Test Catalog

Test Id : CALJM

Not Orderable

CALR Variant Analysis, Myeloproliferative Neoplasm, Reflex, Bone Marrow

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Overview

Test Catalog

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

Aiding in the distinction between a reactive cytosis and a chronic myeloproliferative disorder

 

Evaluating for variants in CALR in an algorithmic process

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

Only orderable as a reflex. For more information see MPNJM / Myeloproliferative Neoplasm, JAK2 V617F with Reflex to CALR and MPL, Bone Marrow.

 

Polymerase Chain Reaction (PCR)/Fragment Analysis

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

CALR, Gene Mutation, Exon 9, BM

Specimen Type
Describes the specimen type validated for testing

Bone Marrow

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: 2 mL

Collection Instructions:

1. Invert several times to mix bone marrow.

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

3. Label specimen as bone marrow.

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.

0.5 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 (preferred) 7 days
Refrigerated 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 chronic myeloproliferative disorder

 

Evaluating for variants in CALR in an algorithmic process

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

The Janus kinase 2 gene (JAK2) codes for a tyrosine kinase (JAK2) that is associated with the cytoplasmic portion of a variety of transmembrane cytokine and growth factor receptors important for signal transduction in hematopoietic cells. Signaling via JAK2 activation causes phosphorylation of downstream signal transducers and activators of transcription (STAT) proteins (eg, STAT5) ultimately leading to cell growth and differentiation. BCR-ABL1-negative myeloproliferative neoplasms (MPN) frequently harbor an acquired single nucleotide variant in JAK2 characterized as c.G1849T; p. Val617Phe (V617F). JAK2 V617F is present in 95% to 98% of polycythemia vera and 50% to 60% of primary myelofibrosis (PMF) and essential thrombocythemia (ET). It has also been described infrequently in other myeloid neoplasms, including chronic myelomonocytic leukemia and myelodysplastic syndrome. Detection of JAK2 V617F is useful to help establish the diagnosis of MPN. However, a negative JAK2 V617F result does not indicate the absence of MPN. Other important molecular markers in BCR-ABL1-negative MPN include CALR exon 9 variant (20%-30% of PMF and ET) and MPL exon 10 variant (5%-10% of PMF and 3%-5% of ET). Variants in JAK2, CALR, and MPL are essentially mutually exclusive. A CALR variant is associated with decreased risk of thrombosis in both ET and PMF and confers a favorable clinical outcome in PMF patients. A triple negative (JAK2 V617F, CALR, and MPL-negative) genotype is considered a high-risk molecular signature in PMF.

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.

Only orderable as a reflex. For more information see MPNJM / Myeloproliferative Neoplasm (MPN), JAK2 V617F with Reflex to CALR and MPL, Bone Marrow. 

 

An interpretive report will be provided.

Interpretation
Provides information to assist in interpretation of the test results

An interpretation will be provided.

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 subtype of myeloproliferative neoplasm (MPN) and clinicopathologic correlation is necessary in all cases.

 

A negative result does not exclude the presence of a MPN or other neoplastic process.

 

This test is a fragment analysis assay and only detects deletions and insertions and deletions (delins). It will not detect point alterations. However, all reported disease-causing variants in MPN described to date are delins.

 

This test may not differentiate between out-of-frame and in-frame delins in rare cases. However, in-frame delins are very rare (<0.5%) and have only been reported in few healthy individuals and in MPN patients with JAK2V617F variant or out-of-frame CALR variant. Most of the rare in-frame delins are considered germline variants and represent nonpathogenic alterations.

 

Infrequently, amplification failure can be encountered in a given sample, due to inadequate DNA, poor DNA quality, or a polymerase chain reaction inhibitor. In these circumstances, the assay will be reattempted and if persistently unsuccessful, the report will be issued with an "Invalid" result.

Supportive Data

This assay has an analytical sensitivity of approximately 6% (ie, 6 variant-containing cells in 100 total cells) in most variant types, except for the rare type of 1-base pair deletion, which has a sensitivity of approximately 20%.

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

1. Klampfl T, Gisslinger H, Harutyunyan AS, et al. Somatic mutation of calreticulin in myeloproliferative neoplasms. N Engl J Med. 2013;369(25):2379-2390. doi:10.1056/NEJMoa1311347

2. Nangalia J, Massie CE, Baxter EJ, et al. Somatic CALR mutation in myeloproliferative neoplasms with nonmutated JAK2. N Engl J Med. 2013;369(25):2391-2405. doi:10.1056/NEJMoa1312542

3. Rumi E, Pietra D, Ferretti V, et al. JAK2 or CALR mutation status defines subtypes of essential thrombocythemia with substantially different clinical course and outcomes. Blood. 2014;123(10):1544-1551. doi:10.1182/blood-2013-11-539098

4. Rotunno G, Mannarelli C, Guglielmelli P, et al. Impact of calreticulin mutations on clinical and hematological phenotype and outcome in essential thrombocythemia. Blood. 2014;123(10):1552-1555. doi:10.1182/blood-2013-11-538983

5. Tefferi A, Lasho TL, Finke CM, et al. CALR vs JAK2 vs MPL-mutated or triple-negative myelofibrosis: clinical, cytogenetic and molecular comparisons. Leukemia. 2014;28(7):1472-1477. doi:10.1038/leu.2014.3

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

Polymerase chain reaction (PCR) amplification of CALR exon 9 is performed on DNA isolated from the patient sample. The PCR product is then run on an Applied Biosystems Genetic Analyzer for fragment analysis to detect insertions and deletions.(Unpublished Mayo method)

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

No

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.

7 to 10 days

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

DNA: 3 months

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.

81219-CALR (calreticulin) (eg, myeloproliferative disorders), gene analysis, common variants in exon 9

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
CALJM CALR, Gene Mutation, Exon 9, BM 77174-1
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.
614540 Final Diagnosis 22637-3

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