MYD88 reflex to CXCR4
Myeloid differentiation primary response 88; myeloid differentiation primary response gene (88); MYD88_L265P; Lymphoplasmacytic Lymphoma; Waldenström Macroglobulinemia; CXCR4; C-X-C chemokine receptor type 4; CD184
- Tech Only CPT
- Tech Pro CPT 81245 reflex to 81479
- PowerPath Code MYD88; add CXCR4 when MYD88 is positive
- Schedule Monday to Friday
- Turn Around Time 2-4 days for MYD88; 7-14 days for reflexed CXCR4
- Disease State Lymphoplasmacytic Lymphoma, Waldenstrom's macroglobulinemia
- Methodology Real-time Polymerase Chain Reaction (qPCR)-based analysis of the L265P mutation in the MYD88 gene; NGS analysis for common CXCR4 mutations.
Organs
Specimen Requirements
Container Type: Lavender top tube (EDTA)
Specimen Type: Bone Marrow; whole blood
Preferred Volume: 5mL Whole Blood; 2 mL Bone Marrow
Minimum Volume: 3 mL Whole Blood; 1 mL Bone Marrow
Formalin-fixed, paraffin-embedded tissue clots or blocks; EDTA decaled clots or blocks
Diagnostic Utility
Activating mutations of MYD88, particularly the Leu265Pro mutation, are frequently identified in Lymphoplasmacytic lymphoma/Waldenström's macroglobulinemia patients and less frequently in marginal zone lymphoma patients. The same mutation is also found in chronic lymphocytic leukemia and the Activated B-cell type Diffuse Large B-cell Lymphomas. Mutations in CXCR4 have been identified in close to 30% of patients with Waldenstrom macroglobulinemia (WM) carrying MYD88_L265P mutation and have been associated with more aggressive disease presentation and thus affect treatment outcome.
Clinical Significance
Mutations in CXCR4 have been identified in close to 30% of patients with Waldenstrom macroglobulinemia (WM) carrying MYD88_L265P mutation and have been associated with intermediate or high bone marrow disease burden and serum IgM level and thus affect treatment outcome. On the contrary CXCR4 wild type patients have more indolent course of the disease.
Storage and Transportation
Refrigerated: 5 days for blood or bone marrow
Ambient (room temperature): 3 days for blood or bone marrow; ambient for clots and tissue blocks
Cause for Rejection
Serum or plasma. Frozen specimens. Clotted whole blood. Severely hemolyzed specimens. Acid decalcification compromises the specimen quality and is not acceptable.
Retention
Whole blood or bone marrow - One week
DNA - Two years
Tissue blocks or clots - 10 years
Comments
Copy of the referring client's requisition form to accompany specimen.
Results of this test must always be interpreted in the context of relevant clinical and pathological data, and should not be used alone for a diagnosis of malignancy.