ALBERT

Description: Recent molecular evidence suggests an association with a new herpesvirus, Kaposi's sarcoma-associated herpesvirus (KSHV/HHV-8), and primary effusion lymphomas (PELs). PELs have a characteristic morphology, phenotype, and clinical presentation, with malignant effusions in the absence of a contiguous solid tumor mass. We have established a cell line (KS-1) from a KSHV-positive human immunodeficiency virus (HIV)-negative patient with pleural cavity-based lymphoma that was passaged into triple-immunodeficient BNX mice. In contrast to cell lines from body cavity-based lymphomas derived from HIV-positive individuals that contain both KSHV and Epstein Barr viral genome, these cells contain only KSHV, allowing for uncontaminated virologic studies. Ultrastructural examination identified malignant cells with features of late differentiating B cells (immunoblasts). Cells with viral cytopathic effect contained typical 110-nm intranuclear herpesvirus nucleocapsids and complete cytoplasmic virions, confirming the association of PEL with KSHV.

Description: The clonality of nodular lymphocyte-predominant Hodgkin's disease (NLPHD) and the relationship to composite or sequential large-cell lymphomas (LCLs) is poorly understood. Clonal Ig heavy-chain gene rearrangements (lgHGR) have infrequently been observed in NLPHD by Southern hybridization. The goals of this study were (1) to determine if IgHGR could be identified by polymerase chain reaction (PCR) techniques in the LCL associated with NLPHD; (2) to determine if the lgHGR identified in the LCL could also be found in the associated NLPHD; and (3) to determine if Epstein-Barr virus (EBV) played a role a role in histologic progression to LCL. Using consensus primers to conserved regions in the lgH variable (V) and joining (J) region genes, we analyzed formalin-fixed paraffin-embedded sections from the biopsies of 25 patients referred to the National Cancer Institute (NCI) registry for NLPHD and LCL using both single-step and seminested V-J PCR. The histologically aggressive component was further subclassified as frank LCL or as L&H-cell-rich, but not fulfilling criteria for LCL. Matched samples representing both NLPHD and aggressive components were available in 13 cases. In 12 cases, only one component was available (aggressive, n = 8; NLPHD, n = 4). In addition, we also amplified, with 32P labeling, 12 cases of NLPHD without associated LCL. Two clonal IgHGR were identified in 29 cases (7%) of typical NLPHD, both of which were associated with LCL containing a similar sized band by PCR. The clonal identity of the bands in the NLPHD and associated LCL was confirmed by sequencing the products in these two cases. Eight of 10 cases (80%) of LCL associated with NLPHD contained a clonal band by this technique. By contrast, none of the cases classified as L&H-cell- rich contained an IgHGR. The single-step and seminested PCR methods produced identical results. All clonal LCLs were studied for EBV sequences by in situ hybridization using the EBER1 probe, and were negative. We conclude that the LCLs associated with NLPHD are clonal B- cell malignancies. However, by these methods, the same clone can be identified in only a minority of cases of NLPHD and LCL. EBV does not appear to play a role in histologic progression. Moreover, our results suggest that many cases suspected of being LCL may actually represent NLPHD with increased numbers of L&H cells. In histologically equivocal cases, the diagnosis of LCL should be reserved for those cases in which a clonal B-cell neoplasm can be demonstrated.

Description: The recently identified Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8), has been found to be consistently associated with an unusual subset of acquired immunodeficiency syndrome-related lymphomas, the so-called body cavity-based lymphomas (BCBL) or primary effusion lymphomas (PEL). These lymphomas are characterized by a unique spectrum of morphologic and molecular characteristics, and grow as lymphomatous effusions without an identifiable contiguous tumor mass. Until now, efforts to delineate the role of KSHV in the pathogenesis of PELs have been hampered by the lack of appropriate model systems and the concomitant presence of Epstein-Barr virus (EBV) in nearly all cases examined, and in all previously established cell lines. We now report the establishment and characterization of a novel PEL cell line, BC-3, which is KSHV+ by polymerase chain reaction (PCR) but EBV- as assessed by a variety of methods including PCR for EBER, EBNA-2, and EBNA-3C. This cell line was established from a lymphomatous effusion obtained from an HIV- patient, and has immunophenotypic and molecular features consistent with the diagnosis of PEL, including an indeterminate immunophenotype with a B-cell immunogenotype and lack of c-myc proto-oncogene rearrangements. Pulsed-field gel electrophoresis shows an intact KSHV genome of about 170 kb both in the cell line and in the viral isolate, whereas herpesvirus-like capsids are visible by electron microscopy. Consequently, the BC-3 cell line represents an invaluable tool as a source of KSHV, for both the evaluation of the pathogenic potential of this virus and the mechanistic characterization of its role in the development of Kaposi's sarcoma and malignant lymphoma.

Description: Recent molecular evidence suggests an association with a new herpes virus, Kaposi's sarcoma-associated herpes virus (KSHV/HHV-8), and primary effusion lymphomas (PEL). PELs have a characteristic morphology, phenotype, and clinical presentation with malignant effusions in the absence of a contiguous solid tumor mass. Most cases of PEL have occurred in human immunodeficiency virus (HIV)-positive male patients who are coinfected with Epstein-Barr virus (EBV). This report describes two cases of PEL in HIV- and EBV-negative women. In one patient, a pleural cavity PEL was preceded by classic Kaposi's Sarcoma (KS) of the lower extremities. In the second patient, PEL developed in an artificial cavity related to the capsule of a breast implant. Both cases had the characteristic morphologic appearance of high-grade anaplastic/B-cell immunoblastic lymphomas, with loss of B-cell differentiation antigens, clonal immunoglobulin heavy chain gene rearrangements, and expression of activation antigen CD30. Both cases were negative for EBV, herpes virus simplex, and cytomegalovirus (CMV). DNA extracted from both lymphomas and skin KS specimen showed KSHV sequences by molecular analysis. This report expands the spectrum of KSHV-associated disease to include PEL in HIV-negative women.