LYMPHOPROLIFERATIVE DISEASE OF DONOR ORIGIN ARISING IN PATIENTS AFTERORTHOTOPIC LIVER-TRANSPLANTATION

Background. Lymphoproliferative disease is a well recognized complicat ion of organ transplantation and in many cases is associated with Epst ein-Barr virus (EBV) infection. It is widely thought that posttranspla ntation lymphoproliferative disease (PTLPD) arises from recipient lymp hoid cells. However, solid organ allografts are likely to include dono r lymphoid tissue around or within the transplanted organ. Therefore, it is possible that transplanted donor lymphocytes may proliferate to form PTLPD. Methods. The genetic origin of tumor cells was determined by microsatellite DNA fingerprinting using the polymerase chain reacti on (PCR). Their EBV association and clonality were established by PCR amplification of DNA extracted from formalin fixed, paraffin embedded tissue using primers to conserved regions of the EBV genome and the im munoglobulin heavy chain gene, respectively. Results. The authors have demonstrated two cases of lymphoproliferative disease that were deriv ed from donor lymphocytes in orthotopic liver transplant recipients. I n both cases, the proliferating cells were EBV DNA positive. Furthermo re, the PTLPD was restricted to allograft tissue around the porta hepa tis. However, the two cases differed in their clonal properties and re sponse to treatment: one case was oligoclonal and regressed after anti viral therapy and a modest reduction of immunosuppression, whereas the other contained two clonal populations and was controlled only after treatment with antineoplastic chemotherapy. Conclusion. This study has demonstrated two cases of PTLPD that were derived from donor lymphoid tissue. Although both cases were associated with EBV and remained loc alized to allograft tissue, their clonality and response to therapy di ffered.