Diagnosis and management of patients with gastrointestinal stromal tumors
This test is not useful for assessment of hematologic malignancies or germline alterations.
This test uses targeted next-generation sequencing to evaluate for somatic alterations within the KIT (exon 2, 9, 10, 11, 13, 14, 15, 17, 18) and PDGFRA (exons 12, 14, 15, 18) genes.
This test is performed to evaluate for somatic alterations within solid tumor samples. This test is not intended for use for hematological malignancies. Additionally, this test does not assess for germline alterations within the genes listed.
Test Id | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
SLIRV | Slide Review in MG | No, (Bill Only) | Yes |
When this test is ordered, slide review will always be performed at an additional charge.
Polymerase Chain Reaction (PCR)-Based Next-Generation Sequencing
Gastrointestinal Stromal Tumor
GIST
GST9
GST11
GST12
GST13
GST14
GST17
GST18
Mutation Screening
Oncology panel
Tumor panel
KIT
PDGFRA
Next Gen Sequencing Test
NGS
When this test is ordered, slide review will always be performed at an additional charge.
Varies
For KIT Asp816Val allelic variant analysis in mast cell disease, refer to KITAS / KIT Asp816Val Mutation Analysis, Qualitative PCR, Varies.
Multiple oncology (cancer) gene panels are available. For more information see Oncology Somatic NGS Testing Guide.
Pathology report (final or preliminary) at minimum containing the following information must accompany specimen in order for testing to be performed:
1. Patient name
2. Block number-must be on all blocks, slides and paperwork (can be handwritten on the paperwork)
3. Tissue collection date
4. Source of the tissue
This assay requires at least 20% tumor nuclei.
-Preferred amount of tumor area with sufficient percent tumor nuclei: tissue144 mm(2)
-Minimum amount of tumor area: tissue 36 mm(2).
-These amounts are cumulative over up to 10 unstained slides and must have adequate percent tumor nuclei.
-Tissue fixation: 10% neutral buffered formalin, not decalcified
-For specimen preparation guidance, see Tissue Requirement for Solid Tumor Next-Generation Sequencing in Special Instructions. In this document, the sizes are given as 4mm x 4mm x 10 slides as preferred: approximate/equivalent to 144 mm(2) and the minimum as 3mm x 1mm x 10 slides: approximate/equivalent to 36mm(2).
Preferred:
Specimen Type: Tissue block
Collection Instructions: Submit a formalin-fixed, paraffin-embedded tissue block with acceptable amount of tumor tissue.
Acceptable:
Specimen Type: Tissue slide
Slides: 1 stained and 10 unstained
Collection Instructions: Submit 1 slide stained with hematoxylin and eosin and 10 unstained, nonbaked slides with 5-micron thick sections of the tumor tissue.
Note: The total amount of required tumor nuclei can be obtained by scraping up to 10 slides from the same block.
Specimen Type: Cytology slide (direct smears or ThinPrep)
Slides: 1 to 3 slides
Collection Instructions: Submit 1 to 3 slides stained and cover slipped with a preferred total minimum of 5000 total nucleated cells, minimum of 3000 nucleated cells.
Note: Glass coverslips are preferred; plastic coverslips are acceptable but will result in longer turnaround times.
Additional Information: Cytology slides will not be returned.
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen
See Specimen Required
Specimens that have been decalcified (all methods) | Reject |
Specimens that have not been formalin-fixed, paraffin-embedded | Reject |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Frozen | |||
Refrigerated |
Diagnosis and management of patients with gastrointestinal stromal tumors
This test is not useful for assessment of hematologic malignancies or germline alterations.
This test uses targeted next-generation sequencing to evaluate for somatic alterations within the KIT (exon 2, 9, 10, 11, 13, 14, 15, 17, 18) and PDGFRA (exons 12, 14, 15, 18) genes.
This test is performed to evaluate for somatic alterations within solid tumor samples. This test is not intended for use for hematological malignancies. Additionally, this test does not assess for germline alterations within the genes listed.
When this test is ordered, slide review will always be performed at an additional charge.
Targeted cancer therapies are defined as antibody or small molecule drugs that block the growth and spread of cancer by interfering with specific cell molecules involved in tumor growth and progression. Multiple targeted therapies have been approved by the Food and Drug Administration (FDA) for treatment of specific cancers. Molecular genetic profiling is often needed to identify targets amenable to targeted therapies and to minimize treatment costs and therapy-associated risks.
Next-generation sequencing has recently emerged as an accurate, cost-effective method to identify alterations 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 variations 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.
An interpretative report will be provided.
An interpretive report will be provided.
This test cannot differentiate between somatic and germline alterations. Additional testing may be necessary to clarify the significance of results if there is a potential hereditary risk. DNA variants of uncertain significance may be identified.
A negative (wild-type) result does not rule out the presence of an alteration that may be present but below the limits of detection of this assay (approximately 5%-10%). This test does not detect large single or multi-exon deletions or duplications or genomic copy number variants.
Rare alterations may be present that could lead to false-negative or false-positive results. Test results should be interpreted in the context of clinical findings, tumor sampling and other laboratory data. If results obtained do not match other clinical or laboratory findings, contact the laboratory for updated interpretation. Misinterpretation of results may occur if the information provided is inaccurate or incomplete.
Reliable results are dependent on adequate specimen collection and processing. This test has been validated on formalin-fixed, paraffin-embedded tissues; other types of fixatives are discouraged. Improper treatment of tissues, such as decalcification, may cause polymerase chain reaction (PCR) failure.
KIT variations can be seen in neoplasms other than gastrointestinal stromal tumors including, but not limited to: mast cell disease, melanoma, seminomas, acute myeloid leukemia, myeloproliferative neoplasms, and some lymphomas.
PDGFRA variations may be occasionally found in inflammatory fibroid polyps.(1)
We studied a set of 75 formalin-fixed, paraffin-embedded specimens: 40 classic gastrointestinal stromal tumors (GIST), 10 unrelated tumors, 21 neuroendocrine tumors, and 4 other tumors (2 metastatic melanomas, 1 breast cancer, and 1 squamous cell carcinoma). The literature reports that approximately 80% of GIST harbor a alterations in KIT gene, while 2% to 5% harbor alterations in PDGFRA. Overall, we found 83% of GIST tested demonstrated alternations in KIT or PDGFRA, which is in accordance with the literature.
1. Schildhaus HU, Cavlar T, Binot E, et al: Inflammatory fibroid polyps harbour mutations in the platelet-derived growth factor receptor alpha (PDGFRA) gene. J Pathol. 2008;216(2):176-182
2. Robson ME, Blogowski E, Sommer G, et al: Pleomorphic characteristics of a germ-line KIT mutation in a large kindred with gastrointestinal stromal tumors, hyperpigmentation, and dysphagia. Clin Cancer Res. 2004;10:1250-1254
3. Li FP, Fletcher JA, Heinrich MC, et al: Familial gastrointestinal stromal tumor syndrome: phenotypic and molecular features in a kindred. J Clin Oncol. 2005;23:2735-2743
4. Corless CL, Fletcher JA, Heinrich MC: Biology of gastrointestinal stromal tumors. J Clin Oncol. 2004;22:3813-3825
5. Debiec-Rychter M, Raf Sciot R, Le Cesne A, et al: KIT mutations and dose selection for imatinib in patients with advanced gastrointestinal stromal tumors. Eur J Cancer. 2006;42:1093-1103
6. Heinrich MC, Corless CL, Demetri GD, et al: Kinase mutations and imatinib mesylate response in patients with metastatic gastrointestinal stromal tumor. J Clin Oncol. 2003;21:4342-4349
7. Debiec-Rychter M, Dumez H, Judson I, et al: Use of c-KIT/PDGFRA mutational analysis to predict the clinical response to imatinib in patients with advanced gastrointestinal stromal tumors entered on phase I and II studies of the EORTC Soft Tissue and Bone Sarcoma Group. Eur J Cancer. 2004;40:689-695
8. El-Menyar A, Mekkodathil A, Al-Thani H. Diagnosis and management of gastrointestinal stromal tumors: An up-to-date literature review. J Can Res Ther. 2017;13:889-900
Next-generation sequencing is performed to test for the presence of an alternation in targeted regions of the KIT and PDGFRA genes.(Unpublished Mayo method)
Monday through Friday
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 US Food and Drug Administration.
81272-KIT (v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog) (eg, gastrointestinal stromal tumor [GIST], acute myeloid leukemia, melanoma), gene analysis, targeted sequence analysis (eg, exons 8, 11, 13, 17, 18)
81314-PDGFRA (platelet-derived growth factor receptor alpha polypeptide) (eg, gastrointestinal stromal tumor [GIST]), gene analysis, targeted sequence analysis (eg, exons 12, 18)
88381-Microdissection, manual
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
GISTP | GIST Panel, Tumor | In Process |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
54862 | Result | 82939-0 |
54863 | Result Summary | 50397-9 |
54864 | Interpretation | 69047-9 |
54865 | Additional Information | 48767-8 |
54867 | Specimen | 31208-2 |
54868 | Source | 31208-2 |
54869 | Tissue ID | 80398-1 |
54870 | Released By | 18771-6 |