Detection Of cKit D816V In Various Subtypes Of Mastocytosis

Detection of the D816V mutation in an extracutaneous organ is a minor criterion for the diagnosis of SM (SM

criterion).[3] In the presence of other (i.e., one major or two minor) SM criteria, the final diagnosis SM can be established[3- (Table 1). Patients with cutaneous masto-cytosis (CM) may also exhibit D816V (in their skin or even in BM), but other criteria for SM are not fulfilled.

In the diagnostic workup of suspected SM, analysis for the D816V mutation is routinely performed on BM and PB samples.[3-5,27] However, because SM can involve virtually all organs, the D816V mutation may be detected not only in BM and PB cells but also in other tissues such as the skin, liver, or gastrointestinal tract.[25] For most patients, it is recommended to isolate mononuclear cells (MNCs) from the BM and PB to seek for the c-kit mutation D816V.[3,27] Although c-kit D816V is detectable in BM MNC in the majority of all patients with ISM by RFLP, the organs affected and the distribution of the mutation in various hematopoietic cell lineages vary among patients.[3- In typical ISM, D816V is usually detectable in the BM, but not in unfractionated PB MNCs. By contrast, in smoldering SM, a novel subtype of (I)SM characterized by a high burden of MCs and multilineage involvement, the mutation is detectable in BM MNCs as well in unfractionated PB MNCs.[28-30] In these patients, the mutation appears to be present not only in MCs but also in monocytes and even in B lymphocytes.[26- By contrast, in typical ISM, the D816V mutation is only detectable in samples containing MCs.

In a group of patients with SM, an AHNMD is de-tectable.[3,9] In most cases, a myeloid neoplasm such as a myeloid leukemia or myeloproliferative disorder is found.[3,9- Similar to patients with smoldering SM (which can transform to SM-AHNMD), the c-kit mutation D816V is often detectable in unfractionated PB MNCs in these patients. Especially in patients with an associated chronic myelomonocytic leukemia (CMML), the D816V mutation was found to be expressed in leukemic cells.[24] In patients with an associated AML, leukemic blasts may also

Table 1 WHO classification of mastocytosis and typical patterns of expression of D816V in various organs c-Kit D816V

Table 1 WHO classification of mastocytosis and typical patterns of expression of D816V in various organs c-Kit D816V

Disease variant

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Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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