Acute eosinophilic leukemia: characterization by cytochemistry, chromosomal analysis, and in vitro colony formation

Abstract

A pericentric inversion of chromosome 16 and acute myelomonocytic leukemia [AMMoL, M4 French-American-British (FAB)] with abnormal bone marrow eosinophils has recently been shown to form a new cytogenetic-clinicopathological entity. A patient otherwise undistinguishable from the more typical cases but lacking the FAB criteria for AMMoL is described. In such a situation, in vitro colony formation closely resembling that of acute myoblastic leukemia together with the clinical, morphological, cytochemical, and cytogenetic characteristics reported might serve as an indicator that these patients run an acute course justifying a diagnosis of acute eosinophilic leukemia and immediate institution of aggressive chemotherapy. The importance of the in vitro growth pattern regarding the differential diagnosis of disorders associated with predominant proliferation of eosinophils is discussed.

AML M1 and M2 with Eosinophilia and AML M4Eo: Diagnostic and Clinical Aspects

“…The small number of cases which can be called eosinophilic leukemia distinct from the typical M2 with eosinophilia and M4Eo are characterized by a marked increase in the number of immature eosinophils with more than 10% blast forms in the marrow, infiltration of the tissues with immature cells, and a clinical course similar to other acute leukemias including anemia and thrombocytopenia. 13 Interestingly, in CML blast crisis, cases with the cytological abnormalities of M4Eo and inv ( 16) have been describedl4.15 and this confirms the assumption, that chromosomal changes can determine the cell phenotype even in this situation of transition from chronic to acute phase in CML. The question whether the eosinophils are part of the leukemic process cannot be answered with absolute certainty at the moment.…”