Test Code BALMF B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Specified FISH, Varies
Ordering Guidance
This test is intended for instances when targeted B-cell acute lymphoblastic leukemia/lymphoma (B-ALL/LBL) fluorescence in situ hybridization (FISH) probes are needed based on specific abnormality or abnormalities identified in the diagnostic sample. The FISH probes must be specified on the request when ordering.
If targeted FISH probes are not included with this test order, test processing will be delayed, and the test may be canceled by the laboratory.
If targeted probes are not included with this test request, the test may be canceled and automatically reordered by the laboratory as 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.
For an adult patient, if the entire B-cell ALL FISH panel is preferred, order BALAF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), FISH, Adult, Varies.
For a pediatric patient, if the entire B-cell ALL FISH panel is preferred, order BALPF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), FISH, Pediatric, Varies.
At diagnosis, both conventional cytogenetic studies (CHRBM / Chromosome Analysis, Hematologic Disorders, Bone Marrow) and either BALAF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), FISH, Adult, Varies or BALPF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), FISH, Pediatric, Varies should be performed.
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.
If this test is ordered and the laboratory is informed that the patient is 30 years of age and under AND is on a Children's Oncology Group (COG) protocol, this test will be canceled and automatically reordered by the laboratory COGBF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Children's Oncology Group Enrollment Testing, FISH, Varies.
For patients with B-cell lymphoma, order BLPMF / B-Cell Lymphoma, Specified FISH, Varies.
For testing paraffin-embedded tissue samples from patients with B-ALL/LBL, order BLBLF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma, FISH, Tissue. If a paraffin-embedded tissue sample is submitted for this test, it will be canceled and BLBLF will be added and performed as the appropriate test.
Shipping Instructions
Advise Express Mail or equivalent if not on courier service.
Necessary Information
1. A list of probes requested for analysis is required. Probes available for this test are listed in the Testing Algorithm section.
2. 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/or interpretation may be compromised or delayed in some instances. If not provided, an appropriate indication for testing may be entered by Mayo Clinic Laboratories.
Specimen Required
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 to 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.
3. Send bone marrow specimen in original tube. Do not aliquot.
Acceptable
Specimen Type: Whole blood
Container/Tube:
Preferred: Yellow top (ACD)
Acceptable: Green top (heparin) or lavender top (EDTA)
Specimen Volume: 6 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
Useful For
Detecting a neoplastic clone associated with recurrent common chromosome abnormalities associated with B-cell acute lymphoblastic leukemia/lymphoma (B-ALL/LBL) and Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) using client specified probes
As an adjunct to conventional chromosome studies in patients with B-ALL/LBL
Evaluating specimens in which chromosome studies are unsuccessful
This test should not be used to screen for residual B-ALL/LBL.
Special Instructions
Method Name
Fluorescence In Situ Hybridization (FISH)
Reporting Name
ALL (B-cell), Specified FISHSpecimen Type
VariesSpecimen Minimum Volume
Whole blood: 2 mL; Bone marrow: 1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Refrigerated |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Clinical Information
In the United States, the incidence of B-lymphoblastic leukemia/lymphoma (B-ALL/LBL) is roughly 6000 new cases per year or approximately 1 in 50,000. B-ALL/LBL accounts for approximately 70% of all childhood leukemia cases (ages 0 to 19 years), making it the most common type of childhood cancer. It has a peak incidence at 2 to 5 years of age. This incidence decreases with age before increasing again at around 50 years of age. B-ALL/LBL is slightly more common in male patients than female patients. There is also an increased incidence of B-ALL/LBL in individuals with genetic conditions such as Down syndrome, Fanconi anemia, Bloom syndrome, ataxia telangiectasia, Li-Fraumeni syndrome, X-linked agammaglobulinemia, and severe combined immunodeficiency. The overall cure rate for B-ALL/LBL in children is approximately 90%, and about 45% to 60% of adults have long-term disease-free survival. Of note, CRLF2::IGH fusion is more commonly observed in patients with Down syndrome or of Hispanic descent.
Specific cytogenetic abnormalities are identified in the majority of cases of B-ALL/LBL, by conventional chromosome studies or fluorescence in situ hybridization (FISH) studies. B-ALL genetic subgroups are important to detect and can be critical prognostic markers. For example, a decision for early transplantation may be made if BCR::ABL1 fusion, KMT2A rearrangement, iAMP21, or a hypodiploid clone is identified. In contrast, if the ETV6::RUNX1 fusion or hyperdiploidy is identified, the patient has a more favorable prognosis and transplantation is rarely initially considered.
A newly recognized World Health Organization entity called 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 ALL. Common features of this entity involve rearrangements with tyrosine kinase genes involving the following genes: ABL2, PDGFRB, JAK2, ABL1, CRLF2, and P2RY8, as well as deletions involving IKZF1. Patients who have failed conventional therapies have demonstrated favorable responses to targeted therapies when rearrangements involving these specific gene regions have been identified.
Evaluation of the MYC gene region is included in all diagnostic pediatric B-ALL panels to evaluate for Burkitt lymphoma. If a positive result is obtained, additional testing for the BCL2 and BCL6 gene regions may be considered.
Per National Comprehensive Cancer Network guidelines, a combination of cytogenetic and FISH testing is currently recommended in all pediatric and adult patients with B-ALL/lymphoblastic lymphoma (LBL). Additional cytogenetic techniques such as chromosomal microarray (CMAH / Chromosomal Microarray, Hematologic Disorders, Varies) may be helpful to resolve questions related to ploidy (hyperdiploid clone vs doubled hypodiploid clone) or to resolve certain clonal structural rearrangements such as the presence or absence of intra-chromosomal amplification of chromosome 21 (iAMP21). A summary of the characteristic chromosome abnormalities identified in B-ALL is listed in the following table.
Table. Common Chromosome Abnormalities in B-cell Acute Lymphoblastic Leukemia
Leukemia type |
Cytogenetic change |
Typical demographic |
Risk category |
B-acute lymphoblastic leukemia
|
t(12;21)(p13;q22), ETV6::RUNX1 |
Pediatric |
Favorable |
Hyperdiploidy |
Pediatric |
Favorable |
|
t(1;19)(q23;p13.3), PBX1::TCF3 |
Pediatric |
Intermediate to favorable |
|
t(9;22)(q34;q11.2), BCR::ABL1 |
All ages |
Unfavorable |
|
iAMP21, RUNX1 |
Pediatric |
Unfavorable |
|
del(9p), CDKN2A |
All ages |
Unknown |
|
t(11q23;var), MLL rearrangement |
All ages |
Unfavorable |
|
t(4;11)(q21;q23), AFF1::MLL |
All ages |
Unfavorable |
|
t(6;11)(q27;q23), MLLT4(AFDN)::MLL |
All ages |
Unfavorable |
|
t(9;11)(p22;q23), MLLT3::MLL |
All ages |
Unfavorable |
|
t(10;11)(p12;q23), MLLT10::MLL |
All ages |
Unfavorable |
|
t(11;19)(q23;p13.1), MLL::ELL |
All ages |
Unfavorable |
|
t(11;19)(q23;p13.3), MLL::MLLT1 |
All ages |
Unfavorable |
|
t(14q32;var), IGH rearrangement |
All ages |
Variable |
|
t(X;14)(p22;q32)/t(Y;14)(p11;q32), CRLF2::IGH |
Adolescent/ young adult |
Unfavorable |
|
t(Xp22.33;var) or t(Yp11.32;var), CRLF2 rearrangement |
All ages |
Unfavorable |
|
t(Xp22.33;var) or t(Yp11.32;var), P2RY8 rearrangement |
All ages |
Unfavorable |
|
-17/17p-, TP53 |
All ages |
Unfavorable |
|
t(8q24.2;var), MYC rearrangement |
Pediatric/ adolescent/ young adult |
||
Complex karyotype (≥4 abnormalities) |
Adult |
Unfavorable |
|
Low hypodiploidy/near triploidy |
Adult |
Unfavorable |
|
Near-haploid/hypodiploid |
All ages |
Unfavorable |
|
del(7p) IKZF1 |
All ages |
Unfavorable in absence of ERG deletion |
|
Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) |
t(1q25;var), ABL2 rearrangement |
Pediatric/ adolescent/ young adult |
Unfavorable |
t(5q32;var), PDGFRBÂ rearrangement |
|||
t(9p24.1;var), JAK2 rearrangement |
|||
t(9q34;var), ABL1 rearrangement |
|||
t(Xp22.33;var) or t(Yp11.32;var), CRLF2 rearrangement |
|||
t(Xp22.33;var) or t(Yp11.32;var), P2RY8 rearrangement |
Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
Report Available
7 to 10 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
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
88271 x2, 88275 x1, 88291 x1- FISH Probe, Analysis, Interpretation; 1 probe sets
88271 x2, 88275 x1 - FISH Probe, Analysis; each additional probe set (if appropriate)
88271 x1 -FISH Probe; coverage for sets containing 3 probes (if appropriate)
Forms
If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.