[Contribution of RT-PCR for diagnosis of chronic myeloid leukemia]

The molecular analysis of chromosomal abnormalities associated with hematological malignancies allowed the identification of genes involved in theses rearrangements as well as of some recurrent mechanisms. Polymerase chain reaction [PCR] tools are now available to detect these rearrangements, allowing a better follow-up of these diseases. Chronic myeloid leukemia is a myeloproliferative disorder characterized by a reciprocal translocation t[9;22][q34;q11] which results in a bcr-abl fusion gene. Retro-transcription polymerase chain reaction [RT-PCR] is used to detect bcr-abl to establish diagnosis and to monitor patients. We report here the results of 30 patients samples tested in the hematology laboratory at Pasteur Institute, diagnosed as chronic myeloid leukemia and monitored with RT-PCR. Our results highlight the interest of molecular tools to diagnose and monitor patients mainly when cytogenetic techniques are irrelevant such as cases with complex chromosomal rearrangements or when patients achieve Philadelphia negativity after treatment

[Cytology and immunophenotyping of acute promyelocytic leukemia]

Acute promyelocytic leukaemia [AML3] is characterized by particular clinical and biological features. We report the cytology and the immunophenotype of 14 AML3 from which 3 were AML3v. A double negativity of HLA-DR and CD34 is found in 12 cases and aberrant expression of CD2 in 2 AML3v. Aberrant expression of CD56 and CD22 was shown in, respectively, one case, CD15, CD65 and CD117 expressions were variable. Cytological diagnosis is often evident, although in some cases, it is not typicaland immunophenotype will contribute to the diagnosis