Test Id : MPLVS
MPL Exon 10 Mutation Detection, Varies
Useful For
Suggests clinical disorders or settings where the test may be helpful
Aiding in the distinction between a reactive cytosis and a myeloproliferative neoplasm
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For more information see:
-Myeloproliferative Neoplasm: A Diagnostic Approach to Bone Marrow Evaluation
-Myeloproliferative Neoplasm: A Diagnostic Approach to Peripheral Blood Evaluation
Method Name
A short description of the method used to perform the test
Sanger Sequencing
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
MPL S505
MPL W515
MPLB
MPLM
MPLVA
Myeloproliferative leukemia virus oncogene
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For more information see:
-Myeloproliferative Neoplasm: A Diagnostic Approach to Bone Marrow Evaluation
-Myeloproliferative Neoplasm: A Diagnostic Approach to Peripheral Blood Evaluation
Specimen Type
Describes the specimen type validated for testing
Varies
ORDER QUESTIONS AND ANSWERS
| Question ID | Description | Answers |
|---|---|---|
| MP051 | Specimen Type |
Peripheral blood Bone marrow Extracted DNA from blood Extracted DNA from bone marrow |
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Submit only 1 of the following specimens:
Specimen Type: Peripheral blood
Container/Tube: Lavender top (EDTA) or yellow top (ACD)
Specimen Volume: 3 mL
Collections Instructions:
1. Invert several times to mix blood.
2. Send specimen in original tube. Do not aliquot.
3. Label specimen as blood.
Specimen Stability: Ambient (preferred)/Refrigerate
Specimen Type: Bone marrow
Container/Tube: Lavender top (EDTA) or yellow top (ACD)
Specimen Volume: 2 mL
Collections Instructions:
1. Invert several times to mix bone marrow.
2. Send specimens in original tube. Do not aliquot.
3. Label specimen as bone marrow.
Specimen Stability: Ambient (preferred)/Refrigerate
Specimen Type: Extracted DNA from blood or bone marrow
Container/Tube: 1.5- to 2- mL tube
Specimen Volume: Entire specimen
Collection Instructions: Label specimen as extracted DNA from blood or bone marrow and provide indication of volume and concentration of DNA.
Specimen Stability Information: Frozen (preferred)/Refrigerated/Ambient
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.
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.
Blood, Bone marrow: 0.5 mL; Extracted DNA: 50 mcL at 20 ng/mcL concentration
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Gross hemolysis | Reject |
| Bone marrow biopsies Slides paraffin shavings 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 |
|---|---|---|---|
| Varies | Varies | 7 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Aiding in the distinction between a reactive cytosis and a myeloproliferative neoplasm
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For more information see:
-Myeloproliferative Neoplasm: A Diagnostic Approach to Bone Marrow Evaluation
-Myeloproliferative Neoplasm: A Diagnostic Approach to Peripheral Blood Evaluation
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
DNA sequence variants in exon 10 of the myeloproliferative leukemia virus oncogene (MPL) have been detected in approximately 5% of patients with primary myelofibrosis (PMF) and essential thrombocythemia (ET), which are hematopoietic neoplasms classified within the broad category of myeloproliferative neoplasms. MPL codes for a transmembrane tyrosine kinase, and the most common MPL variants are single base pair substitutions at codon 515. These alterations have been shown to promote constitutive, cytokine-independent activation of the JAK/STAT signaling pathway and contribute to the oncogenic phenotype. At least 8 different MPL exon 10 variants have been identified in PMF and ET to date, and variants outside of exon 10 have not yet been reported. The vast majority of MPL variants have been found in specimens testing negative for the most common variant identified in myeloproliferative neoplasms, JAK2 V716F, although a small number of cases with both types of variants have been reported. MPL variants have not been identified in patients with polycythemia vera, chronic myelogenous leukemia, or other myeloid neoplasms.
Identification of MPL variants can aid in the diagnosis of a myeloproliferative neoplasm and is highly suggestive of either PMF or ET.
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 results will be reported as 1 of 2 states:
-Negative for MPL exon 10 variant
-Positive for MPL exon 10 variant
If the result is positive, a description of the variant at the nucleotide level and the altered protein sequence is reported.
Positive variant status is highly suggestive of a myeloproliferative neoplasm but must be correlated with clinical and other laboratory features for a definitive diagnosis. Negative variant status does not exclude the presence of a myeloproliferative or other neoplasm.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
A positive result is not specific for a particular diagnosis and clinicopathologic correlation is necessary in all cases.
A negative result does not exclude the presence of a myeloproliferative or other neoplasm.
Supportive Data
Analytical sensitivity is approximately 20%, meaning there must be about 20% of the altered DNA in the specimen for reliable detection.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Defour JP, Chachoua I, Pecquet C, Constantinescu SN. Oncogenic activation of MPL/thrombopoietin receptor by 17 mutations at W515: implications for myeloproliferative neoplasms. Leukemia. 2016;30(5):1214-1216. doi:10.1038/leu.2015.271
2. Pikman Y, Lee BH, Mercher T, et al. MPLW515L is a novel somatic activating mutation in myelofibrosis with myeloid metaplasia. PLoS Med. 2006;3(7):e270
3. Pardanani AD, Levine RL, Lasho T, et al. MPL515 mutations in myeloproliferative and other myeloid disorders: a study of 1182 patients. Blood. 2006;108(10):3472-3476
4. Kilpivaara O, Levine RL. JAK2 and MPL mutations in myeloproliferative neoplasms: discovery and science. Leukemia. 2008;22(10):1813-1817. doi:10.1038/leu.2008.229
Method Description
Describes how the test is performed and provides a method-specific reference
Genomic DNA is extracted from the blood or bone marrow sample, and the MPL exon 10 amplified using standard polymerase chain reaction. The entire exon 10 sequence is obtained using Sanger sequencing with analysis on an automated genetic analyzer.(Unpublished Mayo method)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
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.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
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.
CPT codes are provided by the performing laboratory.
81339-MPL (myeloproliferative leukemia virus oncogene, thrombopoietin receptor, TPOR) (eg, myeloproliferative disorder), exon 10 sequence
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 |
|---|---|---|
| MPLVS | MPL Exon 10 Mutation Detection, V | 62948-5 |
| 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.
|
|---|---|---|
| MP051 | Specimen Type | 31208-2 |
| 602600 | Interpretation | 69047-9 |
| 602601 | Signing Pathologist | 19139-5 |