• Test Code:
  • Department:
  • Test Synonyms:
    KIT (cKIT) Mutation Screening for Mastocytosis and Mast Cell Leukemia (exon 17)
  • CPT Code(s):

KIT gene mutations are present in the majority cases of mast cell disease/systemic mastocytosis.1,2

  • Adults
    • D816V mutation is present in 93% of cases3
    • Other mutations are rare (exon 17 D816Y, 815-817 indels; exon 11)
  • Children4
    • D816V mutation is present in 36%
    • Exon 8 in 18% (mostly del 419)(hereditary in some cases)
    • Exon 9 in 20% (ITD 502-503; K509I) (hereditary in some cases)
    • Exon 11 (rare)


DNA is extracted and purified from fresh blood, bone marrow aspirate, paraffin-embedded bone marrow biopsy, clot or other tissue (e.g. skin, GI biopsy).

  • Samples from adult patients are screened for the D816V mutation by real-time allele-specific PCR that includes an internal positive control for DNA quality.
    • Sensitivity: 1% mutant allele
  • Samples from pediatric patients are screened for the D816V mutation by the above assay; negative samples are further screened for mutations in KIT exons 8, 9 & 11 by standard sequencing.
    • Sensitivity (exons 8, 9, 11): 20% mutant allele

Specimen Requirements:

Paraffin blocks or slides:

    • A paraffin block, or
    • 10 unstained sections of tumor (4-5 microns) (15 sections for small biopsies).
    • Due to DNA damage, decalcified specimens are not recommended.

Blood or bone marrow:

    • 2-10 mL Yellow (ACD) or purple (EDTA) tube (unspun)
    • Bone marrow aspirates or cores are acceptable if received in the lab within 24 hours (room temperature) or 4 days (refrigerated; never frozen).
    • Frozen cell pellets of bone marrow-derived leukocytes (without red blood cells) are also acceptable.

Deliver to lab at shipping address above within 24 hours of collection;  if sample cannot arrive within 24 hours, refrigerate until sample can be transported. 

A REQUISITION FORM MUST ACCOMPANY ALL SAMPLES.  Please include detailed clinical information.

Test Performed (Days):

Mon – Fri

Turn Around Time:

7-10 days

Shipment Sensitivity Requirements:

  • Package and ship specimen to remain cool during transit, but not frozen, unless shipping frozen pellets.
  • Ship via overnight express, using the FedEx priority overnight label provided.

 Contact Client Services for shipping kits and instructions at (855) 535-1522.


  1. Tefferi & Pardanani. Systemic mastocytosis: current concepts and treatment advances. Curr Hematol Rep. 3:197-202, 2004.
  2. Pardanani et al. Imatinib for systemic mast-cell disease. Lancet. 362(9383):535-6, 2003.
  3. Garcia-Montero et al. KIT mutation in mast cells and other bone marrow hematopoietic cell lineages in systemic mast cell disorders: a prospective study of the Spanish Network on Mastocytosis (REMA) in a series of 113 patients. Blood. 108:2366-72, 2006.
  4. Bodemer et al. Pediatric mastocytosis is a clonal disease associated with D816V and other activating c-KIT mutations J Inves Dermatol 130:804-815, 2009.

Additional Info:

The Knight Cancer Institute at Oregon Health & Science University is a pioneer in the field of precision cancer medicine. The institute's director, Brian Druker, M.D., helped prove it was possible to shut down just the cells that enable cancer to grow. This breakthrough has made once-fatal forms of the disease manageable and transformed how cancer is treated. The OHSU Knight Cancer Institute is the only National Cancer Institute-designated Cancer Center between Sacramento and Seattle – an honor earned only by the nation's top cancer centers. It is headquarters for one of the National Cancer Institute's largest research collaboratives, SWOG, in addition to offering the latest treatments and technologies as well as hundreds of research studies and clinical trials.

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