title: Minimally differentiated acute myeloid leukemia (AML-M0): comparison of 25 cases with other French-American-British subtypes.
abstract: We compared the immunophenotypic and karyotypic features of 25 cases of minimally differentiated acute myeloid leukemia (AML-M0) with those of 247 cases comprising all AML French-American-British (FAB) classification. Myeloperoxidase (MPO) was detectable with a specific monoclonal antibody in all cases of AML-M0, whereas CD13 and CD33 were both negative in 4 of the 25 cases. Thus, anti-MPO reliably detects minimal myeloid differentiation in AML-M0. CD34 and terminal deoxynucleotidyl transferase (TdT) were more frequently expressed in AML-M0 (96% and 68% of the cases, respectively) than in the other FAB subsets (P < .001 for both). By contrast, GP-170 and CD7 were less frequently expressed in AML-M0 than in FAB classes such as M1, M4, and M5 (P = .02 and .003, respectively). A total of 80% of AML-M0 cases carried lymphoid markers (including TdT), and 48% showed a coordinate positivity for two or more of them. CD2, CD5, CD10, and CD19 were expressed in a similar fashion among the different FAB groups, whereas CD4 expression was significantly more frequent in AML-M0, AML-M4, and AML-M5 (P = .014). AML-M0 was characterized by a more frequent occurrence of complex karyotypes. In addition, approximately 20% of cases had TdT positivity, complex karyotypes, and anomalies of chromosome 5 and/or 7, a pattern not observed in the other FAB subsets. Finally, 80% of anomalies of chromosome 5 and/or 7 in AML-M0 were comprised within complex karyotypes, whereas only 13% of the remaining FAB cases carried this feature. In summary, AML-M0 frequently expresses immunophenotypic and karyotypic aspects that are likely to identify a "stem cell" pattern.
authors.affiliation: Cattedra di Ematologia-Ospedale S. Eugenio and Cattedra di Immunoematologia, Università di Roma Tor Vergata, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Venditti
authors.forename: G
authors.initials: G
authors.lastname: Del Poeta
authors.forename: F
authors.initials: F
authors.lastname: Buccisano
authors.forename: A
authors.initials: A
authors.lastname: Tamburini
authors.forename: M C
authors.initials: MC
authors.lastname: Cox
authors.forename: R
authors.initials: R
authors.lastname: Stasi
authors.forename: A
authors.initials: A
authors.lastname: Bruno
authors.forename: G
authors.initials: G
authors.lastname: Aronica
authors.forename: L
authors.initials: L
authors.lastname: Maffei
authors.forename: G
authors.initials: G
authors.lastname: Suppo
authors.forename: M D
authors.initials: MD
authors.lastname: Simone
authors.forename: L
authors.initials: L
authors.lastname: Forte
authors.forename: V
authors.initials: V
authors.lastname: Cordero
authors.forename: M
authors.initials: M
authors.lastname: Postorino
authors.forename: V
authors.initials: V
authors.lastname: Tufilli
authors.forename: G
authors.initials: G
authors.lastname: Isacchi
authors.forename: M
authors.initials: M
authors.lastname: Masi
authors.forename: G
authors.initials: G
authors.lastname: Papa
authors.forename: S
authors.initials: S
authors.lastname: Amadori
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000145:classification* / Q000235:genetics / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged