Cancer type predicts alloimmunization following RhD-incompatible RBC transfusions

Area of Science:

• Hematology
• Transfusion Medicine
• Oncology

Background:

• RhD-negative oncology patients receiving RhD-positive red blood cell (RBC) transfusions may have lower sensitization rates.
• Clinical factors influencing D antigen alloimmunization in this population require further definition.

Purpose of the Study:

• To identify clinical factors associated with D antigen alloimmunization in RhD-negative oncology patients receiving RhD-positive RBC transfusions.
• To determine the incidence of alloanti-D antibody formation in this patient group.

Main Methods:

• Retrospective analysis of 4295 RhD-positive RBC transfusions in 545 RhD-negative oncology patients over 4 years.
• Recorded patient demographics, oncology diagnosis, and transfusion history.
• Assessed alloanti-D incidence via antibody detection tests at least 28 days post-transfusion.

Main Results:

• A 14% (76/545) incidence of D antigen alloimmunization was observed.
• Myelodysplastic syndrome (23%) and solid malignancies (22.6%) were significantly associated with higher alloimmunization rates compared to acute leukemia (7%).
• Diagnosis type was the sole significant factor associated with alloimmunization.

Conclusions:

• The sensitization rate to the D antigen in RhD-negative oncology patients is 14%.
• Specific diagnoses, including myelodysplastic syndrome and solid cancers, predispose patients to RhD alloimmunization.
• Understanding these risk factors aids in optimizing RhD-negative RBC utilization during shortages.