الفهرس | Only 14 pages are availabe for public view |
Abstract The c-kit receptor (CD117), the product of c-kit proto-oncogene is a transmembrane tyrosine kinase receptor that is thought to play an important role in hematopoiesis (D’Arena et al; 1998). Up to 4% of normal bone marrow mononuclear cells including stem cells, committed progenitor cells and mast cells bear the CD117 antigen (Smith et al; 1994). In addition, CD117 is expressed by the primitive CD34 hematopoietic stem cells and is also demonstrated on the blasts of 30-100% of acute myeloid leukemia (AML) cases but rarely on lymphoblasts. Therefore, several investigators have used CD117 expression to exclude lymphoblastic origin of blasts (Uckan et al; 2000). Moreover, Nomdedèu et al (1991) found that CD117 expression yielded a higher score in the system currently applied for the diagnosis of biphenotypic acute leukemia (BAL), as its myeloid specificity is grater than that of CD13 and CD33. CD117 marker analysis can be performed by flow cytometric or immunohistochemical techniques. Dunphy et al (2001) compared the results of CD117 analysis by flow cytometry and immunohistochemical techniques, and concluded that it is better detected by flow cytometry. Aim of the work: Assessment of the reliability of CD117 marker in the differential diagnosis of acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), and to prove its value to br included on a routine basis for immunophenotypic diagnosis of acute leukemias. Patients and methods: An adequate number of patients diagnosed as acute leukemia (AML and ALL) will be subjected to: - Full history (through clinical examination). - Complet blood picture (CBC). - Bone marrow aspiration. - Immunophenotyping (IPT). - Analysis of CD117 expression by flow cytometry. |