Detecting a neoplastic clone associated with the common chromosome abnormalities and classic rearrangements observed in adult patients with T-cell acute lymphoblastic leukemia (T-ALL)
An adjunct to conventional chromosome studies in patients with T-ALL
Evaluating specimens in which standard cytogenetic analysis is unsuccessful
Test Id | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
TALAB | Probe, Each Additional (TALAF) | No, (Bill Only) | No |
This test includes a charge for the probe application, analysis, and professional interpretation of results for 10 probe sets (20 individual fluorescence in situ hybridization [FISH] probes). Additional charges will be incurred for all reflex or additional probe sets performed.
If the patient clinically relapses, a conventional chromosome study is useful to identify cytogenetic changes in the neoplastic clone or the possible emergence of a new therapy-related myeloid clone.
The diagnostic adult T-cell acute lymphoblastic leukemia (T-ALL) FISH panel includes testing for the following abnormalities using the following FISH probes:
9p24.1 rearrangement, JAK2 break-apart
t(9;22) or ABL1 amplification, ABL1/BCR
11q23 rearrangement, MLL (KMT2A) break-apart
1p33 rearrangement, TAL1/STIL
t(5;14), TLX3/BCL11B fusion
7q34 rearrangement, TRB break-apart
14q11.2 rearrangement, TRAD break-apart
t(10;11), MLLT10/PICALM fusion
9q34 rearrangement, ABL1 break-apart
5q32 rearrangement, PDGFRB break-apart
When an MLL (KMT2A) rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of:
t(4;11)(q21;q23) AFF1/MLL
t(6;11)(q27;q23) MLLT4(AFDN)/MLL
t(9;11)(p22;q23) MLLT3/MLL
t(10;11)(p12;q23) MLLT10/MLL
t(11;19)(q23;p13.1) MLL/ELL
t(11;19)(q23;p13.3) MLL/MLLT1
When a TRAD rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of t(10;14)(q24;q11.2) TLX1/TRAD or t(11;14)(p13;q11.2) LMO2/TRAD.
When a TRB rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of t(7;10)(q34;q24) TRB/TLX1 or t(7;11)(q34;p13) TRB/LMO2.
For more information see Acute Leukemias of Ambiguous Lineage Testing Algorithm.
Fluorescence In Situ Hybridization (FISH)
t(9p24.1;var) - JAK2 rearrangement
t(9;22)(q34;q11.2) - BCR/ABL1
ABL1 amplification
MLL or KMT2A (11q23) rearrangement
t(4;11)(q21;q23) - AFF1/MLL or AFF4/MLL
t(6;11)(q27;q23) - MLLT4(AFDN)/MLL or AF6/MLL
t(9;11)(p22;q23) - MLLT3/MLL or AF9/MLL
t(10;11)(p13;q23) - MLLT10/MLL
t(11;19)(q23;p13.3) - MLL/MLLT1 or MLL/ENL
t(11;19)(q23;p13.1) - MLL/ELL
TAL1/STIL (1p33) rearrangement or TAL/SIL
t(5;14)(q35;q32) - TLX3/BCL11B or HOX11L2/BCL11B
T-cell receptor beta (TRB) (7q34) rearrangement
t(7;10)(q34;q24) - TRB/TLX1
t(7;11)(q34;p13) - TRB/LMO2
T-cell receptor alpha/delta (TRAD) (14q11.2) rearrangement
t(10;14)(q24;q11.2) - TLX1/TRAD or HOX11/TRAD
t(11;14)(p13;q11.2) - LMO2/TRAD
t(10;11)(p13;q14) - MLLT10/PICALM or AF10/PICALM
t(9q34;var) - ABL1 rearrangement
t(5q32;var) - PDGFRB rearrangement
This test includes a charge for the probe application, analysis, and professional interpretation of results for 10 probe sets (20 individual fluorescence in situ hybridization [FISH] probes). Additional charges will be incurred for all reflex or additional probe sets performed.
If the patient clinically relapses, a conventional chromosome study is useful to identify cytogenetic changes in the neoplastic clone or the possible emergence of a new therapy-related myeloid clone.
The diagnostic adult T-cell acute lymphoblastic leukemia (T-ALL) FISH panel includes testing for the following abnormalities using the following FISH probes:
9p24.1 rearrangement, JAK2 break-apart
t(9;22) or ABL1 amplification, ABL1/BCR
11q23 rearrangement, MLL (KMT2A) break-apart
1p33 rearrangement, TAL1/STIL
t(5;14), TLX3/BCL11B fusion
7q34 rearrangement, TRB break-apart
14q11.2 rearrangement, TRAD break-apart
t(10;11), MLLT10/PICALM fusion
9q34 rearrangement, ABL1 break-apart
5q32 rearrangement, PDGFRB break-apart
When an MLL (KMT2A) rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of:
t(4;11)(q21;q23) AFF1/MLL
t(6;11)(q27;q23) MLLT4(AFDN)/MLL
t(9;11)(p22;q23) MLLT3/MLL
t(10;11)(p12;q23) MLLT10/MLL
t(11;19)(q23;p13.1) MLL/ELL
t(11;19)(q23;p13.3) MLL/MLLT1
When a TRAD rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of t(10;14)(q24;q11.2) TLX1/TRAD or t(11;14)(p13;q11.2) LMO2/TRAD.
When a TRB rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of t(7;10)(q34;q24) TRB/TLX1 or t(7;11)(q34;p13) TRB/LMO2.
For more information see Acute Leukemias of Ambiguous Lineage Testing Algorithm.
Varies
This test is only performed on specimens from patients with T-cell acute lymphoblastic leukemia (T-ALL) who are 31 years and older.
This test is intended for instances when the entire T- ALL fluorescence in situ hybridization (FISH) panel is needed for an adult patient.
-If this test is ordered on a patient 30 years of age or younger, this test will be canceled and automatically reordered by the laboratory as TALPF / T-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), FISH, Pediatric, Varies.
-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 COGTF / T-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Children's Oncology Group Enrollment Testing, FISH, Varies.
-If BALAF / B-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Adult, FISH, Varies is ordered concurrently with this test, the laboratory may cancel TALAF and automatically reorder as TALMF / T-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Specified FISH, Varies with the following FISH probes: TLX3/BCL11B, break-apart TRB, break-apart TRAD, MLLT10/PICALM, TAL1/STIL. If an abnormality is identified that would result in reflex testing in TALAF, the same reflex testing will be performed in the TALMF. This cancellation is necessary to avoid duplicate testing. Probes for break-apart PDGFRB, break-apart JAK2, CDKN2A/D9Z1, ABL1/BCR, break-apart ABL1, break-apart MLL, TP53/D17Z1 will still be performed as part of the adult B-ALL FISH panel.
If limited T-cell ALL FISH probes are preferred, order TALMF / T-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Specified FISH, Varies.
At follow-up, conventional cytogenetic studies (CHRBM / Chromosome Analysis, Hematologic Disorders, Bone Marrow) and targeted T-ALL FISH probes can be evaluated based on the abnormalities identified in the diagnostic study. Order TALMF / T-Cell Acute Lymphoblastic Leukemia/Lymphoma (ALL), Specified FISH, Varies and request specific probes or abnormalities.
If the patient clinically relapses, a conventional chromosome study is useful to identify cytogenetic changes in the neoplastic clone or the possible emergence of a new therapy-related myeloid clone.
For patients with T-cell lymphoma, order TLPDF / T-Cell Lymphoma, Diagnostic FISH, Varies.
For testing paraffin-embedded tissue samples from patients with T-cell lymphoblastic lymphoma, order TLBLF / T-Lymphoblastic Leukemia/Lymphoma, FISH, Tissue. If a paraffin-embedded tissue sample is submitted for this test, testing will be canceled and TLBLF will be added and performed as the appropriate test.
At diagnosis, conventional cytogenetic studies (CHRBM / Chromosome Analysis, Hematologic Disorders, Bone Marrow) and this fluorescence in situ hybridization (FISH) panel should be performed. If there is limited specimen available, only this test will be performed.
Advise Express Mail or equivalent if not on courier service.
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. If not provided, an appropriate indication for testing may be entered by Mayo Clinic Laboratories.
Question ID | Description | Answers |
---|---|---|
GC071 | Reason for Referral | |
GC072 | Specimen |
Whole blood ACD Bone marrow ACD Whole blood Na Hep Bone marrow Na Hep Whole blood EDTA Bone marrow EDTA |
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: 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.
If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.
Blood: 2 mL
Bone Marrow: 1 mL
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Refrigerated |
Detecting a neoplastic clone associated with the common chromosome abnormalities and classic rearrangements observed in adult patients with T-cell acute lymphoblastic leukemia (T-ALL)
An adjunct to conventional chromosome studies in patients with T-ALL
Evaluating specimens in which standard cytogenetic analysis is unsuccessful
This test includes a charge for the probe application, analysis, and professional interpretation of results for 10 probe sets (20 individual fluorescence in situ hybridization [FISH] probes). Additional charges will be incurred for all reflex or additional probe sets performed.
If the patient clinically relapses, a conventional chromosome study is useful to identify cytogenetic changes in the neoplastic clone or the possible emergence of a new therapy-related myeloid clone.
The diagnostic adult T-cell acute lymphoblastic leukemia (T-ALL) FISH panel includes testing for the following abnormalities using the following FISH probes:
9p24.1 rearrangement, JAK2 break-apart
t(9;22) or ABL1 amplification, ABL1/BCR
11q23 rearrangement, MLL (KMT2A) break-apart
1p33 rearrangement, TAL1/STIL
t(5;14), TLX3/BCL11B fusion
7q34 rearrangement, TRB break-apart
14q11.2 rearrangement, TRAD break-apart
t(10;11), MLLT10/PICALM fusion
9q34 rearrangement, ABL1 break-apart
5q32 rearrangement, PDGFRB break-apart
When an MLL (KMT2A) rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of:
t(4;11)(q21;q23) AFF1/MLL
t(6;11)(q27;q23) MLLT4(AFDN)/MLL
t(9;11)(p22;q23) MLLT3/MLL
t(10;11)(p12;q23) MLLT10/MLL
t(11;19)(q23;p13.1) MLL/ELL
t(11;19)(q23;p13.3) MLL/MLLT1
When a TRAD rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of t(10;14)(q24;q11.2) TLX1/TRAD or t(11;14)(p13;q11.2) LMO2/TRAD.
When a TRB rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of t(7;10)(q34;q24) TRB/TLX1 or t(7;11)(q34;p13) TRB/LMO2.
For more information see Acute Leukemias of Ambiguous Lineage Testing Algorithm.
T-cell acute lymphoblastic leukemia (T-ALL) accounts for approximately 25% of cases of adult lymphoblastic leukemia. Specific genetic abnormalities are identified in most cases of T-ALL, although many of the classic abnormalities are "cryptic" by conventional chromosome studies and must be identified by fluorescence in situ hybridization (FISH) studies. Each of the genetic subgroups is important to detect and can be critical prognostic markers.
A combination of cytogenetic and FISH testing is currently recommended in all pediatric and adult patients to characterize the T-ALL clone for the prognostic genetic subgroups. A summary of the characteristic chromosome abnormalities identified in T-ALL is listed in the following table.
Table. Common Chromosome Abnormalities in T-cell Acute Lymphoblastic Leukemia
Cytogenetic change | Genes involved |
del(1p33) | TAL1/STIL |
t(5;14)(q35;q32) | TLX3/BCL11B |
t(5q32;var) | PDGFRB |
t(10;11)(p12;q14) | MLLT10/PICALM |
Episomal amplification | ABL1 |
t(11q23;var) | MLL(KMT2A) |
t(4;11)(q21;q23) | AFF1/MLL(KMT2A) |
t(6;11)(q27;q23) | MLLT4(AFDN)/MLL(KMT2A) |
t(9;11)(p22;q23) | MLLT3/MLL(KMT2A) |
t(10;11)(p12;q23) | MLLT10)/MLL(KMT2A) |
t(11;19)(q23;p13.1) | MLL(KMT2A)/ELL |
t(11;19)(q23;p13.3) | MLL(KMT2A)/MLLT1 |
t(7q34;var) | TRB |
t(7;10)(q34;q24) | TRB/TLX1 |
t(7;11)(q34;p13) | TRB/LMO2 |
t(14q11.2;var) | TRAD |
t(10;14)(q24;q11.2) | TLX1/TRAD |
t(11;14)(p13;q11.2) | LMO2/TRAD |
t(9p24.1;var) | JAK2 |
t(9q34;var) | ABL1 |
Complex karyotype (> or =4 abnormalities) | |
An interpretive report will be provided.
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 neoplastic disorder.
This test is not approved by the US Food and Drug Administration, and it is best used as an adjunct to clinical and pathologic information.
Fluorescence in situ hybridization (FISH) is not a substitute for conventional chromosome studies because the latter detects chromosome abnormalities associated with other hematological disorders that would go undetected 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 neoplastic cells in the blood specimen (as verified by a hematopathologist).
1. T-lymphoblastic leukaemia/lymphoma. In: Swerdlow SH, Campo E, Harris NL, et al, eds: WHO Classification of Tumours. Vol 2. WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. 4th ed. IARC Press; 2017:209-213
2. Gesk S, Martin-Subero JI, Harder L, et al. Molecular cytogenetic detection of chromosomal breakpoints in T-cell receptor gene loci. Leukemia. 2003;17(4):738-745
3. Chin M, Mugishima H, Takamura M, et al. Hemophagocytic syndrome and hepatosplenic (gamma)(delta) T-cell lymphoma with isochromosome 7q and 8 trisomy. J Pediatr Hematol Oncol. 2004;26(6):375-378
4. Graux C, Cools J, Michaux L, Vandenberghe, P, Hagemeijer A: Cytogenetics and molecular genetics of T-cell acute lymphoblastic leukemia: from thymocyte to lymphoblast. Leukemia 2006;20:1496-1510
5. Cayuela JM, Madani A, Sanhes L, Stern MH, Sigaux F. Multiple tumor-suppressor gene 1 inactivation is the most frequent genetic alteration in T-cell acute lymphoblastic leukemia. Blood. 1996;87:2180-2186
6. Hayette S, Tigaud I, Maguer-Satta V, et al. Recurrent involvement of the MLL gene in adult T-lineage acute lymphoblastic leukemia. Blood. 2002;99:4647-4649
7. Graux C, Cools J, Melotte C, et al. Fusion of NUP214 to ABL1 on amplified episomes in T-cell acute lymphoblastic leukemia. Nat Genet. 2004;36:1084-1089
This test is performed using commercially available and laboratory-developed probes. Rearrangements involving TAL1/STIL, PDGFRB, TRB, JAK2, ABL1, MLL (KMT2A), and TRAD are detected using dual-color break-apart (BAP) strategy probes. Dual-color, dual-fusion fluorescence in situ hybridization (D-FISH) strategy probe sets are used to detect t(5;14), t(9;22), t(10;11), and in reflex testing when rearrangements of MLL, TRB, or TRAD genes are detected. Amplification of the ABL1 (9q34) gene region is detected using a D-FISH probe strategy. For enumeration and BAP strategy probe sets, 100 interphase nuclei are scored; 200 interphase nuclei are scored when D-FISH probes are used. All results are expressed as the percent abnormal nuclei.(Unpublished Mayo method)
Monday through Friday
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.
88271x20, 88275x10, 88291x1-FISH Probe, Analysis, Interpretation; 10 probe sets
88271x2, 88275x1-FISH Probe, Analysis; each additional probe set (if appropriate)
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
TALAF | Adult ALL (T-cell), FISH | In Process |
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.
|
---|---|---|
609558 | Result Summary | 50397-9 |
609559 | Interpretation | 69965-2 |
609560 | Result Table | 93356-4 |
609561 | Result | 62356-1 |
GC071 | Reason for Referral | 42349-1 |
GC072 | Specimen | 31208-2 |
609562 | Source | 31208-2 |
609563 | Method | 85069-3 |
609564 | Additional Information | 48767-8 |
609565 | Disclaimer | 62364-5 |
609566 | Released By | 18771-6 |