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Test ID: CHRBM Chromosome Analysis, Hematologic Disorders, Bone Marrow

Useful For

Assisting in the diagnosis and classification of certain malignant hematological disorders


Evaluating the prognosis in 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 includes a charge for cell culture of fresh specimens and professional interpretation of results. Analysis charges will be incurred for total work performed, and generally include 2 banded karyograms and the analysis of 20 metaphase cells. 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.


In addition to the cell culture without mitogens, a CpG-stimulated culture will be added and 10 additional cells will be analyzed for any specimen received from a patient age 30 or older with a reason for testing of chronic lymphocytic leukemia, small lymphocytic leukemia, lymphocytosis, Waldenstrom macroglobulinemia, or when test CLLF / Chronic Lymphocytic Leukemia (CLL), FISH, Varies is ordered concurrently.


The following algorithms are available in Special Instructions:

-Acute Myeloid Leukemia: Testing Algorithm

-Acute Myeloid Leukemia: Relapsed with Previous Remission Testing Algorithm

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

-B-Lymphoblastic Leukemia/Lymphoma Algorithm

-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


If this test is ordered and the laboratory is informed that the patient is on a Children's Oncology Group (COG) protocol, this test will be canceled and automatically reordered by the laboratory as COGBM / Chromosome Analysis, Hematologic Disorders, Children's Oncology Group Enrollment Testing, Bone Marrow.

Method Name

Cell Culture without Mitogens followed by Chromosome Analysis

Reporting Name

Chromosomes, Hematologic, BM

Specimen Type

Bone Marrow

Advisory Information

Chromosome analysis is not recommended for plasma cell neoplasms due to limited clinical utility.(1) If this test and a plasma cell FISH test (PCPDS / Plasma Cell Proliferative Disorder, FISH, Bone Marrow; MSMRT / Mayo Algorithmic Approach for Stratification of Myeloma and Risk-Adapted Therapy Report, Bone Marrow; or MFCF / Myeloma, FISH, Fixed Cells) are ordered concurrently, this test will be cancelled. If a secondary myeloid neoplasm is suspected and both this test and a plasma cell FISH (PCPDS/MSMRT/MFCF) are needed, contact the Cytogenetics Communication Team at 800-533-1710 before sending the specimen.

Shipping Instructions

Advise Express Mail or equivalent if not on courier service.

Necessary Information

1. Provide a reason for testing 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.

2. A pathology and/or flow cytometry report may be requested by the Genomics Laboratory to optimize testing and aid in interpretation of results.

Specimen Required

Container/Tube: Green-top (sodium heparin)

Specimen Volume: 2 to 3 mL

Collection Instructions:

1. It is preferable to send the first aspirate from the bone marrow collection.

2. Invert several times to mix bone marrow.

Specimen Minimum Volume

See Specimen Required

Specimen Stability Information

Specimen Type Temperature Time Special Container
Bone Marrow Ambient (preferred)

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.


Conventional chromosome studies of B-cell disorders are not always successful because B lymphocytes do not proliferate well in cell culture. The agent CpG 7909 (CpG) is a synthetic oligodeoxynucleotide that binds to the Toll-like receptor 9 (TLR9) present on B cells, causing B-cell activation. In the laboratory setting, CpG may be used as a mitogen to stimulate B cells in patient specimens, thus allowing identification of chromosome abnormalities. CpG stimulation reveals an abnormal karyotype in approximately 80% of patients with chronic lymphocytic leukemia, and the karyotype is complex in 20% to 25% of cases. Several studies have reported that increased genetic complexity revealed by CpG-stimulated chromosome studies confers a less favorable time to first treatment, treatment response, and overall survival.

Reference Values

An interpretative report will be provided.


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, there may be a fluorescence in situ hybridization (FISH) study option that could be performed.

Clinical Reference

1. Mellors PW, Binder M, Ketterling RH, et al: Metaphase cytogenetics and plasma cell proliferation index for risk stratification in newly diagnosed multiple myeloma. Blood Adv. 2020 May 26;4(10):2236-2244

2. Dewald GW, Ketterling RP, Wyatt WA, Stupca PJ: Cytogenetic studies in neoplastic hematologic disorders. In: McClatchey KD, ed. Clinical Laboratory Medicine. 2nd ed. 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 Mar 8;119(10):2310-2313

Day(s) and Time(s) Performed

Specimens are processed Monday through Sunday.

Results reported Monday through Friday; 8 a.m.-5 p.m.

Analytic Time

9 days

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

88237, 88291-Tissue culture for neoplastic disorders; bone marrow, blood, 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
CHRBM Chromosomes, Hematologic, BM 81861-7


Result ID Test Result Name Result LOINC Value
52358 Result Summary 50397-9
52360 Interpretation 69965-2
52359 Result 33893-9
CG774 Reason for Referral 42349-1
52361 Specimen 31208-2
52362 Source 31208-2
52364 Method 49549-9
52363 Banding Method 62359-5
54629 Additional Information 48767-8
52365 Released By 18771-6


If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.

Mayo Clinic Laboratories | Hematology Catalog Additional Information:

mml-myeloproliferative-neoplasm, mml-acute-leukemia-myelodysplastic-syndromes, mml-bone-marrow-transplant, mml-lymphoid-disorders, mml-myeloma-amyloidosis-dysprotenemia