Posttransplant diffuse large B-cell lymphoma of "lymphomatoid granulomatosis" type.

The exact relationship between lymphomatoid granulomatosis (LyG) and posttransplant lymphoproliferative disorders (PTLDs) is not clear. Both are observed in immunodeficient patients and are Epstein-Barr virus driven. These disorders are, however, considered distinct based upon the immune response elicited; LyG is T-cell rich while PTLDs are T-cell poor. We describe a case of LyG-type diffuse large B-cell lymphoma (DLBCL) in a lung transplant recipient. The unusual features include rare occurrence of LyG in a posttransplant setting, systemic involvement by LyG variant of DLBCL in a solid organ transplant recipient, paucity of T-cells in this LyG type lymphoma, and subcutaneous panniculitic pattern in a B-cell lymphoproliferative disorder. This first report of systemic LyG variant of DLBCL in a posttransplant setting has features suggesting similarities and overlap between LyG and PTLD.