Search

BACKGROUND: Aberrant antigen expression is an unexpected antigen that is detected on lineage in question without alteration of lineage definition. Immunophenotypic aberrancies are thought to predict treatment outcome in acute myeloid leukemia (AML). Some studies reported an adverse prognostic association, while others failed to show any association. AIM: To determine percentage of lymphoid antigens expression in adult AML patients and correlate them with hematological parameters and response to induction chemotherapy protocol. SUBJECTS AND METHODS: Peripheral blood and bone marrow fresh samples from 81 cases of de novo AML were included in this study from November 2018 to October 2019. Hematological parameters were obtained from patients' medical records. Aberrant antigens expression was detected using flow cytometry at the diagnosis. Patients were evaluated after one cycle of chemotherapy regarding remission status. RESULTS: Out of 81 patients, 60 patients had completed data for evaluation. CD7, CD19 expression, and co-expression of CD7 and CD2 were found in 60%, 10.7%, and 10.7% of patients, respectively. Statistically significant associations were found between initial hemoglobin level and aberrant expression as patients with aberrant expression have higher hemoglobin level than patients without aberrant expression. Complete remission was achieved in 29 out of 60 patients (48.3%) with standard 3 and 7 protocol, whereas 31 patients did not achieve complete remission. There is no statistically significant association between aberrant expression and treatment response to the first cycle of chemotherapy protocol (P > 0.05). CONCLUSIONS: CD7 is the most frequent aberrant antigen expressed in this Iraqi AML patient group. Hemoglobin level was higher in patients with aberrant expression. No significant association between aberrant expression and response to the first cycle of induction.

Background: Leukemic blasts in acute lymphoblastic leukemia (ALL) may have immunological features of both lymphoid and myeloid lineages known as aberrant myeloid antigens expression in ALL, which are explained as abnormal genetic program of leukemic cells that lead to lineage infidelity. In this study, CD13, CD14, and CD33 (which are the most frequent myeloid antigens associated with aberrant antigens expression in ALL) were investigated. Objectives: To evaluate the occurrence of aberrant myeloid antigens expression in childhood ALL and its effects on complete remission and other parameters. Materials and Methods: This study was conducted on 31 pediatric patients with newly diagnosed de novo ALL (27 B-ALL, 4 T-ALL) in Children Welfare Teaching Hospital/Medical City of Baghdad; diagnosis of ALL based on morphology and cytochemistry, CD13, CD14, CD33 were investigated as myeloid antigens using four-color flow cytometry. Results: Five cases of ALL (16.13%) out of 31 cases were confirmed to have aberrant myeloid antigens expression (CD13 was expressed in all five cases, CD33 was expressed in three cases, and CD14 was not expressed in any of these five cases). Complete remission was achieved in 90.30% (28 patients) and all cases with aberrant myeloid antigens expression achieved complete remission; however, despite this, there was no significant difference in complete remission between myeloid-positive (MY+) and myeloid-negative (MY−) cases, P > 0.05. Regarding other parameters, there were significant statistical differences in lactate dehydrogenase (LDH), hemoglobin value, and bone marrow (B.M.) blasts percent at diagnosis between MY+ and MY− cases, P< 0.05; however, there was no significant differences in leukocytes count, platelets count, peripheral blood blast percent at diagnosis, age, and gender, P > 0.05. Conclusions: The most frequent aberrant myeloid antigens expression in childhood ALL is CD13 and less frequently is CD33 while CD14 showed no expression; myeloid antigens expression in ALL may have better prognosis as they have lower B.M. blast percent and LDH value.