Angioimmunoblastic lymphadenopathy: comprehensive review

Pathogenesis of Human Reactive-Appearing «Non-Monomorphous» Malignant Lymphoproliferative Disorders: A Hypothesis

Human reactive-appearing « non-monomorphous » malignant disorders, such as Hodgkin's disease, T-cell-rich B-cell lymphomas and angioimmunoblastic lymphadenopathy display a peculiar and unifying characteristic, which biologically differentiates them from « monomorphous » non-Hodgkin's lymphomas. It consists in the coexistence within the pathologic tissue of a polyclonal, normal-appearing, presumed reactive cellular component, mainly composed of T-lymphocytes together with a clonal cell component constituting a minority of the pathologic mass. To explain the long-lasting coexistence of such polymorphic cell populations in the pathologic tissue of synchronous and metachronous localizations of the disease, it is hypothesized that they are interconnected by « biological interactions » which determine and sustain the pathologic process. Based on the biological characteristics of an experimental model (the follicular center cell « lymphoma » of the SJL murine strain), it is suggested that these human « non-monomorphous » malignant diseases should be regarded as a continuous spectrum of lymphoproliferative disorders sustained by a biological loop which interconnects different cell populations able to stimulate each other for growth.

Systemic lupus erythematosus-associated lymphoproliferative disorder: report of a case and discussion in light of the literature

A case of autoimmune disease-associated lymphadenopathy (ADAL) with histological, immunophenotypic, Epstein-Barr virus (EBV) in situ hybridization, and genotypic analyses is presented. The patient had a well-documented history of systemic lupus erythematosus (SLE) and was found at autopsy to have massive lymphadenopathy, thymic enlargement, pulmonary nodules, and polyclonal serum dysproteinemia. Histological examination revealed a polymorphous lymphoid infiltrate containing many plasma cells, rare immunoblasts, and a pronounced arborizing vasculature. No foci of necrosis were found and there was no evidence of lymphocyte depletion. The plasma cells were immunophenotypically polyclonal and no EBV mRNA (EBER-1) or gene rearrangements were identified. The unusual gross features, which resembled a malignant lymphoproliferative process, as well as the unusual histological features make this case a notable addition to the spectrum of atypical lymphoproliferative disorders associated with an autoimmune disorder. We conclude that although reminiscent of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD), this case lacks the diagnostic features of AILD, and is, perhaps, best classified as an autoimmune disease-associated lymphadenopathy (ADAL).