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Test ID PHLDF Philadelphia Chromosome-like Acute Lymphoblastic Leukemia (Ph-like ALL), Diagnostic FISH, 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

Submit only 1 of the following specimens:



Specimen Type: Bone marrow


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.



Specimen Type: Blood


Preferred: Yellow top (ACD)

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

Specimen Volume: 6 mL

Collection Instructions: Invert several times to mix blood.

Useful For

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

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.

Method Name

Fluorescence In Situ Hybridization (FISH)

Reporting Name

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

Specimen Type


Specimen Minimum Volume

Blood: 2 mL
Bone Marrow: 1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Varies Ambient (preferred)

Reference Values

An interpretive report will be provided.

Day(s) Performed

Monday through Friday

Report Available

7 to 10 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

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

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

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

LOINC Code Information

Test ID Test Order Name Order LOINC Value
PHLDF Ph-like ALL(B-cell), Diag FISH In Process


Result ID Test Result Name Result LOINC Value
609578 Result Summary 50397-9
609579 Interpretation 69965-2
609580 Result Table 93356-4
609581 Result 62356-1
GC077 Reason for Referral 42349-1
GC078 Specimen 31208-2
609582 Source 31208-2
609583 Method 85069-3
609584 Additional Information 48767-8
609585 Disclaimer 62364-5
609586 Released By 18771-6

NY State Approved



If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.