Haematological characteristics, FAB and WHO classification of 153 cases of myeloid acute leukaemia in Tunisia

A complete blood analysis with a careful morphologic examination of peripheral blood and bone morrow smears completed by cytochemical reaction will help to classify the most acute myeloid leukaemia (AML). Actually, the study of other cytogenetis and immunophenotypic markers are now necessary to confirm diagnosis. The World Health Organisation WHO classification (2001) incorporates theses approaches. The purpose of this study is a bioclinical review according to the WHO recommendations in 153 cases of LAM diagnosed between January 1998 and December 2003. The patients were aged 2 months to 90 years with sex ratio (M/F) of 1,22. The morphologic conclusion was difficult in 12% cases. Presence of dysplasia is noted in 50% of cases with multilineage dysplasia in 42% of cases. Our results showed cloned chromosomal abnormalities in 57% of cases (t(8;21): 12%, t(15;17): 10%, Inv16: 1,3%, 11q23: 2,6% et complex karyotype: 14,3%). In 69% of cases with multilineage dysplasia, the karyotype was normal. 3 cases of LAM were noted at patients treated for breast cancer with chirurgic chemotherapy and radiotherapy 3, 4 et 5 years after treatment (LAM3 with t(15;17), LAM4 with genetic abnormalities of chromosomes 3, 5, 7, 8, 9, 14 et 16 et LAM 6 with genetic abnormalities of chromosomes 4, 7, 12, 14, 19 et 21). In WHO classification, cytology is essential in diagnosis of LAM even if the karytype have an important prognostic value. Research of signs of dysplasia lineage after lineage constitutes an important microscopic work and it is difficult to quantify dysplasia when the lineage is poor.