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HelpTest Code CHFXH Chromosome Analysis, Hematologic Disorders, Fixed Cells
Reporting Name
Chromosomes, Hematol Fixed CellsUseful For
Assisting in the diagnosis and classification of certain malignant hematological disorders in fixed cells
Evaluating the prognosis of patients with certain malignant hematologic disorders
Monitoring effects of treatment
Monitoring patients in remission
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| _ML20 | Metaphases, 1-19 | No, (Bill Only) | No |
| _M25 | Metaphases, 20-25 | No, (Bill Only) | No |
| _MG25 | Metaphases, >25 | No, (Bill Only) | No |
| _STAC | Ag-Nor/CBL Stain | No, (Bill Only) | No |
Testing Algorithm
This test only includes a charge for professional interpretation of results and does not include charges for analysis.
Analysis charges will be incurred for total work performed, and generally include 2 banded karyograms and the analysis of 20 or more metaphase cells for this test. If no metaphase cells are available for analysis, no analysis charges will be incurred. If additional analysis work is required, additional charges may be incurred. See the Method Description for specific details.
For more information see:
-Acute Promyelocytic Leukemia: Guideline to Diagnosis and Follow-up
-Bone Marrow Staging for Known or Suspected Malignant Lymphoma Algorithm
-Multiple Myeloma: Laboratory Screening
-Myeloproliferative Neoplasm: A Diagnostic Approach to Bone Marrow Evaluation
Method Name
Chromosome Analysis
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
VariesNecessary Information
A pathology and/or flow cytometry report may be requested by the Genomics Laboratory to optimize testing and aid in interpretation of results.
Provide a reason for testing and specimen type with each specimen. The laboratory will not reject testing if this information is not provided, but appropriate testing and interpretation may be compromised or delayed.
Specimen Required
Specimen Volume: 2 mL
Additional Information: Advise Express Mail or equivalent if not on courier service.
Specimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Ambient (preferred) | ||
| Refrigerated | |||
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Special Instructions
Reference Values
An interpretative report will be provided.
Day(s) Performed
Monday through Friday
CPT Code Information
88291- Interpretation and report
88264 w/ modifier 52-Chromosome analysis with less than 20 cells (if appropriate)
88264-Chromosome analysis with 20 to 25 cells (if appropriate)
88264, 88285-Chromosome analysis with greater than 25 cells (if appropriate)
88283-Additional specialized banding technique (if appropriate)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| CHFXH | Chromosomes, Hematol Fixed Cells | In Process |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 38487 | Result Summary | 50397-9 |
| 38488 | Interpretation | 69965-2 |
| 38489 | Result | 62356-1 |
| 38490 | Reason for Referral | 42349-1 |
| 38491 | Specimen | 31208-2 |
| 38492 | Source | 31208-2 |
| 38493 | Method | 85069-3 |
| 38494 | Banding Method | 62359-5 |
| 38495 | Additional Information | 48767-8 |
| 38496 | Released By | 18771-6 |
Clinical Information
Chromosomal abnormalities play a central role in the pathogenesis, diagnosis, and treatment monitoring of many hematologic disorders. Cytogenetic studies on bone marrow may be helpful in many malignant hematologic disorders as the observation of a chromosomally abnormal clone may be consistent with a neoplastic process.
Certain chromosome abnormalities may help classify a malignancy. As examples, the Philadelphia (Ph) chromosome, also referred to as der(22)t(9;22)(q34;q11.2), is usually indicative of chronic myeloid leukemia (CML) or acute leukemia, t(8;21)(q22;q22) defines a specific subset of patients with acute myeloid leukemia, and t(8;14)(q24.1;q32) is associated with Burkitt lymphoma.
Cytogenetic studies are also used to monitor patients with hematologic neoplasia and may identify disease progression, such as the onset of blast crisis in CML, which is often characterized by trisomy 8, isochromosome 17q, and multiple Ph chromosomes.
Interpretation
To ensure the best interpretation, it is important to provide some clinical information to verify the appropriate type of cytogenetic study is performed.
The following factors are important when interpreting the results:
-Although the presence of an abnormal clone usually indicates a malignant neoplastic process, in rare situations, the clone may reflect a benign condition.
-The absence of an abnormal clone may be the result of specimen collection from a site that is not involved in the neoplasm or may indicate that the disorder is caused by submicroscopic abnormalities that cannot be identified by chromosome analysis.
-On rare occasions, the presence of an abnormality may be associated with a congenital abnormality that is not related to a malignant neoplastic process. Follow-up with a medical genetics consultation is recommended.
-On occasion, bone marrow chromosome studies are unsuccessful. If clinical information has been provided, we may have a FISH study option that could be performed.
Cautions
In some cases, fluorescence in situ hybridization (FISH) studies may detect some disorders better than conventional chromosome studies:
Interfering factors
Technical:
-Not processing the bone marrow as indicated before shipping the specimen
-Not sending the first aspirate from the patient's bone marrow draw
Biological:
-Abnormalities missed due to sampling error
-Subtle structural chromosome abnormalities may be missed occasionally
-Neoplastic cells not dividing
Clinical Reference
1. Swerdlow SH, Campo E, Harris NL, et al. WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. IARC Press; 2017. WHO Classification of Tumours Vol 2
2. Dewald GW, Ketterling RP, Wyatt WA, Stupca PJ. Cytogenetic studies in neoplastic hematologic disorders. In: McClatchey KD, ed. Clinical Laboratory Medicine. 2nd edition. Williams and Wilkens; 2002:658-685
3. Rigolin GM, Cibien F, Martinelli S, et al. Chromosome aberrations detected by conventional karyotyping using novel mitogens in chronic lymphocytic leukemia with "normal" FISH: correlations with clinicobiological parameters. Blood 2012;119(10):2310-2313
Method Description
Metaphase cells are dropped onto microscope slides and are stained by G-banding. Other staining methods are employed as needed. Twenty metaphases are usually examined. If a clone is suspected, but not confirmed within 20 metaphases, 30 metaphases will be analyzed. Minimal evidence for the presence of an abnormal clone is defined as 2 or more metaphases with the same structural abnormality or chromosome gain (trisomy), or 3 or more metaphases lacking the same chromosome. All cells analyzed are captured using a computerized imaging system, and 1 or more karyograms from each clone are prepared to document the type of abnormality and to permit systematic interpretation of the anomalies.(Arsham MS, Barch MJ, Lawce HJ, eds. The AGT Cytogenetics Laboratory Manual. 4th ed. John Wiley and Sons; 2017)