Next-generation sequencing has recently emerged as an accurate, cost-effective method to identify mutations across numerous genes known to be associated with response or resistance to specific targeted therapies. This test is a single assay that uses formalin-fixed paraffin-embedded tissue to assess for common mutations in the KIT and PDGFRA genes known to be associated with gastrointestinal stromal tumors (GIST). The results of this test can be useful for assessing prognosis and guiding treatment of individuals with GIST.

Rondell P. Graham, M.B.B.S., gives an overview of this test available through Mayo Clinic Laboratories. He discusses when this testing should be ordered, how this testing compares to other testing approaches, and what clinical action can be taken due to the results of this testing.

Testing

Useful for:

Diagnosis and management of patients with gastrointestinal stromal tumors

Specimen Requirements

Preferred:

Specimen Type: Tissue

Container/Tube: Tissue block

Collection Instructions: Submit a formalin-fixed, paraffin-embedded tissue block.

Acceptable:

Specimen Type: Tissue

Container/Tube: Slides

Specimen Volume: 1 stained and 10 unstained

Collection Instructions: Submit 1 slide stained with hematoxylin and eosin and 10 unstained, non-baked slides with 5-micron thick sections of the tumor tissue.

Specimen Type: Cytology

Container/Tube: Cytology slide (Direct smears or ThinPrep)

Specimen Volume: 1 to 2 slides (stained and coverslipped) with a minimum of 5000 total nucleated cells

Collection Instructions: Submit 1 to 2 slides stained and coverslipped

Additional Information: Cytology slides will not be returned.

Performance Information

Day(s) and Time(s) Test Performed 

Monday through Friday; Varies

Analytic Time 

12 days

Alyssa Frank

Alyssa Frank

Alyssa Frank is a Marketing Segment Manager at Mayo Clinic Laboratories. She leads marketing strategies for product management and specialty testing. Alyssa has worked at Mayo Clinic since 2015.