Sign in →

Test ID: FGFR2 FGFR2 (10q26.1) Rearrangement, FISH, Tissue

Useful For

Providing prognostic information and guiding treatment for patients with cholangiocarcinomas and other tumor types including bladder, thyroid, oral cavity, and brain

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 does not include a pathology consult. If a pathology consultation is requested, PATHC / Pathology Consultation should be ordered and the appropriate FISH test will be ordered and performed at an additional charge.


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

FGFR2 (10q26.1), FISH, Ts

Specimen Type


Necessary Information

1. A pathology report is required in order for testing to be performed. Acceptable pathology reports include working drafts, preliminary pathology or surgical pathology reports.

2. A reason for testing must be provided. If this information is not provided, an appropriate indication for testing may be entered by Mayo Clinic Laboratories.

Specimen Required

Submit only 1 of the following specimens:


Specimen Type: Tissue

Container/Tube: Formalin-fixed, paraffin-embedded tumor tissue block


Specimen Type: Slides

Specimen Volume: Four consecutive, unstained, 5-micron thick sections placed on positively charged slides and 1 hematoxylin and eosin-stained slide

Specimen Minimum Volume

Two consecutive, unstained, 5- micron- thick sections placed on positively charged slides, and 1 hematoxylin and eosin-stained slide.

Specimen Stability Information

Specimen Type Temperature Time Special Container
Tissue Ambient (preferred)

Clinical Information

Cholangiocarcinoma is a malignancy arising from the biliary tract epithelium. These tumors are often clinically advanced at the time of presentation and the prognosis is very poor with a short overall survival. Treatment is generally limited to surgical resection, which is associated with a high degree of morbidity, and palliative chemotherapy regimens. Therefore, additional treatment options are eagerly sought.


Rearrangement of the FGFR2 gene region has been identified in a subset of cholangiocarcinomas. These rearrangements result in overexpression of FGFR2, which offers the possibility of using targeted FGFR2-inhibitor therapy for treatment. FGFR2 rearrangement has been identified in a number of other cancers including those of the bladder, thyroid, oral cavity, and brain. In the future, it is likely that the presence of FGFR2 rearrangements will be exploited in the treatment of these cancers as well.

Reference Values

An interpretive report will be provided.


A positive result is detected when the percent of cells with an abnormality exceeds the normal cutoff for the probe set.


A positive result suggests rearrangement of the FGFR2 locus and a tumor that may be responsive to targeted FGFR2-inhibitor therapy.


A negative result suggests no rearrangement of the FGFR2 gene region at 10q26.1.

Clinical Reference

1. Mitesh BJ, Champion MD, Egan JB, et al: Integrated Genomic Characterization Reveals Novel, Therapeutically Relevant Drug Targets in FGFR and EGFR Pathways in Sporadic Intrahepatic Cholangiocarcinoma. PLOS Genetics 2014 Feb;10(2):e1004135

2. Graham RP, Barr Fritcher EG, Pestova E, et al: Fibroblast growth factor receptor 2 translocations in intrahepatic cholangiocarcinoma. Hum Pathol 2014 Aug;45(8):1630-1638

3. Arai Y, Totoki Y, Hosoda F, et al: Fibroblast growth factor receptor 2 tyrosine kinase fusions define a unique molecular subtype of cholangiocarcinoma. Hepatology 2014;59:1427-1434

4. Wu YM, Su F, Kalyana-Sundaram S, et al: Identification of targetable FGFR gene fusions in diverse cancers. Cancer Discov June 2013;3(6):636-647

Day(s) and Time(s) Performed

Samples processed Monday through Sunday.

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

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
FGFR2 FGFR2 (10q26.1), FISH, Ts 95784-5


Result ID Test Result Name Result LOINC Value
38094 Result Summary 50397-9
38095 Interpretation 69965-2
38096 Result 62356-1
38097 Reason For Referral 42349-1
38098 Specimen 31208-2
38099 Source 31208-2
38100 Tissue ID 80398-1
38101 Method 49549-9
38102 Additional Information 48767-8
38103 Disclaimer 62364-5
38104 Released By 18771-6

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.


If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.

Analytic Time

7 days
Mayo Clinic Laboratories | Gastroenterology Catalog Additional Information: