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Test ID: HOLDF Hematologic Disorders, Fluorescence In Situ Hybridization (FISH) Hold, Varies

Advisory Information

1. This test is designed to hold blood and bone marrow specimens only.

2.This test does not apply to chromosome analysis. If specimen is to be held for chromosome analysis, order HOLDC / Hematologic Disorders, Chromosome Hold, Varies.

3. Due to stability issues, test PCPDS / Plasma Cell Proliferative Disorder, FISH, Bone Marrow cannot be added onto specimens held under this test.

Shipping Instructions

Advise Express Mail or equivalent if not on courier service.

Necessary Information

Provide a reason for testing with each specimen and bone marrow pathology report (if available). The laboratory will not reject testing if this information is not provided, but appropriate testing and interpretation may be compromised or delayed.

Specimen Required

Submit only 1 of the following specimens:



Specimen Type: Bone marrow

Container/Tube: Green top (sodium heparin)

Specimen Volume: 1 to 2 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 Type: Whole blood

Container/Tube: Green top (sodium heparin)

Specimen Volume: 6 mL

Collection Instructions: Invert several times to mix blood.


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

Useful For

Processing the bone marrow or peripheral blood specimen but delaying fluorescence in situ hybridization (FISH) analysis while preliminary morphologic assessment is in process

Reflex Tests

Test ID Reporting Name Available Separately Always Performed
BALLF ALL (B-cell), FISH Yes No
BLPF B-cell Lymphoma, FISH, B/BM Yes No
CHICF CHIC2 (4q12) Deletion, FISH Yes No
ETVBF ETV6 (12p13.2) Rearrangement, FISH Yes No
FGFRF FGFR1 (8p11.2), FISH Yes No
IMRGF Imatinib Mesylate Resp Genes, FISH Yes No
JAK2F JAK2 (9p24.1) Rearrangement, FISH Yes No
MFCF Myeloma, FISH, Fixed Cells Yes No
MISCF Miscellaneous Studies, FISH Yes No
TALLF ALL (T-cell), FISH Yes No
TLPF T-cell Lymphoma, FISH, B/BM Yes No

Testing Algorithm

This test is designed to hold the sample and delay fluorescence in situ hybridization (FISH) testing while preliminary morphologic assessment or flow cytometry testing is in process.


Hold policy: Upon sample receipt, the specimen will be held in the laboratory. FISH testing will not be performed unless the client contacts the laboratory and indicates that FISH testing is desired. The client must contact the Cytogenetics Laboratory at 800-533-1710 by 4 p.m. (central time) no later than 4 business days (96 hours) after the specimen was collected. If no notification is received by this time, the order will be processed as "cancelled". Weekend communication can be deferred until Monday.

Method Name

Direct Preparation of Specimen

Reporting Name

Heme FISH Hold, B/BM

Specimen Type


Specimen Minimum Volume

Blood: 2 mL
Bone marrow: 1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Varies Ambient (preferred)

Clinical Information

Fluorescence in situ hybridization (FISH) analysis using gene-specific probes is a useful methodology to detect common, recurrent chromosome abnormalities for most hematologic malignancies. Based on morphologic review of the bone marrow or peripheral blood specimen by a hematopathologist, a determination of additional appropriate testing can be made. If the specimen does not show evidence of malignancy, FISH analysis may not be necessary. Depending on the diagnosis, conventional chromosome analysis may also be more informative.

Reference Values

Not applicable


If notified by the client, this test may be canceled and a processing fee will be assessed.


If no notification to proceed with testing is received, this test will be reported as "canceled."

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

4 days

Test Classification

Not Applicable

CPT Code Information

See individual reflex tests

LOINC Code Information

Result ID Test Result Name Result LOINC Value
51836 Result Summary 50397-9
51838 Interpretation 69965-2
CG666 Reason for Referral 42349-1
CG667 Specimen 31208-2
51839 Source 31208-2
CG791 Requested FISH Test 48767-8
51841 Method 49549-9
53433 Additional Information 48767-8
51842 Released by 18771-6
Mayo Clinic Laboratories | Hematology Catalog Additional Information:

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