Hematologic Disorders, Leukemia/Lymphoma; Flow Hold Varies
Evaluating lymphocytoses of undetermined etiology
Identifying B- and T-cell lymphoproliferative disorders involving blood and bone marrow
Distinguishing acute lymphoblastic leukemia (ALL) from acute myeloid leukemia (AML)
Immunologic subtyping of ALL
Distinguishing reactive lymphocytes and lymphoid hyperplasia from malignant lymphoma
Distinguishing between malignant lymphoma and acute leukemia
Phenotypic subclassification of B- and T-cell chronic lymphoproliferative disorders, including chronic lymphocytic leukemia, mantle cell lymphoma, and hairy cell leukemia
Recognizing AML with minimal morphologic or cytochemical evidence of differentiation
Recognizing monoclonal plasma cells
Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.
This test is designed to delay the start of leukemia/lymphoma immunophenotyping until the preliminary assessment is completed. Specimens are held in the laboratory until noon (12 p.m. CST) 2 days after the collection date. For testing to be cancelled, the client must call Mayo Medical Laboratories at 800-533-1710. The testing process will be initiated and fully charged if no notification is received within this time period. To expedite the beginning of testing, please call Mayo Medical Laboratories at 800-533-1710.
The testing process begins with a screening panel. The screening panel will be charged based on the number of markers tested (FIRST for first marker, ADD1 for each additional marker). The interpretation will be based on markers tested in increments of 2 to 8, 9 to 15, or 16 and greater. In addition, reflex testing may occur to fully characterize a disease state or clarify any abnormalities from the screening test. Reflex tests will be performed at an additional charge for each marker tested (FIRST if applicable, ADD1 if applicable).
The triage panel is initially performed on peripheral blood, bone marrow, and fluid samples to evaluate for monotypic B cells by kappa and lambda light chain expression, increased numbers of blasts by CD34 and CD45 expression along with side scatter gating, and increased plasma cells by CD45 expression and side scatter gating. The panel can also evaluate T cells with CD3, CD5, and CD7. Additionally, viability is assessed on all tissue specimens using 7-AAD exclusion. The triage panel also includes antibodies to assess the number of CD3-positive T cells and CD16-positive/CD3-negative natural killer (NK) cells present. This triage panel also determines if there is an increase in the number of T cells that aberrantly coexpress CD16, an immunophenotypic feature of T-cell granular lymphocytic leukemia.
These panels, together with the provided clinical history and morphologic review, are used to determine what, if any, further testing is needed for disease diagnosis or classification. If additional testing is required, it will be added per algorithm to fully characterize a disease state with a charge per unique antibody tested.
If no abnormalities are detected by the initial panel, no further flow cytometric assessment will be performed unless otherwise indicated by specific features of the clinical presentation or prior laboratory results.
Bone marrow specimens being evaluated for possible involvement by a myelodysplastic syndrome (MDS) or a myelodysplastic/myeloproliferative neoplasm (MDS/MPN) including chronic myelomonocytic leukemia (CMML) should be ordered as MYEFL / Myelodysplastic Syndrome by Flow Cytometry, Bone Marrow, not this test.
In addition to reflexing flow cytometric panels, FISH or molecular testing may be recommended by the Mayo pathologist to facilitate diagnosis. They will contact the referring physician or pathologist to confirm the addition of these tests.
Cytogenetic FISH studies
-CCND1/IGH translocation t(11;14), to exclude mantle cell lymphoma in cases of CD5+CD23- B-cell lymphoproliferative disorder.
-PML-RARA translocation t(15;17), to exclude acute promyelocytic leukemia if there is morphologic suspicion and/or blasts and promyelocytes are CD34 and HLA-DR-negative.
-TCL-1 break-apart at 14q32, to exclude T-cell prolymphocytic leukemia in cases with CD4-positive T-cell lymphoproliferative disorder (phenotypic aberrancy or very tight CD4+ population with high CD4:CD8 ratio).
-MYC break-apart at 8q24, with or without IGH-BCL2 t(14;18) and BCL6 break-apart at 3q27, for suspected high grade B-cell lymphomas, based on morphologic assessment and immunophenotype (usually CD10-positive).
Molecular genetic studies:
-T-cell receptor gene rearrangement to examine clonality of T cells in cases showing phenotypically aberrant T-cell population.
Confirmatory cytochemical stains are performed as needed.
The following algorithms are available in Special Instructions:
-Malignant Lymphoma, Guideline for Bone Marrow Staging Studies
-Acute Promyelocytic Leukemia: Guideline to Diagnosis and Follow-up
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Diagnostic hematopathology has become an increasingly complex subspecialty, particularly with neoplastic disorders of blood and bone marrow. While morphologic assessment of blood smears, bone marrow smears, and tissue sections remains the cornerstone of lymphoma and leukemia diagnosis and classification, immunophenotyping is a very valuable and important complementary tool.
Immunophenotyping hematopoietic specimens can help resolve many differential diagnostic problems posed by the clinical or morphologic features.
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.
When performed, 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.
Report will include a morphologic description, a summary of the procedure, the percent positivity of selected antigens, and an interpretive conclusion based on the correlation of the clinical history with the morphologic features and immunophenotypic results.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Specimens will be initially screened to determine which, if any, of the immunophenotyping panels should be performed.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Hanson CA, Kurtin PJ, Katzman JA, et al: Immunophenotypic analysis of peripheral blood and bone marrow in the staging of B-cell malignant lymphoma. Blood 1999;94:3889-3896
2. Hanson CA: Acute leukemias and myelodysplastic syndromes. In Clinical Laboratory Medicine. Edited by KD McClatchey. Baltimore, MD, Williams and Wilkins, Inc, 1994, pp 939-969
3. Morice WG, Leibson PJ, Tefferi A: Natural killer cells and the syndrome of chronic natural killer cell lymphocytosis. Leuk Lymphoma 2001;41(3-4):277-284
4. Langerak AW, van Den Beemd R, Wolvers-Tettero IL, et al: Molecular and flow cytometric analysis of the Vbeta repertoire for clonality assessment in mature TCR alpha beta T-cell proliferations. Blood 2001;98(1):165-173
5. Hoffman RA, Kung PC, Hansen QP, Goldstein G: Simple and rapid measurement of T-lymphocytes and their subclass in peripheral blood. Proc Natl Acad Sci USA 1980;77:4914-4917
6. Jaffe ES, Cossman J: Immunodiagnosis of lymphoid and mononuclear phagocytic neoplasms. In Manual of Clinical Immunology. Third edition. Edited by NR Rose, H Friedman, JL Fahey JL. ASM Press, 1987, pp 779-790
7. Morice WG, Kimlinger T, Katzmann JA, et al: Flow cytometric assessment of TCR-V-beta expression in the evaluation of peripheral blood involvement by T-cell lymphoproliferative disorders: a comparison with conventional T-cell immunophenotyping and molecular genetic techniques. Am J Clin Pathol 2004;121(3):373-383
8. Stelzer GT, Shultz KE, Loken MR: CD45 gating for routine flow cytometric analysis of bone marrow specimens. Ann NY Acad Sci 1993;677:265-280