BTK and vascular disorder: One possible explanation for this difference is the fact that immunosuppression in SCD is characterized by functional hyposlenism and vasculopathy, whereas, in hematological—especially lymphoid—malignancies by the lack or the dysfunction of B cells responsible for the production of specific antibodies, the use of anti-CD20 monoclonal antibodies, BTK and/or BCL-2 inhibitors further depletes a patient’s B-cell pool.