Test Catalog

Test Id : P190M

Not Orderable

BCR::ABL1, p190, mRNA Detection, Reverse Transcription PCR, Quantitative, Monitoring Assay, Bone Marrow

Download
Overview

Test Catalog

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detection of e1/a2 BCR::ABL1 (p190) fusion at diagnosis of acute myeloid leukemia (ALL) and BCR::ABL1 (p210) negative chronic myeloid leukemia (CML) using bone marrow specimens

 

Monitoring response to therapy in patients with known e1/a2 BCR::ABL1 (p190) fusion forms in childhood ALL, adult ALL, and rare CML cases

Method Name
A short description of the method used to perform the test

Quantitative Reverse Transcription Polymerase Chain Reaction (RT-PCR)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

No

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

BCR/ABL1, p190, Quant, Monitor, BM

Aliases
Lists additional common names for a test, as an aid in searching

Acute lymphoblastic leukemia (ALL)

Acute myeloid leukemia (AML)

B lymphoblastic leukemia (B-ALL)

BCR ABL

BCR-ABL1

BCR/ABL

Philadelphia chromosome, Ph bone marrow/blood

T lymphoblastic leukemia (T-ALL)

t(9;22)

Specimen Type
Describes the specimen type validated for testing

Bone Marrow

Necessary Information

The following information is required:

1. Pertinent clinical history including if the patient has a diagnosis of chronic myeloid leukemia or other BCR::ABL1-positive neoplasm

2. Date of collection

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Container/Tube: Lavender top (EDTA)

Specimen Volume: 4 mL

Collection Instructions:

1. Invert several times to mix bone marrow.

2. Send bone marrow specimen in original tube. Do not aliquot.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.

1 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Moderately to severely clotted Reject

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Bone Marrow Ambient 72 hours
Refrigerated (preferred) 72 hours

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detection of e1/a2 BCR::ABL1 (p190) fusion at diagnosis of acute myeloid leukemia (ALL) and BCR::ABL1 (p210) negative chronic myeloid leukemia (CML) using bone marrow specimens

 

Monitoring response to therapy in patients with known e1/a2 BCR::ABL1 (p190) fusion forms in childhood ALL, adult ALL, and rare CML cases

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Messenger RNA (mRNA) transcribed from BCR::ABL1 (fusion of the breakpoint cluster region gene [BCR] at chromosome 22q11 to the Abelson gene [ABL1] at chromosome 9q34) is detected in all patients with chronic myeloid leukemia (CML) and a subset of patients with both acute lymphoblastic leukemia (ALL) and acute myeloid leukemia. Although breakpoints in the BCR and ABL1 genes may occur in a variety of locations, splicing of the primary RNA transcripts result in only 8 fusion site variants (e1/a2, e6/a2, e13/a2, e14/a2, e19/a2, and e1/a3, e13/a3, e14/a3), which incorporate the entire sequence of the exons on both sides of the fusion site. The e1/a2 and e1/a3 fusion forms produce a 190-kDa protein designated p190. This BCR::ABL1 protein form is found in approximately 75% of patients with childhood ALL and approximately 50% of patients with adult ALL, with the majority arising from e1/a2 mRNA. The p190 is also the predominant fusion form in a small subset of patients with CML, although the vast majority of CML cases contain the p210 protein, typically from e13/a2 or e14/a2 mRNA fusions. Other fusion forms are very rare.

 

Quantitative reverse-transcription polymerase chain reaction is the most sensitive method for monitoring BCR::ABL1 levels during treatment. This test detects mRNA coding for the most common p190 fusion form (e1/a2).

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

An interpretive report will be provided

Interpretation
Provides information to assist in interpretation of the test results

The interpretive report includes an overview of the findings.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

This test detects only the e1/a2 BCR::ABL1 (p190) fusion form. Other fusion forms are not detected by this assay, including those containing the BCR e13 and e14 exons, which code for the p210 protein commonly found in chronic myeloid leukemia, and the rare e1/a3 (p190) fusion form.

 

The precision of this assay at very low BCR::ABL1 levels is less reliable, such that interassay variation can be more variable. If the results are being used to make major therapeutic decisions, significant changes during monitoring should be verified with a subsequent specimen.

 

Results of this assay cannot be directly compared with results generated from other polymerase chain reaction (PCR) assays, including identical assays performed in other laboratories. Monitoring should be performed using the same method and laboratory for each subsequent specimen.

 

The results of this assay cannot be directly compared with BCR::ABL1 results obtained using fluorescence in situ hybridization (FISH) technology. FISH measures DNA alleles and this PCR-based assay measures messenger RNA (mRNA) transcripts. Because a single DNA allele can produce many mRNA transcripts, the values are not directly comparable.

 

Blood is the specimen of choice for monitoring. While most patients show similar BCR::ABL1 levels in blood and bone marrow collected at the same time, some patients have a consistent difference in the levels in blood and bone marrow such that altering specimen types during monitoring can lead to confusion.

 

Assay precision does not appear to be significantly affected by specimen transport or moderate delays in processing. However, in specimens with very low levels of BCR::ABL1, these conditions may cause sufficient RNA degradation to produce false-negative results. Thus, specimens should be shipped as quickly as possible. Ambient specimens received greater than 3 days  after specimen collection and refrigerate specimens received greater than 5 days after specimen collection are unacceptable.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Hughes TP, Kaeda J, Branford S, et al. Frequency of major molecular responses to imatinib or interferon alfa plus cytarabine in newly diagnosed chronic myeloid leukemia. N Engl J Med. 2003;349(15):1423-1432

2. Radich JP, Gooley T, Bryant E, et al. The significance of BCR/ABL molecular detection in chronic myeloid leukemia patients "late," 18 months or more after transplantation. Blood. 2001;98(6):1701-1707

3. Olavarria E, Kanfer E, Szydlo R, et al. Early detection of BCR-ABL transcripts by quantitative reverse transcriptase-polymerase chain reaction predicts outcome after allogeneic stem cell transplant for chronic myeloid leukemia. Blood. 2001;97(6):1560-1565

4. Tefferi A. The classic myeloproliferative neoplasms: Chronic myelogenous leukemia, polycythemia vera, essential thrombocythemia, and primary myelofibrosis. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA, eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019. Accessed November 27, 2024. Available at https://ommbid.mhmedical.com/content.aspx?sectionid=225078035&bookid=2709

Method Description
Describes how the test is performed and provides a method-specific reference

The assay is performed using an automated platform, GeneXpert (Cepheid). Bone marrow specimen is processed and 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 e1a2 fusion products. A fragment of ABL1 cDNA is also amplified as a control for RNA degradation and for normalization of BCR::ABL1 results.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

Supplemental

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

2 to 4 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

2 weeks

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Jacksonville

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

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
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

81207

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
P190M BCR/ABL1, p190, Quant, Monitor, BM 49795-8
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
618879 BCR/ABL1, p190 Result No LOINC Needed
618880 Final Diagnosis: 69047-9

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports