Background: CD34 is a marker of HSCs and haematopoietic progenitor cells as well as a marker of several other non-haematopoietic cell types. There is much debate on whether expression of CD34 on malignant myelogenous leukaemia blast cells affect the prognosis and response to treatment or not and if it is an independent prognostic factor or affected by other prognostic factors, especially the cytogenetics.
Methods: This prospective study had been carried out at Haematology Unit, Zagazig University Hospitals. It included 90 denovo AML patients. CD 34 expression was identified by Flowcytometric studies of bone marrow aspirate. it was considered positive if a cut-off level of 10% expression was exceeded. This was then analysed to detect its impact on outcome and its correlation to other risk factors especially cytogenetics.
Results: sixty (66.7%) of the AML patients were CD34 positive and their survival was shorter than patients with negative CD34 expression. CD34 positive AML cases had lower rate of achievement of complete remission. CD34 positivity was significantly linked to less differentiated FAB subtypes (M0, M1, and M2) as well as non-favorable risk cytogenetics. However, multivariate cox regression analysis proved that CD34 positivity confers an independent poor prognostic impact apart from its association with these poor risk factors.
Conclusions: CD34 expression is a poor prognostic biomarker of survival in AML patients, independent from other poor prognostic factors. Its role in AML different subgroups layered by different gene mutations and chromosomal aberrations needs further extensive studying.