KIT D816V Positive Acute Mast Cell Leukemia Associated with Normal Karyotype Acute Myeloid Leukemia

Table 4

Cell molecules expressed in MC from our patient as compared to those usually expressed in the MC from patients with MCL or MML, as schematized by Valent et al. in 2014 [9].

Markers	Normal MC	ISM	SSM	ASM	MCL	MML	This case
CD34 (HPCA-1)	−	−	−	−	−	−	−
CD117 (KIT)	+	+	+	+	+	+	+
Tryptase	+	+	+	+	+	+	NA
CD33 (Siglec-3)	+	+	+	+	+	+	+
CD123 (IL-3RA)	−	−	−	+/−	+/−	−	+
CD2 (LFA-2)	−	+/−	+/−	−/+	−/+	−	−
CD25 (IL-2RA)	−	+	+	+	+	−	+
CD30 (Ki1)	−	−/+	+	+	+	NA	+
FcεRI	+	+	+	+	−/+ (low)	−	+ (low)

HPCA-1, human precursor cell antigen-1; IL-2RA, interleukin-2 receptor alpha chain; IL-3RA, interleukin-3 receptor alpha chain; ISM, indolent systemic mastocytosis; SSM, smoldering SM; ASM, aggressive SM; MCL, mast cell leukemia; MML, myelomastocytic leukemia; NA, not available. +, expressed in MCs in almost all (>90% of) cases; +/−, expressed in a majority of MC in a considerable proportion of cases; −/+, expressed in a minority of MC in a smaller subset of cases; −, not expressed. In a few cases, one of the two markers, either CD2 or CD25, may be expressed in neoplastic MCs in MML.