TY - JOUR T1 - KIT<sup>D816V+</sup> systemic mastocytosis associated with KIT<sup>D816V+</sup> acute erythroid leukaemia: first case report with molecular evidence for same progenitor cell derivation JF - Journal of Clinical Pathology JO - J Clin Pathol SP - 1147 LP - 1149 DO - 10.1136/jcp.2009.067876 VL - 62 IS - 12 AU - S A McClintock-Treep AU - H-P Horny AU - K Sotlar AU - M K Foucar AU - K K Reichard Y1 - 2009/12/01 UR - http://jcp.bmj.com/content/62/12/1147.abstract N2 - A case of systemic mastocytosis associated with a clonal haematological non-mast cell lineage disease (SM-AHNMD), where the associated disease is acute erythroid leukaemia (erythroid/myeloid type), is reported. Interestingly, molecular studies showed the KITD816V+ mutation not only in the mast cells, but also in the myeloid blast population and the leukaemic erythroid cells. As is the case with most erythroid leukaemias, the patient had a very aggressive clinical course and died shortly after diagnosis. It is believed that this is the first reported case of systemic mastocytosis with erythroid leukaemia where the KITD816V+ mutation was detected in all three cell types. Molecular findings provide evidence for derivation of these seemingly morphologically distinct lesions from the same clonal precursor cell. From a practice standpoint, this case illustrates the importance of definitively diagnosing the associated non-mast cell lineage disease due to its prognostic implications. ER -