This retrospective observational study aims to evaluate the distribution of ABO and Rh blood groups among patients diagnosed with acute leukemia. By analyzing medical records from leukemia cases, the study seeks to identify any potential associations between blood group types and the occurrence of the disease.

Acute leukemia is a group of hematologic malignancies characterized by the rapid proliferation of immature blood cells, leading to bone marrow failure and systemic complications. It is broadly classified into two main types: acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), depending on the lineage of the malignant cells. Despite advancements in the understanding of leukemia pathogenesis, the etiology remains multifactorial and incompletely understood.

Recent studies have suggested a potential association between blood group antigens-particularly those of the ABO and Rh systems-and the risk of developing various types of cancer, including hematological malignancies. The ABO antigens are expressed not only on red blood cells but also on epithelial and endothelial cells, and may influence cancer biology through mechanisms involving immune response modulation, cell adhesion, and inflammation.

Several epidemiological investigations have explored the relationship between ABO and Rh blood groups and malignancies such as gastric, pancreatic, breast, and hematologic cancers. However, data regarding their association with acute leukemia are still limited, inconsistent, and often vary across different populations and study designs.

This study is a retrospective observational analysis conducted at the Clinical Pathology Department, South Egypt Cancer Institute, Assiut University. It aims to assess the frequencies of ABO and Rh blood groups among patients diagnosed with acute leukemia over a defined period. The findings will be compared to blood group distributions in healthy blood donors to explore any statistically significant associations.

Understanding whether certain blood group antigens are associated with an increased or decreased risk of acute leukemia may help identify at-risk individuals, contribute to risk stratification, and provide further insight into the biology of leukemogenesis.

Inclusion Criteria:

• Patients diagnosed with de-novo acute leukemia (ALL or AML)
• Diagnosis confirmed between 2022 and 2025
• ABO and Rh blood group data available
• Patients treated at or referred to South Egypt Cancer Institute, Assiut University

Exclusion Criteria:

• Incomplete or missing blood group data
• Presence of other malignancies or chronic systemic illnesses
• History of blood transfusion prior to diagnosis or blood grouping

Patients diagnosed with de-novo acute leukemia (ALL and AML) at South Egypt Cancer Institute, Assiut University, during the period from 2022 to 2025.