TEST CATALOG ORDERING & RESULTS SPECIMEN HANDLING CUSTOMER SERVICE EDUCATION & INSIGHTS
Test Catalog

Test ID: CHFXH    
Chromosome Analysis, Hematologic Disorders, Fixed Cells

Useful For Suggests clinical disorders or settings where the test may be helpful

Assisting in the diagnosis and classification of certain malignant hematological disorders

 

Evaluating the prognosis of patients with certain malignant hematologic disorders

 

Monitoring effects of treatment

 

Monitoring patients in remission

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

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.

 

The following algorithms are available in Special Instructions:

-Acute Promyelocytic Leukemia: Guideline to Diagnosis and Follow-up

-Bone Marrow Staging for Known or Suspected Malignant Lymphoma Algorithm

-Laboratory Screening Tests for Suspected Multiple Myeloma

-Myelodysplastic Syndrome: Guideline to Diagnosis and Follow-up

-Myeloproliferative Neoplasm: A Diagnostic Approach to Bone Marrow Evaluation

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

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.

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.

An interpretative report will be provided.

Interpretation Provides information to assist in interpretation of the test results

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 Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

In some cases, 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 Recommendations for in-depth reading of a clinical nature

1. Dewald GW, Ketterling RP, Wyatt WA, Stupca PJ: Cytogenetic studies in neoplastic hematologic disorders. In Clinical Laboratory Medicine. Second edition. Edited by KD McClatchey. Baltimore, Williams and Wilkens, 2002, pp 658-685

2. 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 Mar 8;119(10):2310-2313

Special Instructions Library of PDFs including pertinent information and forms related to the test