Clinical features of childhood acute myeloid leukemia with specific gene rearrangements

Specific gene rearrangements seem to distinguish distinct subsets of acute myeloid leukaemia (AML) with different features and prognosis, and some reports suggest that the epidemiological distribution of AML could vary among countries.1, 2 To date, cytogenetic examination has been used to study the frequency of these genetic alterations in a large series of children3, 4, 5 with AML; nevertheless, in a proportion of cases, these gene rearrangements may be cryptic and undetectable by conventional cytogenetic techniques.6, 7 To evaluate the frequency of specific gene rearrangements, the corresponding clinical morphological features at diagnosis and the potential prognostic impact on patients' long-term survival, we screened by RT-PCR five different chimaeric transcripts (AML1-ETO, CBF-MYH11, PML-RAR, MLL-AF9 and BCR-ABL) in a series of 270 Italian children with AML, treated with AIEOP-LAM 87–92, BFM 83-93 and AIDA protocols between 1988 and 1998, and whose RNA were available and morphology had been centrally reviewed.