OR PINK TOP/EDTA |
| Ambient | 72 hours | PURPLE OR PINK TOP/EDTA |
Special Instructions
Reference Values
The presence or absence of BCR/ABL1 mRNA fusion form e13/e14-a2 producing the p210 fusion protein is identified. If positive, the quantitative level is reported as the normalized ratio of BCR/ABL1 (p210) to endogenous ABL1 mRNA with conversion to a percentage referenced to the international scale (IS), on which 0.1% BCR/ABL1:ABL1 (also represented on a log scale as Molecular Response 3, or MR3) is designated as a major molecular response (MMR) threshold.
Day(s) Performed
Monday through Saturday
CPT Code Information
81206
Method Description
The assay is performed using an automated platform, GeneXpert (Cepheid). Four mL of whole blood is processed, added to an individual sample cartridge and loaded onto the GeneXpert machine. All subsequent reactions are performed within the cartridge and the results are processed and calculated by the instrument. Within the cartridge, RNA is extracted and converted to complementary DNA (cDNA).
Quantitative, reverse transcription polymerase chain reaction (PCR) is performed with a nested PCR reaction containing primers designed to amplify cDNA from the e13/a2 and e14/a2 BCR/ABL1 fusion products. A fragment of ABL1 cDNA is also amplified as a control for RNA degradation and for normalization of BCR/ABL1 results. The ratio of BCR/ABL1 (p210) to ABL1 is calculated from the difference in the crossing thresholds of BCR/ABL1 (p210) and ABL1 products in relation to a lot-specific standard curve, referenced to the international scale (IS). Lot-to-lot variation in the cartridges is corrected using a calibration calculation to reference standard curve data to the IS provided by the manufacturer.(Unpublished Mayo method)
Reject Due To
| Gross hemolysis | Reject |
| Moderately to severely clotted | Reject |
Method Name
Quantitative Reverse Transcription-Polymerase Chain Reaction (RT-PCR)
Forms
1. Hematopathology Patient Information (T676)
2. If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.
Testing Algorithm
For information see BCR/ABL1 Ordering Guide for Blood and Bone Marrow.