To the Editor.—There is a spectrum of lymphoproliferative disorders ranging from atypical hyperplasia to frank lymphoma. At times, the histologic picture may be very confusing and the pathologist may have great difficulty in categorizing a lesion.1 This problem is compounded in organ transplant recipients whose lymphoid tissues are exposed to a variety of antigenic stimuli from the histocompatibility antigens of the allograft, heterologous antilymphocyte globulin, a broad spectrum of infectious agents, and a considerable number of medications. By far, the most important lymphoproliferative disorder seen in these patients, is malignant lymphoma, which comprises 33% of the malignant neoplasms that occur so commonly after transplantation.2 However, a number of lymphoproliferative disorders may be mistaken for lymphomas in transplant recipients.
The article entitled "Pseudolymphoma in Renal Allograft Recipients" by Geis et al in the Archives (113:461-466, 1978) draws attention to one such condition. This has histologic features of a non-Hodgkin's