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Test ID: FGFRF FGFR1 (8p11.2) Rearrangement, FISH

Useful For

An aid in identifying patients with myeloproliferative syndromes and the t(8;var)(p11.2;var) translocation who therefore are likely resistant to current chemotherapies

Reflex Tests

Test ID Reporting Name Available Separately Always Performed
_PBCT Probe, +2 No, (Bill Only) No
_PADD Probe, +1 No, (Bill Only) No
_PB02 Probe, +2 No, (Bill Only) No
_PB03 Probe, +3 No, (Bill Only) No
_IL25 Interphases, <25 No, (Bill Only) No
_I099 Interphases, 25-99 No, (Bill Only) No
_I300 Interphases, >=100 No, (Bill Only) No

Testing Algorithm

This test includes a charge for application of the first probe set (2 FISH probes) and professional interpretation of results. Additional charges will be incurred for all reflex probes performed. Analysis charges will be incurred based on the number of cells analyzed per probe set. If no cells are available for analysis, no analysis charges will be incurred.

Method Name

Fluorescence In Situ Hybridization (FISH)

Reporting Name

FGFR1 (8p11.2), FISH

Specimen Type


Shipping Instructions

Advise Express Mail or equivalent if not on courier service.

Necessary Information

A reason for referral and pathology report are required in order for testing to be performed. Send information with specimen. Acceptable pathology reports include working drafts, preliminary pathology or surgical pathology reports.

Specimen Required

Submit only 1 of the following specimens:


Specimen Type: Blood

Container/Tube: Green top (sodium heparin)

Specimen Volume: 7-10 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Other anticoagulants are not recommended and are harmful to the viability of the cells.


Specimen Type: Bone marrow

Container/Tube: Green top (sodium heparin)

Specimen Volume: 1-2 mL

Collection Instructions:

1. Invert several times to mix bone marrow.

2. Other anticoagulants are not recommended and are harmful to the viability of the cells.

Specimen Minimum Volume

Blood: 2 mL
Bone Marrow: 1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Varies Ambient (preferred)

Clinical Information

The gene for fibroblast growth factor receptor 1 (FGFR1) is located at 8p11.2 and rearrangements of FGFR1 are found in stem cell myeloproliferative disorders involving both lymphoid and myeloid lineages. The stem cell myeloproliferative disorders with FGFR1 rearrangements are also called 8p11 (eight p11) myeloproliferative syndromes (EMS) and have variable presentations. EMS often transform rapidly into myelomonocytic leukemia and generally have a poor outcome due to resistance to current chemotherapies, including imatinib myesylate; median survival is about 12 months.


All translocations affecting FGFR1 have a similar structure with a 5' gene partner translocating to the 3' FGFR1 at exon 9. The fusion transcripts encode large proteins containing the N-terminus of the translocation partner, and the tyrosine kinase domain of FGFR1 in the C-terminus. Leukemogenesis is caused by inappropriate activation of FGFR1.

Reference Values

An interpretive report will be provided.


A neoplastic clone is detected when the percent of cells with an abnormality exceeds the normal cutoff for any given probe.


The presence of a positive clone supports a diagnosis of malignancy. 


The absence of an abnormal clone does not rule out the presence of neoplastic disorder.

Clinical Reference

1. Huret JL: FGFR1 (fibroblast growth factor receptor 1). Atlas Genet Cytogenet Oncol Haematol December 2008, Available from URL: Accessed 4/6/2011

2. Patnaik MM, Gangat N, Knudson RA, et al: Chromosome 8p11.2 translocations: prevalence, FISH analysis for FGFR1 and MYST3, and clinicopathologic correlates in a consecutive cohort of 13 cases from a single institution. Am J Hematol 2010;85:238-242

3. WHO Classification of Tumours of Hematopoietic and Lymphoid Tissues. Edited by SH Swerdlow, E Campo, NL Harris, et al. Published by the International Agency for Research on Cancer (IARC), 150 cours Albert Thomas, 69372 Lyon Cedex 08, France, 2008, pp 72-73

Day(s) and Time(s) Performed

Samples processed Monday through Sunday. 

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

Analytic Time

7 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

88271x2, 88291 – DNA probe, each (first probe set), Interpretation and report

88271x2 – DNA probe, each; each additional probe set (if appropriate)

88271x1 – DNA probe, each; coverage for sets containing 3 probes (if appropriate)

88271x2 – DNA probe, each; coverage for sets containing 4 probes (if appropriate)

88271x3 – DNA probe, each; coverage for sets containing 5 probes (if appropriate)

88274 w/modifier 52 – Interphase in situ hybridization, <25 cells, each probe set (if appropriate)

88274 – Interphase in situ hybridization, 25 to 99 cells, each probe set (if appropriate)     

88275 – Interphase in situ hybridization, 100 to 300 cells, each probe set (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
FGFRF FGFR1 (8p11.2), FISH 78915-6


Result ID Test Result Name Result LOINC Value
51804 Result Summary 50397-9
51806 Interpretation 69965-2
51805 Result Table 93356-4
54531 Result 62356-1
CG657 Reason for Referral 42349-1
CG658 Specimen 31208-2
51807 Source 31208-2
51809 Method 49549-9
53429 Additional Information 48767-8
55275 Disclaimer 62364-5
51810 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: