Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Leukemia and Lymphoma Phenotyping AlgorithmClinical Background
Sézary syndrome represents the disseminated leukemic form of the primary cutaneous T-cell lymphoma (CTCL) known as mycosis fungoides (MF).
Epidemiology
- Incidence - <0.5/100,000
- Age - median age of onset in 6th decade
- Sex - M>F
- Ethnicity - occurs more frequently in blacks
Pathophysiology
- Considered to be caused by malignant T-helper cells in dynamic equilibrium between the skin and vascular compartments
Clinical Presentation
- Erythroderma, edema, pruritus, adenopathy, ectropion, keratoderma
- Most commonly, signs and symptoms arise de novo but can follow nonspecific dermatitis or, rarely, MF
- Peripheral blood involvement of circulating malignant lymphoma cells (Sézary cells)
- Patients diagnosed with Sézary syndrome generally have a more advanced disease stage and worse prognosis than those diagnosed with classic MF localized to skin
See Also
Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Leukemia and Lymphoma Phenotyping AlgorithmDiagnosis
Diagnosis
- Indications for testing - abnormal chronic skin rash in patient >50 years old
- Laboratory testing
- CBC with manual differential
- Sézary cells are abnormal lymphocytes which undergo nuclear, but not cytoplasmic, division
- Sézary cells can be seen in small numbers in normal peripheral blood
- Sézary cells >12 µm in diameter and greater than or equal to 20%/100 lymphocytes is diagnostic
- Flow cytometric analysis - phenotyping
- Detect and quantify phenotypically abnormal T-cell population (usually CD4+, CD7-, CD26; see Leukemia Lymphoma Phenotyping algorithm)
- T-cell clonality studies
- Presence of T-cell clone confirms diagnosis of Sézary cell
- CBC with manual differential
- Histology
- Skin biopsy may show no diagnostic features
Differential Diagnosis
- Adult T-cell leukemia
- CLL
- Drug eruption
- Eczema/dermatitis
- Peripheral T-cell lymphoma
Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Leukemia and Lymphoma Phenotyping Algorithm| Tests |
Tests generally appear in the order most useful for common clinical situations
| Test name: CBC with Platelet Count & Automated Differential |
| ARUP #: 0040003 |
| Methodology: Automated Cell Count with Flow Cell Differential |
| Use: Components include: hematocrit, hemoglobin, red blood cell count, white blood cell count, RWD, platelets, MPV, MCV, MCH, MCHC, granulocytes number, granulocytes percentage, eosinophils number, eosinophils percentage, basophil number, basophil percentage, monocytes number, monocytes percentage, lymphocytes number, and lymphocytes percentage |
| Test name: Leukemia/Lymphoma Phenotyping (Comprehensive-Whole Blood) |
| ARUP #: 0096299 |
| Methodology: Flow Cytometry |
| Use: Screen for presence of abnormal T-cells Antigens included: T-cell: CD1, CD2, CD3, CD4, CD5, CD7, CD8, TCR alpha-beta, TCR gamma-delta, Cytoplasmic CD3 |
| Limitations: |
| Test name: T-Cell Clonality Screening Assay by PCR, Fluid |
| ARUP #: 0055567 |
| Methodology: Polymerase Chain Reaction/Fragment Analysis |
| Use: Characterize abnormal T-cells Confirm results from leukemia/lymphoma phenotyping testing |
| Limitations: Results of this test must always be interpreted in the context of morphologic and other relevant data and should not be used alone for a diagnosis of malignancy. This test is not intended to detect minimal residual disease. |
| Test name: Neoplastic Mature T-Cell Evaluation by Flow Cytometry |
| ARUP #: 0093000 |
| Methodology: Flow Cytometry |
| Use: Monitor neoplastic T-cells in patients previously diagnosed with a mature T-cell neoplasm Suggest ordering along with TCR V-Beta flow cytometry test |
| Test name: T-Cell Clonality by Flow Cytometry Analysis of TCR V-Beta |
| ARUP #: 0093199 |
| Methodology: Flow Cytometry |
| Use: Further characterize phenotypically abnormal T-cell populations identified by flow cytometry, and determine whether there is evidence of monoclonality based on expression of T-cell antigen receptor beta chain variable regions (TCR V-Beta) Suggest ordering along with Neoplastic Mature T-Cell Evaluation flow cytometry test |
| Test name: T-Cell Clonality Assessment by Restriction Fragment-Southern Blot Hybridization, Tissue |
| ARUP #: 0055594 |
| Methodology: Restriction Fragment Southern Blot Hybridization |
| Use: Aid in typing of T-cell lymphomas |
| Test name: T-Cell Clonality Assessment by Restriction Fragment-Southern Blot Hybridization, Fluid |
| ARUP #: 0055596 |
| Methodology: Restriction Fragment Southern Blot Hybridization |
| Use: Aid in typing of T-cell lymphomas |
| Test name: Sezary Cell Exam |
| ARUP #: 0049180 |
| Methodology: Stain |
| Use: Diagnose Sézary syndrome in patient with mycosis fungoides (MF) Not a recommended test |
| Test name: Immunohistochemistry Stain Offering |
| ARUP #: arup005 |
| Methodology: Immunohistochemistry |
| Use: For fixed tissue samples, consultative services as well as immunohistochemical staining for kappa, CD4, CD7 and CD26 are available |
Additional Tests Available
| Test name: Leukemia/Lymphoma Phenotyping (Comprehensive - Bone Marrow) |
| ARUP #: 0095244 |
| Methodology: Flow Cytometry |
| Comments: |
| Test name: Leukemia/Lymphoma Phenotyping (Comprehensive - Miscellaneous) |
| ARUP #: 0095243 |
| Methodology: Flow Cytometry |
| Comments: |
References
Guidelines
General References
Medical Reviewers
Bahler, David W., M.D., Ph.D. Medical Director, Hematologic Flow Cytometry, and Acting Medical Director, Molecular Hematopathology at ARUP Laboratories; Associate Professor, Pathology, University of Utah
Perkins, Sherrie L. , M.D., Ph.D. Medical Director, Hematopathology at ARUP Laboratories; Professor, Anatomic Pathology, University of Utah
Comprehensive Review: September 2008
Last Update: September 2008
