Test Id : FGF1F

This test includes a charge for the probe application, analysis, and professional interpretation of results for 1 probe set (2 individual fluorescence in situ hybridization [FISH] probes). No analysis charges will be incurred if an insufficient number of representative cells are available for analysis.

This test does not include a pathology consultation. If a pathology consultation is requested, order PATHC / Pathology Consultation, and appropriate testing will be added at the discretion of the pathologist and performed at an additional charge.

Multiple oncology (cancer) gene panels are also available. For more information see Hematology, Oncology, and Hereditary Test Selection Guide

Advise Express Mail or equivalent if not on courier service.

1. A pathology report is required for testing to be performed. If not provided, appropriate testing and/or interpretation may be compromised or delayed. Acceptable pathology reports include working drafts, preliminary pathology, or surgical pathology reports.

2. The following information must be included in the report provided.

1. Patient name

2. Block number - must be on all blocks, slides, and paperwork

3. Date of collection

4. Tissue Source

3. 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.

Submit only 1 of the following specimens:

Preferred

Specimen Type: Tissue block

Collection Instructions: Submit a formalin-fixed, paraffin-embedded tumor tissue block. Blocks prepared with alternative fixation methods may be acceptable; provide fixation method used.

Additional Information:

1. Paraffin-embedded specimens can be from any anatomic location (skin, soft tissue, lymph node, etc).

2. Bone specimens that have been decalcified will be attempted for testing, but the success rate is approximately 50%.

Acceptable

Specimen Type: Tissue slides

Slides: 1 Hematoxylin and eosin stained and 4 unstained

Collection Instructions: Submit 1 slide stained with hematoxylin and eosin and 4 consecutive unstained, positively charged, unbaked slides with 5-micron thick sections of the tumor tissue.

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

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

Providing prognostic information and guiding treatment primarily for patients with squamous cell carcinoma of the lung, breast, esophagus, thymus, and other locations

This test includes a charge for the probe application, analysis, and professional interpretation of results for 1 probe set (2 individual fluorescence in situ hybridization [FISH] probes). No analysis charges will be incurred if an insufficient number of representative cells are available for analysis.

Fibroblast growth factor receptor 1 (FGFR1) is a receptor tyrosine kinase.  FGFR1 overexpression or amplification in squamous cell carcinoma is associated with tumor growth. Studies have shown overexpression or amplification of FGFR1 to be sensitive to FGFR1-tyrosine kinase inhibitors, and FGFR1 inhibitors may be a promising therapeutic option. Therefore, patients with FGFR1 amplification may be candidates for FGFR1 tyrosine kinase inhibitor therapies.

An interpretive report will be provided.

FGFR1 will be clinically interpreted as positive or negative.

The FGFR1 locus is reported as amplified (positive) when the FGFR1:D8Z2 ratio is greater than 2.0 or an average of 6 or more copies of the FGFR1 probe are observed per tumor nucleus.

A tumor with an FGFR1:D8Z2 ratio less than or equal to 2.0 and having an average of less than 6 copies of FGFR1 per tumor nucleus is considered negative for amplification of the FGFR1 locus.

A negative result does not exclude the presence of a neoplastic disorder.?

This test is not approved by the US Food and Drug Administration and is best used as an adjunct to existing clinical and pathologic information.

Fixatives other than formalin (eg, Prefer, Bouin's) may not be successful for fluorescence in situ hybridization (FISH) assays. Non-formalin fixed specimens will not be rejected.

Paraffin-embedded tissues that have been decalcified may not be successful for FISH analysis. The success rate of FISH studies on decalcified tissue is approximately 50%.

FISH studies will be attempted if sufficient tumor is present for analysis. If insufficient tissue/tumor is available for testing, the pathologist reviewing the hematoxylin and eosin-stained slide may find it necessary to cancel testing.

If no FISH signals are observed post-hybridization, the case will be released indicating a lack of FISH results.

FISH analysis was performed on 40 paraffin-embedded tissue samples from patients with various tumors. A series of normal control samples were used to generate the normal cutoffs. FGFR1 amplification was detected in 2 of 40 (5%) of samples. Other abnormalities including aneusomy, duplication and deletion of FGFR1 were also identified and may be observed in addition to FGFR1 amplification in tumor samples.

1. Schultheis AM, Bos M, Schmitz K, et al. Fibroblast growth factor receptor 1 (FGFR1) amplification is a potential therapeutic target in small-cell lung cancer. Mod Pathol. 2014;27(2):214-212

2. Heist RS, Mino-Kenudson M, Sequist LV, et al. FGFR1 amplification in squamous cell carcinoma of the lung. J Thorac Oncol. 2012;7(12):1775-1780

3. Weis J, Sos ML, Seidel D, et al. Frequent and focal FGFR1 amplification associates with therapeutically tractable FGFR1 dependency in squamous cell lung cancer. Sci Transl Med. 2010;2(62):62ra93

4. Craddock KJ, Ludkovski O, Sykes J, et al. Prognostic value of fibroblast growth factor receptor 1 gene locus amplification in resected lung squamous cell carcinoma. J Thorac Oncol. 2013;8(11):1371-1377

5. Schildhaus HU, Heukamp LC, Merkelbach-Bruse S, et al. Definition of a fluorescence in-situ hybridization score identifies high- and low-level FGFR1 amplification types in squamous cell lung cancer. Mod Pathol. 2012;25(11):1473-1480

6. Drago JZ, Formisano L, Juric D, et al. FGFR1 amplification mediates endocrine resistance but retains TORC sensitivity in metastatic hormone receptor–positive (HR+) breast cancer. Clinical Cancer Research. 2019;25(21):6443-51

7. Andre F, Bachelot T, Campone M, et al. Targeting FGFR with dovitinib (TKI258): preclinical and clinical data in breast cancer. Clin Cancer Res. 2013;19(13):3693-702

This test is performed using a commercially available FGFR1 probe set with a FGFR1 probe and a chromosome 8 centromere probe (D8Z2). The selection of tissue and the identification of target areas on the hematoxylin and eosin (H and E)-stained slide are performed by a pathologist. Using the H and E-stained slide as a reference, target areas are etched with a diamond-tipped engraving tool on the back of the unstained slide to be assayed. The probe set is hybridized to the appropriate target areas, and 2 technologists each independently analyze 30 interphase nuclei (60 total) with the results expressed as a ratio of FGFR1:D8Z2 signals.(Unpublished Mayo method)

Monday through Friday

• Authorized users can sign in to Test Prices for detailed fee information.
• Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
• Prospective clients should contact their account representative. For assistance, contact Customer Service.

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

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)