Donor or recipient origin of post-transplantation lymphoproliferative disorders: evaluation by in situ hybridization.

Post-transplantation lymphoproliferative disorders (PTLDs) have been reported after bone marrow and solid-organ transplantation. It might be of interest to know the origin of PTLDs, because it has been suggested that a donor origin could be related to a better prognosis. We studied five cases of PTLD in sex-mismatched allografted recipients by in situ hybridization technique for chromosome Y on isolated cells as well as on frozen and on routinely fixed and paraffin-embedded material. Two proved to be of donor origin, including the only case of PTLD arising in the graft, and three of recipient origin. The best results were obtained on isolated cells, but it must be emphasized that hybridization on tissue sections from frozen material or from material fixed in formalin or in formalin-acetic acid-alcohol and then paraffin embedded also gave good results. Hybridization after fixation in Bouin's liquid was not reliable. These results suggest that evaluation of the origin of PTLDs can easily be performed on routinely processed cytologic and histologic material.