ZAP-70 expression in B-chronic lymphocytic leukemia in Sudanese patients

Abstract

Background: Chronic lymphocytic leukemia is the most common form of leukemia in adults. The prognostic impact of ZAP-70 in CLL has been reported in several studies. The aim of conducting this study was to investigate the prevalence of ZAP-70 in Sudanese patients with chronic lymphocytic leukemia attending Khartoum Oncology Hospital.

Materials and Methods: A total of 93 newly diagnosed patients with chronic lymphocytic leukemia were enrolled in this study. Lymphadenopathy and organomegaly were assessed in all participants using clinical examination, chest radiography, and abdominal ultrasound. Full blood count was carried out by an automated hematology analyzer. ZAP-70 was evaluated using flowcytometry on peripheral blood samples. ZAP-70 was defined as positive expression at a cutoff level of 20%.

Results: There were 63 (67.7%) males and 30 (32.3%) females and the median age of the group was 63 years; 68 patients (73.1%) were presented with anemia and 66 (70.9%) had lymphadenopath;y. Majority of our patients 35 (37.6%) were in Rai stage IV. ZAP-70 positivity was detected in 21 patients (22.6%). There was no statistically significant association of ZAP-70 with age, sex, lymphadenopathy, organomegaly, hemoglobin concentration, total white blood cell count, platelet count and Rai staging system (p-value > 0.05).

Conclusion: Only 21 patients (22.6%) were ZAP-70 positive. There was no association between ZAP-70 and the study variables. Further studies to evaluate prognostic role of ZAP-70 in Sudanese patients with chronic lymphocytic leukemia are recommended.

Keywords: ZAP-70, chronic lymphocytic leukemia, flowcytometry