Indication for FLT3 and CD34 Among Acute Myeloid Leukemia in Sudanese Patients

Abstract

Background: Multiparametric flow cytometry (MPFC) is an effective method for AML diagnosis, classification, characterization, and MRD monitoring. Abnormal surface and cytoplasmic antigen patterns can form leukemia-associated immunophenotypes (LAIPs), enabling sensitive MRD detection. MPFC is applicable to more than 90% of AML cases, offering broad utility compared with PCR-based molecular MRD testing. AML outcomes vary widely, and prognosis is influenced by age, performance status, and cytogenetic abnormalities. CD34 is an important cell-surface glycoprotein used in AML immunophenotyping. CD34 contributes to cell adhesion and may facilitate interactions between hematopoietic stem/progenitor cells and the bone marrow stromal microenvironment. The FLT3 protein is primarily expressed on early hematopoietic progenitor cells, especially CD34-positive cells in the bone marrow, highlighting its important role in the initial stages of blood cell formation. Although FLT3 is also present in various other tissues, its major function is to act as an important regulatory receptor in hematopoiesis. This study aimed to detect CD34 and FLT3 among Sudanese patients with AML in order to assist in diagnosis and prognosis. Methodology: 100 AML patients were enrolled in this study, they were 40% males and 60 females. Complete blood count was assessed via Beckman Coulter device and CD34 was detected through flow cytometer assessment and FLT3 was detected through molecular detection through PCR. Data analysis was conducted by statistical package of social science. Patients were recruited from Khartoum center for Nuclear and Isotope therapy -Sudan. Result: Out of collected data of patients’ files, CD34 detection, which was conducted via flow cytometer, it showed 21% with no CD34 and 79% with presence of CD34. FT3 mutation also detected 18% with wild type and 82% as mutant. Conclusion: Males were less than females, CD34 was detected among 21% and FLT3 mutation detected among 18% as wild, those considered as poor prognosis phase.

Introduction

• The study was conducted at the Khartoum Center for Nuclear and Isotopic Therapy.
• It included 100 AML patients aged 16–67 years.
• Patient information included age, AML subtype according to the FAB classification, and extramedullary involvement.
• Laboratory investigations included:
  • Complete blood count.
  • Peripheral blood and bone-marrow blast percentages.
  • FLT3 mutation detection using PCR.
  • CD34 detection using flow cytometry.
  • Blood-film examination.
• Data were analyzed using SPSS version 20.

Main Results

Methodology

The study was a cross-sectional study conducted at the Khartoum Center for Nuclear and Isotopic Therapy.

• Participants: 100 patients diagnosed with AML.
• Age: 16–67 years, with a mean age of approximately 49.4 years.
• Sex: 40% male and 60% female.
• Patient information included AML classification, age, and extramedullary involvement.
• Complete blood counts were performed using a Beckman Coulter analyzer.
• FLT3 mutation was detected using PCR.
• CD34 expression was measured using flow cytometry.
• Blood and bone-marrow films were examined to determine blast percentages and leukemia type.
• Data were analyzed using SPSS version 20.

Conclusion

Patients showed significant hematological abnormalities, including high WBC counts, low hemoglobin and platelet levels, and increased blast percentages. Bone marrow blasts (63.2%) were higher than peripheral blood blasts (52.8%), indicating substantial bone marrow involvement. AML-M4 (24%) was the most frequent FAB subtype, followed by M5 (19%) and M3 (16%); M0 (1%) was the least frequent. Extramedullary infiltration was present in 60% of patients. The major clinical manifestations included splenomegaly (28%), lymphadenopathy (27%), and hepatomegaly (23%). Bone marrow hypercellularity was observed in 80% of patients. CD34 expression was detected in 79% of patients, while 21% were negative. FLT3 mutation was detected in 82% of patients, compared with 18% who were wild type. Overall, AML patients demonstrated considerable clinical, hematological, morphological, and molecular heterogeneity. The findings emphasize the importance of combining hematological, morphological, immunophenotypic, and molecular investigations for comprehensive AML characterization and clinical assessment.

References

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Copyright

Copyright © 2026 Mohammed Fathi Ibrahim Madani, FathElrahman Mahdi Hassan Gameel, Mahdi H. A. Abdalla, Amira Hassan AbdAlrahman Arman , Ahmed Siddig Akasha Hassan. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.