Undiagnosed lymphoma detected during routine histocompatibility crossmatch: 3 case reports

Unexpected transmission of donor-derived diseases, including infections and malignancies, through organ transplantation are occasionally observed and reported. Subclinical, or otherwise undiagnosed, hematological malignancies in potential donors are rare events and typically not identifiable via standard donor evaluation or laboratory testing. Flow cytometric crossmatching is a specialized assay routinely performed in clinical histocompatibility laboratories for the evaluation of immunological compatibility between recipients and organ donors through the detection of donor-specific antibodies. Here, we report 3 unusual cases of undiagnosed hematological malignancies in the organ donors that were identified during routine pretransplant flow cytometric crossmatching evaluation through abnormalities observed in the lymphocyte staining profile, size, and relative cell events that effectively prevented potential transmission of such donor-derived malignancies to the immunocompromised recipients.