Loss of Blood Group Antigens in Haematolymphoid Malignancy: A Case Series from a Cancer Institute from North East India.

Introduction: Altered expression of blood group antigens has been reported to be associated with both solid as well as haematological malignancies. This usually results from genetic mutation leading to incomplete as well as abnormal synthesis of antigens. Transitional loss of RBC antigens especially from ABO system is most commonly found in haematological malignancies causing blood group discrepancies and followed by reversal to its historical blood group during remission. Loss of A, B antigens has also been associated to play a role in lung, bladder and colon cancers. However not much data is available regarding haematological malignancies. Methods and Methodology: Retrospective review of blood group discrepancy (Forward group) in patients admitted for haematolymphoid malignancy at our institute was done during a period of 3.5 years (13/3/2020 till 12/9/2023). Blood grouping done by Column agglutination test were repeated by conventional tube method. Further confirmation of the group was done by saliva test and adsorption elution test as indicated. The detail history of the patient was collected from the hospital records and analysed. Results: A total of 7 patients presented with either loss or decrease in antigen expression. Most common diagnosis was Acute Myeloid Leukaemia (AML) with FLT3 mutation and most common antigen affected was A. Conclusion: Haematolymphoid malignancies has been associated with loss of blood group antigens causing group discrepancy. Blood transfusion is an integral part of the supportive care in these patients. Hence, proper work up of blood group discrepancy cases should be done and recorded so as to prevent delay in blood transfusion. [ABSTRACT FROM AUTHOR]