ABSTRACT
Chronic lymphoctic leukemia [CLL] is an acuired clonal Lymphoroliferative disorder characterized by a highly variable clincal course, the biological mechanisms underlying such variability remain largely unclear and the issue of identifying in CLL parameters, which bear predictive implication, is becoming of greater relevance in view of the progressive change in the management of this disease. Mutation or deletion of the P53 gene is the most common genetic event in human malignancy, being mutated in approximately 50% of all human tumors and repeted as well in a number of hematological malignancies This study was conducted aiming to determine the frequency of P53 protein expression in Iraqi CLL patients by immunohistochemistry [IHC] and to evaluate its correlation with various parameters which bear prognostic value in this disease. The study included a total of 82 CLL cases in whom bone marrow biopsies were performed at diagnosis [67cases] or follow up [15cases / at the Department of Hematology Teaching Laboratory, in Baghdad .21edical City Teaching Hospital in the period between Jan 1987 and Dec 2001. The clinical records, blood films, bone marrow aspirates and biopsy slides were re-exanzb7rd and section from paraffin blocks were used for P53 IHC staining. P53 expression was detected in 13 of the total 83 CLL patients [15.8%] with frequency of 13.3% [967] in the newly diagnosed patients. In the follow cases the frequency was almost double that of the newly diagnosed group reaching frequency of 26.6% [115]. In the newly diagnosed cases P53 expression was not correlated with age, gender, and hemoglobin level, and platelet count, percentage of prolymphocyte in the peripheral Blood, Binet clinical stage or with the pattern of bone marrow involvement. However it was significantly correlated with total leukocyte count [P=0.03] and absolute count [P=0.04]. This finding may indicate that P53 positivity is associated with poor prognosis, since absolute lymphocyte count had been documented to be a poor prognosis factor in CLL