Anti-vimentin antibody reactivity with Reed-Sternberg cells of Hodgkin's disease

World Health Organization and beyond: new aspects in the pathology of an old disease

Hodgkin's lymphoma is a highly enigmatic lymphoma disease that still covers most of its secrets up to now. Much effort has been made to successfully wrest at least some of the pathogenetic particularities. The current diagnostic criteria are well established allowing hemato-pathologists to make a clear-cut distinction from other lymphomas in almost all cases. Although classic Hodgkin's lymphoma is curable in the vast majority of cases by treatment with highly aggressive drugs with or without radiotherapy, further molecular studies may lead to the identification of therapeutic targets that enable a more tailored treatment with fewer side effects.

Hodgkin's disease: old and recent clinical concepts

The diagnosis of Hodgkin's disease (HD) is still primarily based on the histopathologic criteria presented by Lukes et al in 1965. Over the past three decades, however, advances in immunohistochemistry, molecular studies, and virologic findings have provided evidence that HD exhibits significant heterogeneity. Whereas the nodular sclerosis subtype is the major subset of the "classic" disease, it has become evident that the nodular, lymphocytic predominance subtype may represent a minor distinct subset, and possibly a distinct disease entity. Furthermore, there is strong evidence that the mixed cellularity subtype may be an Epstein-Barr virus-related disorder. Finally, based on phenotypic and genotypic features, the existence of a "continuum" between a fraction of HD cases, including the lymphocytic depletion subtype, and CD30-positive anaplastic large cell lymphomas has been suggested.

KP1 (CD68)-positive large cell lymphomas: a histopathologic and immunophenotypic characterization of 12 cases

CD68/KP1 antigen expression in a series of 298 non-Hodgkin's lymphoma (NHL) cases, including 41 cases of CD30/Ki-1-positive anaplastic large cell (Ki-1+ ALC) lymphomas, was examined. Among the cases in this series, 12 large cell NHLs, including five centroblastic (G group according to the Working Formulation) NHLs, three immunoblastic (H group) NHLs, and four Ki-1+ ALC lymphomas, were found to express KP1. By extensive immunophenotypic analysis and in situ hybridization, KP1-positive large cell lymphomas of the G and H groups were assigned a B-cell phenotype. The pattern of KP1 staining usually consisted of localized small to medium-sized cytoplasmic dots; only two cases showed diffuse fine granular reactivity. In two of the four Ki-1+ ALC lymphomas tumor cells failed to express a B- or T-cell phenotype and stained positively for lysozyme, whereas in the other two cases they showed a hybrid T/histiocytic, phenotypic profile. KP1 staining of Ki-1+ ALC lymphoma cells was usually intense and showed a diffuse granular cytoplasmic pattern; tumor cells also expressed the CD13 antigen and showed strong reactivity with the anti-CD68 EBM11 antibody. Our results suggest that certain subsets of large "blastic" B-cell lymphomas may simultaneously express the CD68/KP1 histiocyte-specific marker and other myeloid-associated antigens, indicating the necessity of using a multiparameter approach in the determination of cell lineage. Moreover, this study, which demonstrates that the expression of CD68/KP1 and CD30 antigens is not mutually exclusive, supports the view that a fraction of cases diagnosed as Ki-1+ ALC lymphomas (at least those with KP1 expression along with the lack of B- or T-antigen expression) represent true histiocytic lymphomas despite the Ki-1+ phenotype.

High incidence of monoclonal EBV episomes in Hodgkin's disease and anaplastic large-cell KI-1-positive lymphomas in HIV-1-positive patients

A series of selected lymphoid malignancies (LMs) occurring in Italian HIV-1-infected (HIV+) patients, principally intravenous drug users, was investigated. In addition to small non-cleaved-cell (SNCC) and large-cell immunoblastic (LCI) non-Hodgkin's lymphomas (NHLs), a relatively high occurrence of anaplastic large-cell Ki-I-positive (ALC Ki-I+) lymphomas and Hodgkin's disease (HD) was observed, at variance with other reported series of HIV+ patients. Combined results of in situ hybridization and Southern-blot analyses, in conjunction with immunohistochemical detection of Epstein-Barr virus (EBV)-encoded latent membrane protein-I (LMP-I), showed an almost complete association of ALC Ki-I+ lymphomas and HD cases with EBV. The neoplastic cells of both these LMs also showed common immunophenotypic features such as frequent absence of B- and T-cell differentiation markers and expression of the Ki-I activation marker, while SNCC and LCI lymphomas were mainly of mature B-cell origin and Ki-I-. The concomitant high incidence of ALC Ki-I+ lymphomas and HD in a specific group of HIV+ patients, their almost complete association with EBV in clonal and episomal form and the great similarity in differentiation, activation and virological markers which they display suggest that these LMs are pathological variants of a continuous spectrum of HIV-I-associated disorders etiopathologically linked to EBV.

Analysis of antigen receptor genes in Hodgkin's disease

AIM

To analyse the configuration of the antigen receptor genes in Hodgkin's disease.

METHODS

DNA extracted from 45 samples of Hodgkin's disease was analysed using Southern blotting and DNA hybridisation, using probes to the joining region of the immunoglobulin heavy chain gene, the constant region of kappa immunoglobulin light chain gene, and the constant region of the beta chain of the T cell receptor gene.

RESULTS

A single case of nodular sclerosing disease showed clonal rearrangement of the immunoglobulin heavy and light chain genes, all other samples having germline immunoglobulin genes. The nature of the clonal population in the diseased tissue is uncertain, because the intensity of the rearranged bands did not correlate with the percentage of Reed-Sternberg cells present. The T cell receptor genes were in germline configuration in all the samples.

CONCLUSIONS

Antigen receptor gene rearrangement is a rare finding in unselected cases of Hodgkin's disease.

Co-expression of Epstein-Barr virus latent membrane protein and vimentin in "aggressive" histological subtypes of Hodgkin's disease

The presence of Epstein-Barr virus (EBV) genome in Hodgkin's and Reed-Sternberg (HRS) cells, as detected using in situ hybridization (ISH) with biotinylated BamHI "V" probes, along with the expression of EBV-encoded latent membrane protein (LMP) and vimentin was examined in paraffin-embedded sections of 39 immunomorphologically characterized cases of Hodgkin's disease (HD). ISH demonstrated EBV in HRS cells in 15 of 39 cases, whereas LMP expression was detected in 11 of 39 cases, only in the presence of EBV genome detection. With the exception of 1 case, in which HRS cells expressed B-cell-associated antigens, the LMP-positive cases included specimens in which HRS cells were of non-B, non-T phenotype. LMP expression showed a stronger association with lymphocyte depletion (LD) (3/3) and mixed cellularity (MC) (6/11) than with lymphocyte predominance (0/5) or nodular sclerosis (2/20) subtypes. Vimentin expression on HRS cells was found in all the LMP-expressing cases and only in a fraction (13/28) of LMP-negative cases. This study supports the view that HD represents a heterogeneous group of diseases also in terms of EBV association, LMP expression being strongly related to the "aggressive" LD and MC histological subtypes. In light of the supposed interactions between vimentin and LMP, their co-expression on HRS cells, as detected in this study, provides further evidence for a significant role of EBV in the development of a proportion of HD cases.

Immunohistochemistry of Hodgkin and non-Hodgkin lymphomas with emphasis on the diagnostic significance of the BNH9 antibody reactivity with anaplastic large cell (CD30 positive) lymphomas

BACKGROUND

Morphologic and immunohistologic studies were performed on a series of 213 lymphoma cases, including CD30-positive anaplastic large cell (ALC) lymphomas (45 cases), other CD30-positive (18 cases) or CD30-negative (72 cases) non-Hodgkin lymphomas (NHL), cases of Hodgkin disease (HD) (73 cases), and an additional 5 cases exhibiting features of both CD30-positive ALC and Hodgkin lymphomas.

METHODS

The aim was to assess differential expression by tumor cells of CD30/BerH2, epithelial membrane antigen (EMA), and other monoclonal antibodies, including BNH9, an epithelial and endothelial marker that has been found to be reactive with ALC lymphoma cells.

RESULTS

A significantly greater proportion of cases of ALC lymphoma compared with HD exhibited positive results for CD45, EMA, CD45RO, and CD3 in CD30-positive atypical large cells, whereas Reed-Sternberg cells in HD most frequently coexpressed CD15 and CD30 antigens. ALC lymphoma cells reacted with BNH9 MoAb in 10 of the 42 (23.8%) assessable cases, whereas Reed-Sternberg cells reacted with this antibody in 5 of 73 (6.8%) HD cases. Only 3 of 90 (3.3%) NHL cases had positive results for BNH9; they were CD30-negative high-grade or low-grade lymphomas. It was noteworthy that 9 of 10 BNH9-positive ALC lymphomas also were EMA positive. Four of the five cases with morphologic features intermediate between those of HD and ALC lymphoma showed immunohistologic findings (positive results for CD30 and CD15, negative results for EMA, CD45, and BNH9) similar to those frequently observed in the HD cases; conversely, the remaining case showed a profile (positive results for CD30, CD45, and EMA, negative results for CD15) typically observed in ALC lymphomas.

CONCLUSIONS

This study suggests that the differential expression of CD45, EMA, and CD15 could be used in the distinction of ALC lymphomas and HD, whereas it seems that BNH9 antibody reactivity may be of diagnostic use only in that it reinforces the diagnostic value of EMA expression in the differentiation of these entities.

Recent results on the biology of Hodgkin and Reed-Sternberg cells. I. Biopsy material

The most recent sophisticated investigations have provided new and revealing, but also contradictory and controversial information on the biological nature and the cellular origin of Hodgkin and Reed-Sternberg cells (H-RS). Immunophenotypic analyses have shown variable phenotypic antigen expression; but, on balance the data suggest a lymphoid cell expressing T- and/or B-cell-associated markers and certain activation antigens while lacking immunological features of monocytes-macrophages or other lineages. Molecular genetic studies have demonstrated heterogenous findings with respect to rearrangements of T-cell receptor and immunoglobulin genes. Only a small percentage of the cases has rearrangements; this might be due to the threshold of sensitivity of the method combined with the scarcity of the malignant cells. Epstein-Barr virus (EBV) genomes are clonally integrated in the H-RS cells of about half the cases. The significance of these findings--whether EBV is a causative agent or an epiphenomenon--remains to be elucidated. H-RS cells express mRNA and proteins of various cytokines and cytokine receptors implying a predominant role for cytokines in the pathophysiology of HD. The mononuclear and polynuclear H-RS cells are capable of DNA synthesis and nuclear division; the lack of cellular division leads to multinuclearity through the process of endomitosis. Mutations and expression of only a limited number of oncogenes have been tested thus far. Whether the bcl-2 oncogene is involved in HD remains a matter of debate. Aneuploidy and non-random chromosomal abnormalities are the results of cytogenetic analyses of H-RS cells. However, no chromosomal marker specific for HD has yet been found. Thus, while studies of EBV involvement, growth factor production, oncogene expression and chromosomal abnormalities contributed a fair amount of new data on the nature of H-RS cells, only immunophenotyping and genotyping provided some indication of the cellular derivation: an activated lymphoid cell that possibly expresses oncogenes, that probably is infected with EBV, that most likely produces cytokines, that certainly has multiple karyotypic abnormalities.

Paraffin section immunohistochemistry in the diagnosis of Hodgkin's disease and anaplastic large cell (CD30+) lymphomas

Morphological and immunohistological studies were carried out on a series of 137 lymphomas including CD30+ anaplastic large cell (ALC) lymphomas (48 cases) and non-lymphocyte predominant Hodgkin's disease (HD) (89 cases), with the aim of assessing in situ expression of a combination of antibodies including anti-CD30/BerH2, epithelial membrane antigen (EMA), CD15 and CD45, in addition to other monoclonal antibodies suitable for paraffin tissues. A greater proportion of cases of ALC lymphomas than of HD exhibited positivity for CD45 (91.7% vs 17.6%), EMA (56.2% vs 4.5%), CD43 (53.6% vs 13.1%) and CD45RO (39.5% vs 3.5%), whereas Reed-Sternberg (RS) cells in HD most frequently expressed CD15 (93.2% vs 20.8%) antigen. Moreover, in 35 of 48 (72.9%) ALC lymphomas tumour cells expressed the CD30+, CD45+, CD15-, EMA- or + phenotypic profile, while in the same percentage (62/85) of HD cases RS cells were found to express the CD30+, CD45-, CD15+, EMA- profile. This study suggests that the differential expression of CD45, EMA, and CD15 may be used in the separation of ALC lymphomas and HD. However, co-expression of CD30, CD45 and CD15 antigens by RS cells in HD (14/85 cases, 16.5% in this series) and by tumour cells in ALC lymphomas (9/48 cases, 18.7% in this series) may be encountered in a non-negligible fraction of cases.

"Lipoleiomyoma with metaplastic cartilage" (benign mesenchymoma) of the uterine cervix

Benign mesenchymoma (BM) is an uncommon tumor containing two or more differentiated mesenchymal elements in addition to fibrous tissue. A case of BM of the uterine cervix in a 51-year-old woman is reported. This tumor, which we designated "lipoleiomyoma with metaplastic cartilage" because of its morphological features, apparently represents the first documented example of BM of the cervix.

Vimentin expression by Reed-Sternberg cells in Hodgkin's disease

The expression of vimentin in Reed-Sternberg cells in 61 samples of Hodgkin's disease (HD) was examined using an avidin-biotin-peroxidase complex technique. Forty biopsies (66%) expressed vimentin, and expression was seen in all subtypes of HD. No immunophenotypic differences between vimentin-positive and vimentin-negative cases were noted. The significance of such expression is unclear, but may be related to the alterations in growth and differentiation that are typical of neoplastic cells.

A clinicopathologic study of lymphoid neoplasias associated with human immunodeficiency virus infection in Italy

The clinicopathologic features of 45 human immunodeficiency virus (HIV)-infected patients (mainly intravenous drug users [IVDU]) with lymphoid neoplasias seen from September 1984 through July 1990 at an Italian cancer center are reviewed. Thirty-five had systemic non-Hodgkin's lymphoma (NHL), and ten had Hodgkin's disease (HD). Histologically, 27 NHL cases were intermediate grade (five cases) or high grade (22 cases, 14 of the small noncleaved cell type), according to the Working Formulation. Eight NHL cases, including four anaplastic large cell (ALC) BerH2 (CD30)-positive lymphomas, were in the miscellaneous group. Immunohistologic and/or gene rearrangement analysis showed the B-cell origin of 20 of the 24 NHL cases studied. At presentation, 71% of NHL patients had advanced stages (Stage III or IV), and 85% had extranodal disease (predominantly gastrointestinal tract and marrow). Of the 23 patients evaluable for treatment, only seven had a complete clinical response after lymphoma therapy; the median survival of 34 evaluable patients was 22 months after the diagnosis of NHL. Fifteen patients died; most deaths were attributable to progressive lymphoma and opportunistic infections. As with NHL, advanced disease, extranodal involvement, aggressive histologic findings, and poor response to therapy were also observed in patients with HD. This study shows that lymphoid neoplasias occurring in Italian IVDU with HIV infection and those previously reported in North American homosexual men with HIV infection share similar clinicopathologic features. However, some features such as the absence of history of Kaposi's sarcoma at diagnosis, the lack of detection of primary brain and rectal NHL, and the occurrence of B-cell ALC BerH2 (CD30)-positive NHL were observed uniquely in this series of patients.