Myelomastocytic Leukemia With Aberrant CD25 Expression: Case Report and Review of the Literature

Acute myeloid leukemia with mast cell differentiation is characterized by interstitial mast cells, complex karyotype, <i>TP53</i> alterations and poor prognosis

“…CML in accelerated/blast phase has been reported to develop MML or to have increased immature MCs [2,11]. KIT mutations are observed in approximately 20-40% of core binding factor (CBF) AML cases, but they are typically not detectable in MML as was observed in this cohort [4,8,13,14]. TP53 was the most frequently mutated gene, occurring in about 50% of AML-MC cases, and 64% of the TP53mutated cases had biallelic inactivation (one copy mutated, the other copy lost).…”

“…Our definition of AML-MC is very similar to the "pre-MLL condition" described by Panda et al [11]. MML requires that MCs comprise >10% of BM cells, an arbitrary and stringent cut-off that is likely set too high; as a result only about 10 cases have been reported in the literature [1][2][3][4][5][6][7]. Similar to MLL, the MCs in AML-MC were interstitially distributed in the background of dysplasia.…”

“…myeloid neoplasms with prominent mast cell (MC) differentiation, the latter defined arbitrarily as the presence of atypical MCs and/or metachromatic blasts ≥ 10% on bone marrow (BM) and/or peripheral blood (PB) smears. Cases of mast cell leukemia or systemic mastocytosis associated with hematologic neoplasm are excluded [1][2][3][4][5][6][7][8]. The prognosis of patients with MML is poor [1-3, 9, 10].…”

The First Case of Therapy-Related Myelomastocytic Leukemia Based on the WHO 2008 Classification and the Recently Proposed Diagnostic Criteria

“…Third, MML is associated with poor prognosis [9]. This results partially from a complex karyotype and myelodysplasia, as has been reported here as well as in previous patients with MML [7]. Identification of patients at high risk of developing MML can be the starting point for personalized therapy.…”

“…Differential diagnoses include reactive mast cell (MC) hyperplasia, systemic mastocytosis (SM) with associated clonal hematological non-MC lineage disease, and MC leukemia (MCL) [1]. Myelomastocytic leukemia (MML) is a new classification for AML patients who show an increase in immature and atypical MCs, but who do not fulfill the criteria for MCL or SM [234567]. Here, we describe for the first time a case of therapy-related MML, and review key elements of differential diagnosis in patients with myeloid neoplasms and BM mastocytosis [89].…”