SYSTEMIC MASTOCYTOSIS

c-KIT p.(Asp816Val) Variant

The c-KIT p.(Asp816Val) variant has been reported in up to 93% of patients with systemic mastocytosis (Garcia-Montero et al. (2006) Blood 108 (7) 2366-2372). This mutation has also been reported in acute myeloid leukaemia, gastrointestinal stromal tumours, testicular carcinoma and ovarian dysgerminomas. c-KIT p.(Asp816Val) variant positive cells have been reported to be resistant to treatment with imatinib mesylate.

c-KIT p.(Asp816Val) variant analysis can therefore be used as a tool in the differential diagnosis of systemic mastocytosis. However, all molecular data MUST be interpreted in combination with clinical and morphologic features.

 The c-KIT p.(Asp816Val) variant is detected using droplet digital PCR which can detect the variant when present at a level of greater than 0.1%.

Laboratory contact: Dr. Caroline Wickham 01392 408248 caroline.wickham@nhs.net

Clinical contact: Dr. Paul Kerr 01392 402917 paul.kerr1@nhs.net