IGH Somatic Hypermutation Analysis, B-Cell Chronic Lymphocytic Leukemia (B-CLL), Varies
Use
Providing prognostic information in patients with newly diagnosed B-cell chronic lymphocytic leukemia. Clonal IGHV gene hypermutation status provides important prognostic information for patients with CLL and small lymphocytic lymphoma (SLL). The presence of IGH SHM is defined as greater than 2% difference from the germline VH gene sequence identity (mutated), whereas less than or equal to 2% difference is considered no SHM (unmutated). The status of SHM has a clear influence on the median survival of CLL patients.
Special Instructions
Both refrigerated and ambient specimens must arrive within 7 days of collection. Collect and package specimen as close to shipping time as possible. Molecular Hematopathology Patient Information is required. Testing may proceed without the patient information; however, it aids in providing a more thorough interpretation. Ordering providers are strongly encouraged to fill out the form and send with the specimen.
Limitations
This test is not intended for use in providing prognostic information for patient with other B-cell neoplasms or hematopoietic tumors. This test requires a minimum monoclonal CLL B-cell percentage in order to amplify the clonal IGH gene rearrangement. This level has been established at 5% of lymphocytes (e.g., as determined by flow cytometric immunophenotyping). A CLL population below 5% will not have a reliable or reproducible clonal gene rearrangement. The prognostic significance of somatic hypermutation (SHM) status is only known when a single functional IGH rearrangement is identified. Rearrangements containing a variation frequency of greater than 2% are interpreted as mutated. Rearrangements containing a variation frequency less than or equal to 2% are interpreted as unmutated.
New York Approved
Methodology
NGS
Biomarkers
LOINC Codes
- 50627-9
- 31208-2
- 50398-7
Result Turnaround Time
14 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
4 mL
Minimum Volume
1 mL
Container
Lavender top (EDTA) or Yellow top (ACD)
Collection Instructions
Invert several times to mix blood. Send whole blood specimen in original tube. Do not aliquot. Label specimen as blood.
Causes for Rejection
Gross hemolysis, Moderately to severely clotted
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 7 days |
| Frozen | Preferred |