Sign in →

Test Code MISC2MAYOKITE KIT Mutation Exons 8-11 and 17, Hematologic Neoplasms, Sequencing, Varies

Useful For

Prognostic assessment of acute myeloid leukemias with core-binding factor translocations (inv16 or t[16;16] CBFB-MYH11 or t[8;21] RUNX1-RUNX1T1)

 

This test is not intended for KIT evaluation in solid tumors (eg, melanoma, gastrointestinal stromal tumor).

Method Name

Sanger Sequencing

Reporting Name

KIT Mutation, Hematologic Neoplasm

Specimen Type

Varies


Ordering Guidance


This test is intended for detection of KIT mutations in "core-binding factor" (CBF) acute myeloid leukemias (AML). For systemic mastocytosis, order KITVS / KIT Asp816Val Mutation Analysis, Varies.

 

This test is not intended for KIT evaluation in solid tumors (eg, melanoma, gastrointestinal stromal tumor); for these indications, refer to one of the following:

-Gastrointestinal Stromal Tumor (GIST) Targeted Gene Panel, Next-Generation Sequencing, Tumor

-Melanoma Targeted Gene Panel, Next-Generation Sequencing, Tumor

-Solid Tumor-Targeted Cancer Gene Panel, Next-Generation Sequencing, Varies



Shipping Instructions


Specimen must arrive within 7 days of collection.



Necessary Information


The following information is required:

1. Pertinent clinical history

2. Clinical or morphologic suspicion

3. Date and time of collection

4. Specimen source



Specimen Required


Submit only 1 of the following specimens:

 

Specimen Type: Blood

Container/Tube: Lavender top (EDTA) or yellow top (ACD)

Specimen Volume: 3 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send whole blood specimen in original tube. Do not aliquot.

3. Label specimen as blood.

Specimen Stability Information: Ambient (preferred)/Refrigerate

 

Specimen Type: Bone marrow

Container/Tube: Lavender top (EDTA) or yellow top (ACD)

Specimen Volume: 2 mL

Collection Instructions:

1. Invert several times to mix bone marrow.

2. Send bone marrow specimen in original tube. Do not aliquot.

3. Label specimen as bone marrow.

Specimen Stability Information: Ambient (preferred)/Refrigerate

 

Specimen Type: Extracted DNA from blood or bone marrow

Container/Tube: 1.5- to 2-mL tube

Specimen Volume: Entire specimen

Collection Instructions: Label specimen as extracted DNA from blood or bone marrow with an indication of volume and concentration of the DNA.

Specimen Stability Information: Frozen (preferred)/Refrigerate/Ambient

 

Specimen Type: Paraffin-embedded tissue

Container/Tube: Paraffin block

Specimen Volume: Entire block

Additional Information: Tissue must demonstrate involvement by a hematologic neoplasm (eg, acute myeloid leukemia: AML), not solid tumors.

Specimen Stability Information: Ambient

 

Specimen Type: Paraffin-embedded bone marrow aspirate clot

Container/Tube: Paraffin block

Specimen Volume: Entire block

Specimen Stability Information: Ambient

 

Specimen Type: Tissue

Slides: Unstained slides

Specimen Volume: 10 Slides

Additional Information: Tissue must demonstrate involvement by a hematologic neoplasm (eg, AML), not solid tumors.

Specimen Stability Information: Ambient


Specimen Minimum Volume

Blood, bone marrow: 1 mL
Extracted DNA from blood or bone marrow: 50 microliters (mcL) at 20 ng/mcL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Varies Varies 7 days

Reject Due To

Gross hemolysis Reject
Bone marrow core biopsies
Paraffin shavings
Frozen tissues
Moderately to severely clotted
Reject

Clinical Information

Acquired mutations in the KIT gene are identified in a subset of acute myeloid leukemias (AML) characterized by inv16 or t(16;16) CBFB-MYH11 or t(8;21) RUNX1-RUNX1T1 genetic abnormalities (approximately 10%-20% of cases) and in this setting, the additional presence of a KIT gene mutation has been described as an adverse prognostic factor in some studies. KIT mutations in AML tend to involve exons 8 through 11 and 17, although the p.Asp816Val (D816V) variant, which is highly prevalent in systemic mastocytosis (SM), is less common in AML.

 

Mastocytosis is a hematologic disorder characterized by abnormal mast cell expansion in the bone marrow and extramedullary organ sites (eg, skin, gastrointestinal tract). Disease can be localized to skin (ie, cutaneous mastocytosis: CM) or present systemically, with variable features of disease aggressiveness and symptomatology. Variants in the KIT gene are identified in a large majority of patients with both CM and SM. The D816V abnormality is identified in most patients with SM, and this finding represents an important minor diagnostic criterion in the 2008 WHO classification. The D816V is less commonly seen in CM, although single nucleotide variants are present in other KIT exons. Rare cases of familial mastocytosis are also described with KIT mutations involving exons 8 and 9. Although KIT gene mutation represents an important diagnostic marker for SM, the number of bone marrow mast cells is often limited in aspirate samples. Therefore, if SM is clinically and pathologically suspected, KIT testing should first proceed with a sensitive and specific screen for the D816V (KITVS / KIT Asp816Val Mutation Analysis, Varies) prior to consideration of KIT gene sequencing, based on the greatly enhanced sensitivity of the polymerase chain reaction test for this particular variant. In AML, KIT sequencing is preferred, given the wider spectrum of mutations in other KIT exons.

Reference Values

An interpretive report will be provided

Interpretation

Mutations detected or not detected. An interpretive report will be provided.

Method Description

Total DNA is extracted from the sample and exons 8, 9, 10, 11, and 17 of the KIT gene are amplified by polymerase chain reaction followed by Sanger sequencing with evaluation by capillary electrophoresis. Review of the sequence data is performed using a combination of automated calls and manual inspection.(Unpublished Mayo method)

Day(s) Performed

Monday through Friday

Report Available

5 to 8 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

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 US Food and Drug Administration.

CPT Code Information

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)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
KITE KIT Mutation, Hematologic Neoplasm 55201-8

 

Result ID Test Result Name Result LOINC Value
39426 KIT Sequencing Result No LOINC Needed
MP027 Specimen Type 31208-2
37921 Final Diagnosis 50398-7

Forms

1. Hematopathology Patient Information (T676) in Special Instructions

2. If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.

Testing Algorithm

The following algorithms are available:

-Acute Myeloid Leukemia: Testing Algorithm

-Mast Cell Disorder: Diagnostic Algorithm, Bone Marrow

Secondary ID

64589