Test Code BALLM B-Cell Lymphoblastic Leukemia Monitoring, Minimal Residual Disease Detection, Flow Cytometry, Varies
Additional Testing Requirements
If cytogenetic tests are also desired an additional specimen should be submitted. It is important that the specimen be obtained, processed, and transported according to instructions for the other required test.
Shipping Instructions
Specimens must be received within 3 days of collection.
Necessary Information
A copy of the diagnostic flow cytometry report is required.
Specimen Required
Submit only 1 of the following specimens:
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Specimen Type: Whole blood
Container/Tube:
Preferred: Yellow top (ACD solution A or B)
Acceptable: Lavender top (EDTA), green top (sodium heparin)
Specimen Volume: 6 mL
Slides: If possible, include 5 to 10 unstained blood smears labeled with 2 unique identifiers
Collection Instructions:
1. Send whole blood specimen in original tube. Do not aliquot.
2. Label specimen as blood.
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Specimen Type: Bone marrow
Container/Tube:
Preferred: Yellow top (ACD solution A or B)
Acceptable: Lavender top (EDTA), green top (sodium heparin)
Specimen Volume: 6 mL
Slides: If possible, include 5 to 10 unstained bone marrow aspirate smears labeled with 2 unique identifiers
Collection Instructions:
1. Submission of bilateral specimens is not required.
2. Send bone marrow specimen in original tube. Do not aliquot.
3. Label specimen as bone marrow.
Useful For
Aids in monitoring a previously confirmed diagnosis of B-cell acute lymphoblastic leukemia
Testing Algorithm
For more information see Acute Leukemias of Ambiguous Lineage Testing Algorithm
Special Instructions
Method Name
Immunophenotyping
Reporting Name
B-ALL Monitoring, MRD Detection, VSpecimen Type
VariesSpecimen Minimum Volume
Blood: 2 mL
Bone Marrow: 1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient | 72 hours |
Reject Due To
Gross hemolysis | Reject |
Clinical Information
B-cell acute lymphoblastic leukemia (B-ALL) is a neoplasm of precursor cells (lymphoblasts) committed to B-cell lineage. B-ALL is the most common acute leukemia in children and adolescents and can also occur in adults. Patients with B-ALL typically present with a high blast count in the peripheral blood and bone marrow replacement with the disease. The diagnosis of B-ALL is based on a combination of morphologic features showing primarily small blasts with open chromatin and high N:C ratio, and an immunophenotype showing immaturity (CD34 and/or TdT expression) associated with B-cell lineage markers (CD19, CD22, and CD79a).
New therapeutic approaches in B-ALL have been increasingly successful. One of the most important predictors of the disease relapse is the ability to detect minimal residual disease (MRD) in the bone marrow specimens following induction phase of the therapy (day 28). Immunophenotyping studies are necessary as morphologic features are not sufficient to detect MRD. The absence of MRD (at 0.002% sensitivity) is an important prognostic indicator in these patients.
This test may also be used to establish an immunophenotypic fingerprint of tumor cells at diagnosis to monitor MRD in these patients after treatments or allogeneic stem cell transplant.
Reference Values
An interpretive report will be provided.
This test will be processed as a laboratory consultation. An interpretation of the immunophenotypic findings and correlation with the morphologic features will be provided by a hematopathologist for every case.
Interpretation
An interpretive report for the presence or absence of B-cell acute lymphoblastic leukemia (B-ALL) minimal residual disease (MRD) is provided. Patients who have detectable MRD by this assay are considered to have residual/recurrent B-ALL.
Cautions
This test is only appropriate for patients who have a previous confirmed diagnosis of B-cell acute lymphoblastic leukemia. Treatment with antibodies to CD19 may interfere with the ability to detect minimal residual disease.
Method Description
Flow cytometric immunophenotyping (high sensitivity) of bone marrow is performed to evaluate the presence or absence of B lymphoblastic leukemia minimal residual disease using the following antibodies: BALLM Panel: CD10, CD19, CD20, CD22, CD24, CD34, CD38, CD45, CD58, and CD66c.(Cherian S, Miller V, McCullouch V, Dougherty K, Fromm JR, Wood BL. A novel flow cytometric assay for detection of residual disease in patients with B-lymphoblastic leukemia/lymphoma post anti-CD19 therapy. Cytometry B Clin Cytom. 2018;94(1):112-120)
Day(s) Performed
Preanalytical processing: Monday through Saturday
Results reported: Monday through Friday
Report Available
1 to 4 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
88184-Flow cytometry; first cell surface, cytoplasmic or nuclear marker
88185 x 9-Flow cytometry; additional cell surface, cytoplasmic or nuclear marker (each)
88188-Flow Cytometry Interpretation, 9 to 15 Markers
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
BALLM | B-ALL Monitoring, MRD Detection, V | 102084-1 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
CK173 | BALLM Result | No LOINC Needed |
CK174 | Final Diagnosis | 22637-3 |
CK175 | Special Studies | 30954-2 |
CK176 | Microscopic Description | 22635-7 |