Deciphering the Complex Intertwining Between Cytopenia and Transfusion Needs After CAR-T-Cell Therapy for B-Cell Malignancies

Immune-effector-cell-associated hematotoxicity has emerged as the most common CAR-T-cell-related complication in the real-world setting. Therefore, transfusion of blood components remains unavoidable in many patients treated with CAR-T cells to alleviate symptomatic anemia and prevent major bleeding events. This study investigates predictive factors associated with the transfusion requirement in patients receiving anti-CD19 CAR-T-cell therapy for B-cell malignancies in a real-world setting and the potential correlation between transfusion needs, ICAHT, and long-term survival outcomes. Among 90 investigated patients, 51 (56.7%) received at least one transfusion in the three months post-infusion (33.4% received only RBC concentrates, and 23.4% received both RBC and platelet transfusions). The highest transfusion needs occurred in the first month post-infusion, with 50 transfused patients (55.5%). Early transfusion-requiring cytopenia was associated with pre-infusion altered bone marrow function, patients-related factors, including female sex, and acute inflammatory toxicities. The incidence of late cytopenia was mainly predicted by the need for pre-infusion transfusion support. Patients receiving platelet transfusions were characterized by an inferior progression-free (<i>p</i> = 0.013) and overall survival (<i>p</i> = 0.005). CAR-T-cell-treated patients can experience a high transfusion burden, impairing their quality of life, potentially affecting survival outcomes, and resulting in overutilization of clinical resources.