Test Catalog

Test Id : PHLDF

Philadelphia Chromosome-like Acute Lymphoblastic Leukemia (Ph-like ALL), Diagnostic FISH, Varies

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

Detecting a neoplastic clone associated with Philadelphia chromosome-like acute lymphoblastic leukemia, particularly when a classic abnormality is not detected with the initial panel

 

An adjunct to conventional chromosome studies in patients with B-cell ALL

 

Evaluating specimens in which standard cytogenetic analysis is unsuccessful

Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.

Test Id Reporting Name Available Separately Always Performed
PHLDB Probe, Each Additional (PHLDF) No, Bill Only No

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

This test includes a charge for the probe application, analysis, and professional interpretation of results for 7 probe sets (14 individual fluorescence in situ hybridization [FISH] probes). Additional charges will be incurred for all reflex or additional probe sets performed.

 

The Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) panel includes testing for the following four kinase-activating chromosome rearrangements, as well as for IKZF1 deletion, which often accompanies Ph-like ALL:

1q25 rearrangement, ABL2

5q33 rearrangement, PDGFRB

9p24.1 rearrangement, JAK2

9q34 rearrangement, ABL1

7p-, IKZF1/CEP7

t(Xp22.33;var) or t(Yp11.32;var), CRLF2 rearrangement

t(Xp22.33;var) or t(Yp11.32;var), P2RY8 rearrangement

 

When a CRLF2 rearrangement is identified, reflex testing will be performed using the CRLF2/IGH fusion probe set to identify a potential t(X;14)(p22.33;q32) or t(Y;14)(p11.32;q32) cryptic translocation.

 

See B-Lymphoblastic Leukemia/Lymphoma Algorithm in Special Instructions.

Special Instructions
Library of PDFs including pertinent information and forms related to the test

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

Fluorescence In Situ Hybridization (FISH)

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

Yes

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

Ph-like ALL(B-cell), Diag FISH

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

ABL1 (9q34) rearrangement

ABL2 (1q25) rearrangement

BCR-ABL1 like ALL

JAK2 (9p24.1) rearrangement

PDGFRB (5q33) rearrangement

Ph-like ALL

Philadelphia-like ALL

CRLF2 (Xp22.33) or (Yp11.32) rearrangement

P2RY8 (Xp22.33) or (Yp11.32) rearrangement

t(X;14)(p22.3;q32) - CRLF2/IGH

t(Y;14)(p11.32;q32) - CRLF2/IGH

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

This test includes a charge for the probe application, analysis, and professional interpretation of results for 7 probe sets (14 individual fluorescence in situ hybridization [FISH] probes). Additional charges will be incurred for all reflex or additional probe sets performed.

 

The Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) panel includes testing for the following four kinase-activating chromosome rearrangements, as well as for IKZF1 deletion, which often accompanies Ph-like ALL:

1q25 rearrangement, ABL2

5q33 rearrangement, PDGFRB

9p24.1 rearrangement, JAK2

9q34 rearrangement, ABL1

7p-, IKZF1/CEP7

t(Xp22.33;var) or t(Yp11.32;var), CRLF2 rearrangement

t(Xp22.33;var) or t(Yp11.32;var), P2RY8 rearrangement

 

When a CRLF2 rearrangement is identified, reflex testing will be performed using the CRLF2/IGH fusion probe set to identify a potential t(X;14)(p22.33;q32) or t(Y;14)(p11.32;q32) cryptic translocation.

 

See B-Lymphoblastic Leukemia/Lymphoma Algorithm in Special Instructions.

Specimen Type
Describes the specimen type validated for testing

Varies

Ordering Guidance

This test is intended to be ordered when the entire Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like B-cell ALL) fluorescence in situ hybridization (FISH) panel is needed.

-If this test is ordered and the laboratory is informed that the patient is on a Children's Oncology Group (COG) protocol, this test will be canceled and automatically reordered by the laboratory as COGBF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Children's Oncology Group Enrollment Testing, FISH, Varies.

 

If limited Ph-like B-cell ALL FISH probes are preferred, order BALMF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Specified FISH, Varies.

 

At diagnosis, conventional cytogenetic studies (CHRBM / Chromosome Analysis, Hematologic Disorders, Bone Marrow) and a complete B-ALL FISH panel, either BALAF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), FISH, Adult, Varies or BALPF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), FISH, Pediatric, Varies, depending on the age of the patient, should be performed.

 

At follow-up, conventional cytogenetic studies (CHRBM / Chromosome Analysis, Hematologic Disorders, Bone Marrow) and targeted B-ALL FISH probes can be evaluated based on the abnormalities identified in the diagnostic study. Order BALMF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Specified FISH, Varies and request specific probes or abnormalities.

 

If the patient clinically relapses, a conventional chromosome study may be useful to identify cytogenetic changes in the neoplastic clone or the possible emergence of a therapy-related myeloid clone.

 

For patients with B-cell lymphoma, order BLPMF / B-Cell Lymphoma, Specified FISH, Varies.

 

For testing paraffin-embedded tissue samples from patients with B-cell lymphoblastic lymphoma, order BLBLF / B-Cell Lymphoblastic Leukemia/Lymphoma, FISH, Tissue.

Shipping Instructions

Advise Express Mail or equivalent if not on courier service.

Necessary Information

A reason for testing and a flow cytometry and/or a bone marrow pathology report should be submitted with each specimen. The laboratory will not reject testing if this information is not provided, however appropriate testing and interpretation may be compromised or delayed in the absence of this information. If this information is not provided, an appropriate indication for testing may be entered by Mayo Clinic Laboratories.

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:

 

Preferred

Specimen Type: Bone marrow

Container/Tube:

Preferred: Yellow top (ACD)

Acceptable: Green top (heparin) or lavender top (EDTA)

Specimen Volume: 2-3 mL

Collection Instructions:

1. It is preferable to send the first aspirate from the bone marrow collection.

2. Invert several times to mix bone marrow.

 

Acceptable

Specimen Type: Blood

Container/Tube:

Preferred: Yellow top (ACD)

Acceptable: Green top (heparin) or lavender top (EDTA)

Specimen Volume: 6 mL

Collection Instructions: Invert several times to mix blood.

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

Blood: 2 mL

Bone Marrow: 1 mL

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

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

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 Ambient (preferred)
Refrigerated

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

Detecting a neoplastic clone associated with Philadelphia chromosome-like acute lymphoblastic leukemia, particularly when a classic abnormality is not detected with the initial panel

 

An adjunct to conventional chromosome studies in patients with B-cell ALL

 

Evaluating specimens in which standard cytogenetic analysis is unsuccessful

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

This test includes a charge for the probe application, analysis, and professional interpretation of results for 7 probe sets (14 individual fluorescence in situ hybridization [FISH] probes). Additional charges will be incurred for all reflex or additional probe sets performed.

 

The Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) panel includes testing for the following four kinase-activating chromosome rearrangements, as well as for IKZF1 deletion, which often accompanies Ph-like ALL:

1q25 rearrangement, ABL2

5q33 rearrangement, PDGFRB

9p24.1 rearrangement, JAK2

9q34 rearrangement, ABL1

7p-, IKZF1/CEP7

t(Xp22.33;var) or t(Yp11.32;var), CRLF2 rearrangement

t(Xp22.33;var) or t(Yp11.32;var), P2RY8 rearrangement

 

When a CRLF2 rearrangement is identified, reflex testing will be performed using the CRLF2/IGH fusion probe set to identify a potential t(X;14)(p22.33;q32) or t(Y;14)(p11.32;q32) cryptic translocation.

 

See B-Lymphoblastic Leukemia/Lymphoma Algorithm in Special Instructions.

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

In the United States the incidence of acute lymphoblastic leukemia (ALL) is roughly 6000 new cases per year (as of 2019). ALL accounts for approximately 70% of all childhood leukemia cases (ages 0-19 years), making it the most common type of childhood cancer. Approximately 85% of pediatric cases of ALL are of B-cell lineage (B-ALL) and 15% are of T-cell lineage (T-ALL). It has a peak incidence at 2 to 5 years of age. The incidence decreases with increasing age, before increasing again at around 50 years of age. ALL is slightly more common in males than females. There is an increased incidence of ALL in individuals with Down syndrome, Fanconi anemia, Bloom syndrome, ataxia telangiectasia, X-linked agammaglobulinemia, and severe combined immunodeficiency. The overall cure rate for ALL in children is about 90% and about 45% to 60% of adults have long-term disease-free survival. CRLF2/IGH rearrangements are more commonly observed in patients with Down syndrome or of Hispanic descent.

 

Specific genetic abnormalities are identified in the majority of cases of B-ALL, either by conventional chromosome studies or fluorescence in situ hybridization (FISH) studies. Each of the B-ALL genetic subgroups are important to detect and can be critical prognostic markers. The decision for early transplantation may be made if t(9;22)(q34;q11.2), MLL (KMT2A) translocations, RUNX1 duplication/amplification (iAMP21) or a hypodiploid clone is identified. In contrast, if ETV6/RUNX1 fusion is detected by FISH or hyperdiploidy is identified by chromosome studies, the patient has a favorable prognosis and transplantation is rarely considered.

 

A newly recognized World Health Organization entity BCR-ABL1-like ALL, also known as Philadelphia chromosome-like acute lymphoblastic leukemia, is increasing in importance due to the poor prognosis seen in pediatric, adolescent, and young adult and adolescent ALL. Common features of this entity involve rearrangements with tyrosine kinase genes involving the following genes: ABL2, PDGFRB, JAK2, ABL1, CRLF2, and P2RY8. Deletion of IKZF1 often accompanies this entity. Some patients who have failed conventional therapies have demonstrated favorable responses to targeted therapies on clinical trials when rearrangements involving these specific gene regions have been identified.

 

Per National Comprehensive Cancer Network guidelines, a combination of cytogenetic and fluorescence in situ hybridization testing is currently recommended in all pediatric and adult patients with B-ALL/lymphoblastic lymphoma (LBL).

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

A neoplastic clone is detected when the percent of cells with an abnormality exceeds the normal reference range for any given probe.

 

The absence of an abnormal clone does not rule out the presence of a neoplastic disorder.

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

This test is not approved by the US Food and Drug Administration, and it is best used as an adjunct to existing clinical and pathologic information.

 

Fluorescence in situ hybridization (FISH) is not a substitute for conventional chromosome studies because the latter detects many chromosome abnormalities associated with other hematological disorders that would be missed by this FISH panel test.

 

Bone marrow is the preferred specimen type for this FISH test. If bone marrow is not available, a blood specimen may be used if there are malignant cells in the blood specimen (as verified by a hematopathologist).

Supportive Data

Each probe was independently tested and verified on unstimulated peripheral blood and bone marrow specimens. Normal cutoffs were calculated based on the results of 25 normal specimens. Each probe set was evaluated to confirm the probe set detected the abnormality it was designed to detect.

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

1. Moorman AV, Harrison CJ, Buck GA, et al: Karyotype is an independent prognostic factor in adult acute lymphoblastic leukemia (ALL): analysis of cytogenetic data from patients treated on the Medical Research Council (MRC) UKALLXII/Eastern Cooperative Oncology Group (ECOG) 2993 trial. Blood. 2007 Apr 15;109(8):3189-3197

2. Moorman AV: The clinical relevance of chromosomal and genetic abnormalities in B-cell precursor acute lymphoblastic leukemia. Blood. Rev. 2012;26:123-135

3. Roberts KG, Li Y, Payne-Turner D, et al: Targetable kinase-activating lesions in Ph-like acute lymphoblastic leukemia. N Engl J Med. 2014 Sept;371(11):1005-1015

4. Mullighan CG: The genomic landscape of acute lymphoblastic leukemia in children and young adults. Hematology Am Soc Hematol Educ Program. 2014 Dec 5;2014(1):174-180

5. Arber DA, Orazi A, Hasserjian R, et al: The 2016 revision to the World Health Organization classification of myeloid neoplasms and acute leukemia. Blood. 2016 May 19;127(20):2391-2405

Special Instructions
Library of PDFs including pertinent information and forms related to the test

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

This test is performed using commercially available and laboratory-developed probes. Deletion of IKZF1 on chromosome 7 is detected using enumeration strategy probes. Rearrangements involving ABL2, PDGFRB, JAK2, ABL1, CRLF2, and P2RY8 are detected using a dual-color break-apart (BAP) strategy probe. A dual-color, dual-fusion fluorescence in situ hybridization (D-FISH) strategy probe set is used to detect t(X/Y;14). For enumeration and BAP strategy probe sets, 100 interphase nuclei are scored; 200 interphase nuclei are scored when D-FISH probes are used. Results are expressed as the percent abnormal nuclei.(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

4 weeks

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

Rochester

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 Regional Manager. 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. This test 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.

88271x14, 88275x7, 88291 x1-FISH Probe, Analysis, Interpretation; 7 probe sets

88271x2, 88275x1-FISH Probe, Analysis; each additional probe set (if appropriate)

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