EBV and Lymphomagenesis

The clinical significance of Epstein–Barr virus (EBV) cannot be understated. Not only does it infect approximately 90% of the world’s population, but it is also associated with numerous pathologies. Diseases linked to this virus include hematologic malignancies such as diffuse large B-cell lymphoma, Hodgkin lymphoma, Burkitt lymphoma, primary CNS lymphoma, and NK/T-cell lymphoma, epithelial malignancies such as nasopharyngeal carcinoma and gastric cancer, autoimmune diseases such as multiple sclerosis, Graves’ disease, and lupus. While treatment for these disease states is ever evolving, much work remains to more fully elucidate the relationship between EBV, its associated disease states, and their treatments. This paper begins with an overview of EBV latency and latency-associated proteins. It will then review EBV’s contributions to select hematologic malignancies with a focus on the contribution of latent proteins as well as their associated management.

T-cell-derived Hodgkin lymphoma has motility characteristics intermediate between Hodgkin and anaplastic large cell lymphoma

Classic Hodgkin lymphoma (cHL) is usually characterized by a low tumour cell content, derived from crippled germinal centre B cells. Rare cases have been described in which the tumour cells show clonal T-cell receptor rearrangements. From a clinicopathological perspective, it is unclear if these cases should be classified as cHL or anaplastic large T-cell lymphoma (ALCL). Since we recently observed differences in the motility of ALCL and cHL tumour cells, here, we aimed to obtain a better understanding of T-cell-derived cHL by investigating their global proteomic profiles and their motility. In a proteomics analysis, when only motility-associated proteins were regarded, T-cell-derived cHL cell lines showed the highest similarity to ALK- ALCL cell lines. In contrast, T-cell-derived cHL cell lines presented a very low overall motility, similar to that observed in conventional cHL. Whereas all ALCL cell lines, as well as T-cell-derived cHL, predominantly presented an amoeboid migration pattern with uropod at the rear, conventional cHL never presented with uropods. The migration of ALCL cell lines was strongly impaired upon application of different inhibitors. This effect was less pronounced in cHL cell lines and almost invisible in T-cell-derived cHL. In summary, our cell line-derived data suggest that based on proteomics and migration behaviour, T-cell-derived cHL is a neoplasm that shares features with both cHL and ALCL and is not an ALCL with low tumour cell content. Complementary clinical studies on this lymphoma are warranted.

CD30 Differential Staining is Useful in Classifying Lymphomas Intermediate between Hodgkin's Disease and Anaplastic Large Cell (Ki1) Lymphoma

AIMS AND BACKGROUND

The authors analyzed the BerH2 reactivity patterns of the tumor cells in 23 Hodgkin's lymphomas (HD), in 13 CD30+ anaplastic large cell (Ki1) lymphomas (ALCL), in two HD with transition to secondary CD30+ ALCL, and in six additional lymphomas intermediate between HD and ALCL.

METHODS

Paraffin blocks of formalin-fixed biopsies were immunostained. Immunostaining was modified by pronase digestion and by microwave assistance.

RESULTS

Hodgkin-Reed-Sternberg (HRS) cells of all 23 Hodgkin's lymphomas were reactive for BerH2, but the reactivity patterns differed: after pronase digestion, HRS cells of 17/23 Hodgkin's lymphomas showed exclusively or at least predominantly cytoplasmic BerH2 reactivity, whereas only four Hodgkin's lymphomas presented with prominent membrane-bound positivity. Microwave processing in 16/23 Hodgkin's lymphomas induced membrane-bound BerH2 positivity in the HRS cells; a minority of five cases retained the distinct cytoplasmic pattern. In contrast, 10/13 ALCLs were characterized by membranous reactions, independent of whether pronase or microwave pretreatment had been applied. The CD30+ ALCLs secondary to HD also showed a tendency towards membranous positivity more than did the antecedent Hodgkin's lymphomas. In the HD/ALCL borderline group, 3/6 cases revealed cytoplasmic BerH2 patterns after pronase digestion and thus were more closely related to HD, whereas 2/6 cases reacted with membranous positivity as did the genuine ALCLs of our series.

CONCLUSIONS

We conclude from these findings that the above modifications in CD30 immunostaining can be helpful in the characterization of lymphomas that constitute a continuous histomorphological as well as phenotypical spectrum between HD and ALCL.

Soluble CD27 induces IgG production through activation of antigen-primed B cells

OBJECTIVES

High levels of soluble CD27 (sCD27), a marker of immune activation, are found in several infectious [including human immunodeficiency virus type-I (HIV-1)] and autoimmune diseases; however, a direct biological effect of sCD27 on B cells has not been established. The aim of this study was to investigate whether sCD27, by binding to CD70, can induce immunoglobulin G (IgG) production from B cells.

METHODS

B cells from healthy and HIV-1-infected individuals were cultured with recombinant human sCD27 (rhsCD27), and IgG production was measured. The role of rhsCD27 in inducing the expression of transcription factors involved in plasma cell differentiation was evaluated. Furthermore, we investigated the impact of different cytokines on the modulation of CD70 expression on B cells and the relationship between levels of IgG and sCD27 in serum from healthy and HIV-1-infected individuals.

RESULTS

We demonstrated that rhsCD27 induced IgG production from antigen-primed (CD27+) B cells. This effect was mediated by rhsCD27 binding to CD70 on B cells leading to activation of Blimp-1 and XBP-1, transcription factors associated with plasma cell differentiation. We found a significant correlation between levels of serum sCD27 and IgG in HIV-1-infected individuals and healthy controls.

CONCLUSIONS

sCD27 may act to enhance immunoglobulin production and differentiation of activated memory or recently antigen-experienced B cells, thus providing an activation signal to antigen-experienced B cells. This mechanism may operate during autoimmune and chronic infectious diseases, situations in which continuous immune activation leads to upregulation of CD70 expression and increased sCD27 cleavage.

Proliferation response of leukemic cells to CD70 ligation oscillates with recurrent remission and relapse in a low-grade lymphoma

Interactions of the TNF-related cell surface ligand CD70 with its receptor CD27 provide a costimulatory signal in B and T cell activation. Functional CD70-CD27 interactions could contribute to lymphoma and leukemia progression. This possibility was studied using DNA microarrays on a unique case of low-grade lymphoma/leukemia characterized by recurrent cycles of acute leukemic phase alternating with spontaneous remission. Upon induction of the acute phase expression of CD70 and CD27 in the leukemic cells increased 38- and 25-fold, respectively. Coexpression of membrane CD70 and CD27 on the leukemic (CD5+CD19+) cells was maximal 2-3 days following initiation of the attack. Soluble CD27 in the patient's serum was elevated during remission and further increased in the attack. Functional tests showed that neither anti-CD70 nor anti-CD27 Abs affect the rate of apoptosis. However, the anti-CD70 Ab specifically enhanced proliferation of the remission phase leukemic cells, whereas proliferation of the acute-phase counterparts that express higher level of membrane CD70 was unaffected. Hence, in this lymphoma/leukemia, membrane CD70 is presented on the leukemic cells in a responsive state during the remission and a nonresponsive state during the attack. Presumably, CD70 in its responsive state provides a costimulatory receptor for initiating the next acute phase while its nonresponsive state enables the remission.

Immunoreactivity of CD99 in non-Hodgkin's lymphoma: unexpected frequent expression in ALK-positive anaplastic large cell lymphoma

To verify the spectrum of CD99-expressing lymphoid malignancy, an immunohistochemical study for CD99 was carried out in 182 cases of non-Hodgkin's lymphoma, including 21 lymphoblastic lymphomas, 11 small lymphocytic lymphomas, 9 mantle cell lymphomas, 12 follicular lymphomas, 37 diffuse large B cell lymphomas, 18 Burkitt's lymphomas, 28 NK/T-cell lymphomas, 8 angioimmunoblastic T-cell lymphomas, 23 peripheral T-cell lymphomas, unspecified, and 15 systemic anaplastic large cell lymphomas. CD99 was positive in all T-lymphoblastic lymphomas and in 60% of B-lymphoblastic lymphomas. Majority of T and NK cell lymphomas were negative for CD99, except anaplastic large cell lymphomas (ALCLs). Eight of 15 cases (54%) of ALCLs reacted with anti CD99 antibody. Seven of 10 (70%) ALK positive ALCLs expressed CD99, whereas only 1 of 5 (20%) ALK negative ALCLs were positive. Of the mature B-cell lymphomas, 5.4% (2/37) of diffuse large B cell lymphomas and 11.1% (2/18) of Burkitt's lymphomas expressed CD99. In conclusion, CD99 is infrequently expressed in mature B and T cell lymphomas, except ALK-positive ALCL. High expression of CD99 in ALK-positive ALCL is unexpected finding and its biologic and clinical significances have yet to be clarified.

Signaling through CD70 regulates B cell activation and IgG production

CD70, the cellular ligand of the TNF receptor family member CD27, is expressed transiently on activated T and B cells and constitutively on a subset of B cell chronic lymphocytic leukemia and large B cell lymphomas. In the present study, we used B cells constitutively expressing CD70 to study the functional consequences of signaling through CD70. In vitro, CD70 ligation with anti-CD70 mAbs strongly supported proliferation and cell cycle entry of B cells submitogenically stimulated with either anti-CD40 mAb, LPS, or IL-4. In this process, the cell surface receptors CD25, CD44, CD69, CD95, and GL7 were up-regulated, whereas the expression of CD21, CD62L, surface IgM (sIgM), and sIgD was decreased. Addition of CD70 mAb to low dose LPS-stimulated CD70-positive B cells strongly diminished IgG secretion and enhanced production of IgM. Signaling through CD70 on B cells was dependent on the initiation of both PI3K and MEK pathways. In vivo exposure to either CD70 mAb or the CD70 counterreceptor CD27 down-regulated CD62L and sIgM on CD70-positive B cells. CD70 signaling during T cell-dependent immune responses also decreased IgG-specific Ab titers. Together, the in vitro and in vivo data demonstrate that CD70 has potent reverse signaling properties in B cells, initiating a signaling cascade that regulates expansion and differentiation.

A ligand-inducible epidermal growth factor receptor/anaplastic lymphoma kinase chimera promotes mitogenesis and transforming properties in 3T3 cells

Oncogenic rearrangements of the anaplastic lymphoma kinase (ALK) gene, encoding a receptor type tyrosine kinase, are frequently associated with anaplastic large cell lymphomas. Such rearrangements juxtapose the intracellular domain of ALK to 5'-end sequences belonging to different genes and create transforming fusion proteins. To understand how the oncogenic versions of ALK contribute to lymphomagenesis, it is important to analyze the biological effects and the biochemical properties of this receptor under controlled conditions of activation. To this aim, we constructed chimeric receptor molecules in which the extracellular domain of the ALK kinase is replaced by the extracellular, ligand-binding domain of the epidermal growth factor receptor (EGFR). Upon transfection in NIH 3T3 fibroblasts, the EGFR/ALK chimera was correctly synthesized and transported to the cell surface, where it was fully functional in forming high versus low affinity EGF-binding sites and transducing an EGF-dependent signal intracellularly. Overexpression of the EGFR/ALK chimera in NIH 3T3 was sufficient to induce the malignant phenotype; the appearance of the transformed phenotype was, however, conditionally dependent on the administration of EGF. Moreover, the EGFR/ALK chimera was significantly more active in inducing transformation and DNA synthesis than the wild type EGFR when either was expressed at similar levels in NIH 3T3 cells. Comparative analysis of the biochemical pathways implicated in the transduction of mitogenic signals did not show any increased ability of the EGFR/ALK to phosphorylate PLC-gamma and MAPK compared with the EGFR. On the contrary, EGFR/ALK showed to have a consistently greater effect on phosphatidylinositol 3-kinase activity compared with the EGFR, indicating that this enzyme plays a major role in mediating the mitogenic effects of ALK in NIH 3T3 cells.

Pathologic and clinical features of 77 Hodgkin's lymphoma patients treated in a lymphoma protocol (LNH87): a GELA study

Between 1987 and 1993, 77 of 2855 lymphomas included in the LNH87 protocol of the GELA as non-Hodgkin lymphoma (NHL) and reviewed by a panel of pathologists had a diagnosis changed to Hodgkin lymphoma (HL). Some of these lymphomas had been initially interpreted as anaplastic large-cell lymphoma Hodgkin-like (ALCL-HL subtype). The purpose of this study was to analyze the histologic pitfalls initially encountered, to define more clearly the diagnostic criteria of lymphomas placed in the gray zone around HL, and to follow the survival of these 77 patients affected with HL and initially treated with NHL regimens. The 77 cases of HL were reviewed by three hematopathologists and immunostained with a large panel of antibodies, including CD30, CD15, CD3, CD20, CD45, CD43, LMP-1, EMA, BNH-9, TiA1, and ALK1. Each case was classified according to the Lukes-Rye system and the British National Lymphoma Investigation (BNLI) grading. The initial clinical presentation of patients was analyzed, and the overall and event-free survival rates of the 77 patients were estimated. Among the 77 HLs, 46 were misinterpreted as NHL by primary individual pathologists (12 as ALCL, 8 as ALCL-HL, 12 as peripheral T-cell lymphoma (PTCL), 6 as B-cell lymphoma, and 8 as unclassifiable NHL). The other 31 cases had been first considered by the panel as consistent with ALCL-HL (n = 18) or with PTCL (n = 13) and were changed later in view of an immunophenotype concordant with HL. Fifty-five percent of the patients completed the full NHL treatment. The 5-year event-free and overall survival rates were 54% and 77%, respectively. The current results indicate that lymphomas initially called ALCL-HL should not be regarded as a variant of ALCL, but as HL. The clinical consequences of misdiagnoses seem to be a lower event-free survival rate compared with that of classical HL, probably because of more relapses of initially inappropriately treated HL.

Nucleophosmin–anaplastic lymphoma kinase associated with anaplastic large-cell lymphoma activates the phosphatidylinositol 3-kinase/Akt antiapoptotic signaling pathway

More than half of anaplastic large-cell lymphomas (ALCLs) have a chromosomal translocation t(2;5) that leads to the expression of a hybrid protein composed of the nucleolar phosphoprotein nucleophosmin (NPM) and the anaplastic lymphoma kinase (ALK) that exhibits an unregulated tyrosine kinase activity. We have previously identified PLC-γ as a crucial downstream signaling molecule of NPM-ALK that contributes to its mitogenic potential. Here, we show that NPM-ALK recruits the C-terminal SH2 domain of the phosphatidylinositol 3-kinase (PI 3kinase) p85 subunit. PI 3-kinase assays revealed that the kinase is activated by NPM-ALK in vivo, in turn activating PKB/Akt in NPM-ALK–expressing cells. The use of 2 specific PI 3-kinase inhibitors, wortmannin and LY294002, demonstrated the requirement of PI 3-kinase for the growth of NPM-ALK–transformed cell lines, as well as a cell line established from a patient with ALCL. Primary murine bone marrow retrovirally transduced with NPM-ALK showed a transformed phenotype that was reversible on treatment with PI 3-kinase inhibitors. Flow cytometric analysis revealed that wortmannin-treated NPM-ALK–transformed cell lines underwent apoptosis. Furthermore, apoptosis induced by overexpression of the proapoptotic molecule Bad could be partially blocked by the overexpression of NPM-ALK. Thus, NPM-ALK activates the antiapoptotic PI 3-kinase/Akt pathway, which likely contributes to the molecular pathogenesis of ALCL.

Nucleophosmin–anaplastic lymphoma kinase associated with anaplastic large-cell lymphoma activates the phosphatidylinositol 3-kinase/Akt antiapoptotic signaling pathway

More than half of anaplastic large-cell lymphomas (ALCLs) have a chromosomal translocation t(2;5) that leads to the expression of a hybrid protein composed of the nucleolar phosphoprotein nucleophosmin (NPM) and the anaplastic lymphoma kinase (ALK) that exhibits an unregulated tyrosine kinase activity. We have previously identified PLC-γ as a crucial downstream signaling molecule of NPM-ALK that contributes to its mitogenic potential. Here, we show that NPM-ALK recruits the C-terminal SH2 domain of the phosphatidylinositol 3-kinase (PI 3kinase) p85 subunit. PI 3-kinase assays revealed that the kinase is activated by NPM-ALK in vivo, in turn activating PKB/Akt in NPM-ALK–expressing cells. The use of 2 specific PI 3-kinase inhibitors, wortmannin and LY294002, demonstrated the requirement of PI 3-kinase for the growth of NPM-ALK–transformed cell lines, as well as a cell line established from a patient with ALCL. Primary murine bone marrow retrovirally transduced with NPM-ALK showed a transformed phenotype that was reversible on treatment with PI 3-kinase inhibitors. Flow cytometric analysis revealed that wortmannin-treated NPM-ALK–transformed cell lines underwent apoptosis. Furthermore, apoptosis induced by overexpression of the proapoptotic molecule Bad could be partially blocked by the overexpression of NPM-ALK. Thus, NPM-ALK activates the antiapoptotic PI 3-kinase/Akt pathway, which likely contributes to the molecular pathogenesis of ALCL.

CD30+ anaplastic large cell lymphoma: a review of its histopathologic, genetic, and clinical features

Anaplastic large cell lymphoma (ALCL) represents a generally recognized group of large cell lymphomas. Defining features consist of a proliferation of predominantly large lymphoid cells with strong expression of the cytokine receptor CD30 and a characteristic growth pattern. With the use of molecular and clinical criteria, 3 entities of ALCL have been identified: primary systemic anaplastic lymphoma kinase (ALK)+ ALCL, primary systemic ALK− ALCL, and primary cutaneous ALCL. ALK expression is caused by chromosomal translocations, most commonly t(2;5). ALK+ ALCL predominantly affects young male patients and, if treated with chemotherapy, has a favorable prognosis. It shows a broad morphologic spectrum, with the “common type,” the small cell variant, and the lymphohistiocytic variant being most commonly observed. The knowledge of the existence of these variants is essential in establishing a correct diagnosis. ALK− ALCL occurs in older patients, affecting both genders equally and having an unfavorable prognosis. The morphology and the immunophenotype of primary cutaneous ALCL show an overlap with that of lymphomatoid papulosis. Both diseases have an excellent prognosis, and secondary systemic dissemination is only rarely observed. The described ALCL entities usually derive from cytotoxic T cells. In contrast, large B-cell lymphomas with anaplastic morphology are believed to represent not a separate entity but a morphologic variant of diffuse large B-cell lymphoma. Malignant lymphomas with morphologic features of both Hodgkin disease and ALCL have formerly been classified as Hodgkin-like ALCL . Recent immunohistologic studies, however, suggest that ALCLs Hodgkin-like represent either cases of tumor cell–rich classic Hodgkin disease or (less commonly) ALK+ ALCL or ALK− ALCL.

Pathobiology of NPM-ALK and variant fusion genes in anaplastic large cell lymphoma and other lymphomas

Despite its clinical and histological heterogeneity, anaplastic large cell lymphoma (ALCL) is now a well-recognized clinicopathological entity accounting for 2% of all adult non-Hodgkin's lymphomas (NHL) and about 13% of pediatric NHL. Immunophenotypically, ALCL are of T cell (predominantly) or Null cell type; by definition, cases expressing B cell antigens are officially not included in this entity. The translocation (2;5)(p23;q35) is a recurring abnormality in ALCL; 46% of the ALCL patients bear this signature translocation. This translocation creates a fusion gene composed of nucleophosmin (NPM) and a novel receptor tyrosine kinase gene, named anaplastic lymphoma kinase (ALK). The NPM-ALK chimeric gene encodes a constitutively activated tyrosine kinase that has been shown to be a potent oncogene. The exact pathogenetic mechanisms leading to lymphomagenesis remain elusive; however, the synopsis of evidence obtained to date provides an outline of likely scenarios. Several t(2;5) variants have been described; in some instances, the breakpoints have been cloned and the genes forming a new fusion gene with ALK have been identified: ATIC-ALK, TFG-ALK and TPM3-ALK. Cloning the translocation breakpoint and identifying the ALK and NPM genes provided tools for screening material from patients with ALCL using various approaches at the chromosome, DNA, RNA, or protein level: positive signals in the reverse transcriptase-polymerase chain reaction (RT-PCR) and the immunostaining with anti-ALK monoclonal antibodies (McAb) serve as the most convenient tests for detection of the t(2;5) NPM-ALK since the fusion gene and ALK protein expression do not occur in normal or reactive lymphoid tissue. The wide range of NPM-ALK positivity reported in different series appears to be dependent on the inclusion and selection criteria of the ALCL cases studied. Overall, however, 43% of ALCL cases were NPM-ALK+ (83% of pediatric ALCL vs 31% of adult ALCL). Occasional non-ALCL B cell lymphomas (4%) with diffuse large cell and immunoblastic histology and Hodgkin's disease cases (3%) were NPM-ALK-, but these data are questionable. The aggregate results indicate that, in contrast to primary nodal (systemic) ALCL, the t(2;5) may be present in only 10-20% of primary cutaneous ALCL and rarely, if at all, in lymphomatoid papulosis, a potential precursor lesion; however, these 10-20% positive cases were not confirmed by anti-ALK McAb immunostaining and may represent an overestimate. Positivity for NPM-ALK is associated to various degrees with the following parameters: 44% and 45% of ALCL cases with T cell and Null cell immunophenotype, respectively, are positive, whereas only 8% of cases with a B cell immunoprofile are positive; the mean age of positive patients is significantly younger than that of negative patients; positive cases carry a better overall prognosis (but not in all studies). Recently, the homogenous category of ALK lymphoma ('ALKoma') has emerged as a distinct pathological entity within the heterogenous group of ALCL. The fact that patients with ALK lymphomas experience significantly better overall survival than ALK- ALCL demonstrates further that analysis of ALK expression has important prognostic implications. The term ALK lymphoma signifies a switch in the use of the diagnostic criteria: cases are selected on the basis of a genetic abnormality (the ALK rearrangement), instead of the review of morphological or immunophenotypical features which are clearly more prone to disagreement and controversy. Since its initial description in 1985 ALCL has become one of the best characterized lymphoma entities.

Autologous stem cell transplantation for anaplastic large-cell lymphomas: results of a prospective trial

Autologous stem cell transplantation (ASCT) in the front line treatment of non-Hodgkin's lymphoma (NHL) remains controversial. Anaplastic large-cell lymphoma (ALCL) is known to have its own clinical and biological features. The outcome of ALCL patients treated with high-dose chemotherapy and ASCT as part of their first-line therapy was analysed in 202 intermediate or high-grade NHL patients in a prospective randomized trial. First-line chemotherapy comprised two alternating anthracycline-containing regimens. Responding patients were autografted after a BEAM (BCNU, cytarabine, etoposide and melphalan) regimen. Patients with bulky or residual masses were irradiated. Fifteen patients with ALCL were identified by morphological and immunological features (CD30 was expressed in 14 out of 15 patients, three patients expressed B-cell markers, five patients expressed T-cell markers and seven patients did not express cell markers). Anaplastic lymphoma kinase (ALK) expression was confirmed in seven cases. The median age was 39 years with a predominant male sex ratio (2.75). Thirteen patients were stage >/= III and six presented with two or more adverse prognostic factors. According to the international age-adjusted prognostic index, the expected complete remission (CR), event-free survival (EFS) and overall survival (OS) rates were 69%, 71% and 69%. Two deaths were observed (one due to interstitial pneumonitis, one due to pulmonary carcinoma). All patients entered CR, no relapse occurred and EFS and survival reached 87% with a follow-up of more than 5 years. These results differ significantly from those observed in the other 176 lymphoma patients: event-free survival was only 53 +/- 5% and OS reached 60 +/- 4% with a median follow-up of 56 months (P = 0.006). Intensified chemotherapy with autologous stem cell support appeared effective in the treatment of ALCL, offering patients the real chance of a cure.

Primary anaplastic large cell lymphoma of the adrenal gland

Primary adrenal lymphomas are rare. Most reported cases are of B-cell phenotype and follow an aggressive clinical course. We report a case of primary anaplastic large cell, CD30+ adrenal lymphoma developing in a 62-year-old woman. The patient presented with fatigue and vague right upper quadrant pressure. Computed tomography revealed bilateral adrenal masses. A right adrenalectomy was performed. Histologic evaluation showed islands of large atypical cells surrounded by eosinophilic acellular material. The tumor cells stained positive for CD45, CD45RO, CD43, and CD30. Epstein-Barr virus genome was identified in tumor cells using in situ hybridization. The patient was treated with chemotherapy and a 23-month follow-up examination showed no change in the size of the opposite adrenal gland and no other evidence of lymphoma.

Overview of the role of molecular methods in the diagnosis of malignant lymphomas

OBJECTIVE

To review the role of molecular genetics in the diagnosis of malignant lymphomas.

DATA SOURCES AND STUDY SELECTION

Primary research studies and reviews published in the English literature that focus on molecular genetics and malignant lymphoma, in particular, clonality, chromosomal translocations, tumor suppressor genes, and Hodgkin disease.

DATA EXTRACTION AND SYNTHESIS

Molecular genetics has an important role in the assessment of malignant lymphomas. Clonality, detected by Southern blot analysis or the polymerase chain reaction, is helpful for establishing the diagnosis of lymphoma in lesions with ambiguous morphologic and immunophenotypic findings. Southern blot analysis is the "gold standard" for clonality assessment, but the process is labor-intensive and time-consuming. Polymerase chain reaction analysis is more convenient, but a potentially significant false-negative rate exists in the analysis of some antigen receptor genes as a result of using consensus primers and the process of somatic hypermutation. Chromosomal translocations, which result in oncogene activation, occur in many types of B- and T-cell lymphomas, and their detection is helpful in classification as well as in establishing a diagnosis of malignancy. Gene rearrangements and chromosomal translocations also can be used to monitor minimal residual disease. Tumor suppressor genes, although their analysis is relatively less useful for diagnosis, are involved in both pathogenesis and tumor progression and will be more important diagnostically as this field continues to expand. Molecular genetic analysis has played a major role in improving our understanding of Hodgkin disease.

CONCLUSIONS

Molecular genetic tests are currently important ancillary tools for the diagnosis and classification of malignant lymphomas, and their role is likely to increase in the future.

The therapy of primary adult systemic CD30-positive anaplastic large cell lymphoma: results of 40 cases treated in a single center

The outcome of a series of adult patients, affected by primary systemic CD30-positive anaplastic large cell lymphoma (ALCL), treated with a sequential intensive therapeutic program, has been analyzed and all data available in the literature have been reviewed. Forty consecutive, unselected patients with ALCL were treated with the F-MACHOP regimen, followed by radiotherapy (RT) for residual mediastinal disease (15 cases) and by autologous stem cell transplantation (ASCT) conditioned with BAVC (29 cases). Eighty-nine percent (32/36) of the patients younger than 60 years were eligible for completing the sequential treatment. Since then, 3 patients in CR refused ASCT, 1 was excluded for cardiac toxicity and 3 progressed and died of disease. Thus, 29 have been so far submitted to the transplant procedure. CR and PR rates were 40% and 45% respectively after CHT; 52.5% and 35% after RT; 80% and 5% after ASCT, with 78% of patients transplanted in PR convertin to a CR. Actuarial overall survival is 85% at 48.5 months (93% at 66 months for the 29 transplanted patients) and disease free survival is 100% at 54 and 64 months respectively, with no relapses observed among patients who reached a CR. Considering our data and those of the literature, it can be concluded that although the role of ASCT in the therapy of ALCL must not be considered as definitive, its efficacy in converting PR into CR and in preventing relapses, suggests that a randomized trial comparing CHT alone vs CHT+ASCT should be undertaken.

Effect of material deprivation on Epstein-Barr virus infection in Hodgkin's disease in the West Midlands

We have used Townsend scores from postcode data to compare levels of material deprivation and Epstein-Barr virus (EBV)-positivity for 223 patients diagnosed with Hodgkin's disease (HD) in the period 1981-1997. The presence of EBV in HD tumours was determined using in situ hybridization to target the abundantly expressed EBV early RNAs. EBV was detected in the malignant Hodgkin and Reed-Sternberg cells in 47/223 HD cases (21%). There was found to be a tendency for higher Townsend scores (indicative of higher levels of material deprivation) in EBV-positive HD patients, but this association was not statistically significant. When various subgroups of patients from the study were examined separately the indication of higher Townsend scores in EBV-positive patients was found to be more marked for patients with mixed cellularity disease (P = 0.09) and for females (P = 0.03). The results of this study suggest that differences in the level of material deprivation are important in determining the likelihood of EBV-positive HD in the UK, particularly for certain subgroups of patients. It is not known what specific socioeconomic factors are responsible for these differences, although alterations in the timing or rate of primary EBV infection, or decline in the level of EBV-specific immunity, may be important.

Unilateral proptosis in an immunocompetent man as the initial clinical manifestation of systemic Hodgkin disease

OBJECTIVE

Orbital involvement in Hodgkin disease (HD) is rare. Previously reported cases of HD in patients without the acquired immunodeficiency syndrome have been diagnosed late in the course of established systemic disease. The authors describe an immunocompetent man with orbital infiltration as the initial manifestation of systemic HD.

DESIGN

Case report.

PARTICIPANTS

A 47-year-old man with acute progressive, painless proptosis of the left eye is described.

INTERVENTION

A well-defined, homogeneous soft tissue mass of the superior left orbit was evident on computed tomography, and an incisional biopsy of the nontender mass was performed.

RESULTS

The histopathologic findings were characteristic of HD. Systemic investigations showed clinical stage 3A HD. Ten months after completion of hybrid chemotherapy, the patient remained in complete remission from his HD.

CONCLUSION

Hodgkin disease presenting initially in the orbit of a patient with the acquired immunodeficiency syndrome has been described previously. The patient presented in this report is the first case of HD in the recent English literature with the initial manifestation in the orbit of an otherwise immunocompetent patient.

Transformation of the small cell variant Ki-1+ lymphoma to anaplastic large cell lymphoma: pathologic and clinical features

The disease spectrum of anaplastic large cell lymphoma (ALCL) includes a biologically aggressive small cell variant (SCV). The SCV may progress to ALCL, but little is known about the transformation process and its significance. The goals of this study were (1) to identify the clinical and pathologic features that characterize ALCL arising in SCV and (2) to determine whether some cases with ALCL histologic appearance at the outset arose from an SCV. Seventeen SCV were reviewed, and four cases (24%) transformed to ALCL as shown by subsequent biopsy. The ALCLs were predominantly monomorphic (3 cases) rather than pleomorphic (1 case). Residual SCV was detected at transformation in 3 of 4 cases. Twenty-one de novo T-cell ALCLs were reviewed for an SCV component; such a component was identified in two ALCLs with monomorphic features, suggesting a preceding SCV phase. There was no change in the immunophenotype between the SCV and ALCL, all marking as EMA+ T cells. Expression of p80 was detected in 3 of 4 (75%) SCV with transformation and 10 of 12 (77%) SCV without transformation. Chromosomal abnormalities involving the sex chromosomes and 6, 7, 9, and 15, in addition to the characteristic t(2;5)(p23;q35), were present in 2 cases at transformation. Times to transformation ranged from 1 to 146 months (mean: 63 months) after diagnosis. Transformation to ALCL signaled a rapid clinical course, with 75% of patients dying in less than a year; one patient remains alive at 15 months. In summary, some ALCLs, particularly those with monomorphic features, arise from an SCV. Transformation to ALCL signals a rapid course, with death occurring in less than a year in most cases. Necrosis in the SCV may be predictive of transformation. Chromosomal abnormalities in addition to the t(2;5)(p23;q35) are present at transformation, suggesting that multiple genetic alterations are involved in disease progression.

Nucleophosmin-anaplastic lymphoma kinase of large-cell anaplastic lymphoma is a constitutively active tyrosine kinase that utilizes phospholipase C-gamma to mediate its mitogenicity

Large-cell anaplastic lymphoma is a subtype of non-Hodgkin's lymphoma characterized by the expression of CD30. More than half of these lymphomas have a chromosomal translocation, t(2;5), that leads to the expression of a hybrid protein comprised of the nucleolar phosphoprotein nucleophosmin (NPM) and the anaplastic lymphoma kinase (ALK). Here we show that transfection of the constitutively active tyrosine kinase NPM-ALK into Ba/F3 and Rat-1 cells leads to a transformed phenotype. Oncogenic tyrosine kinases transform cells by activating the mitogenic signal transduction pathways, e.g., by binding and activating SH2-containing signaling molecules. We found that NPM-ALK binds most specifically to the SH2 domains of phospholipase C-gamma (PLC-gamma) in vitro. Furthermore, we showed complex formation of NPM-ALK and PLC-gamma in vivo by coimmunoprecipitation experiments in large-cell anaplastic lymphoma cells. This complex formation leads to the tyrosine phosphorylation and activation of PLC-gamma, which can be corroborated by enhanced production of inositol phosphates (IPs) in NPM-ALK-expressing cells. By phosphopeptide competition experiments, we were able to identify the tyrosine residue on NPM-ALK responsible for interaction with PLC-gamma as Y664. Using site-directed mutagenesis, we constructed a comprehensive panel of tyrosine-to-phenylalanine NPM-ALK mutants, including NPM-ALK(Y664F). NPM-ALK(Y664F), when transfected into Ba/F3 cells, no longer forms complexes with PLC-gamma or leads to PLC-gamma phosphorylation and activation, as confirmed by low IP levels in these cells. Most interestingly, Ba/F3 and Rat-1 cells expressing NPM-ALK(Y664F) also show a biological phenotype in that they are not stably transformed. Overexpression of PLC-gamma can partially rescue the proliferative response of Ba/F3 cells to the NPM-ALK(Y664F) mutant. Thus, PLC-gamma is an important downstream target of NPM-ALK that contributes to its mitogenic activity and is likely to be important in the molecular pathogenesis of large-cell anaplastic lymphomas.

Anaplastic large cell lymphoma of the spleen

A case is presented of CD30+ anaplastic large cell lymphoma of the spleen. The patient, a 61 year old woman with a history of chronic lymphocytic leukemia (CLL) was seen for the sudden development of splenomegaly with thrombocytopenia. A splenectomy was performed which showed massive replacement of the spleen by a population of large atypical lymphoid cells showing bizarre nuclear forms and multinucleated tumor cells reminiscent of Reed-Sternberg cells. Immunohistochemical studies showed strong membrane and dot-like paranuclear positivity in the majority of the atypical cells for CD30, with coexpression in many of the cells for CD15. Additionally, the cells also strongly reacted with CD3, UCHL-1, EMA and LCA. The present case illustrates an unusual variant of anaplastic (CD30+) large cell lymphoma sharing histologic and immunophenotypic features that overlap with those of Hodgkin's disease. The history in this patient of CLL with sudden development of splenomegaly raises the possibility of transformation of CLL into a high-grade lymphoma (Richter's syndrome). The possible pathogenetic implications of this phenomenon are discussed.

Genomic DNA amplification and the detection of t(2;5)(p23;q35) in lymphoid neoplasms

Anaplastic large cell lymphoma (ALCL) is an intermediate grade Non-Hodgkin's lymphoma (NHL) characterized by the frequent presence of the t(2;5)(p23;q35). This translocation fuses the nucleophosmin (NPM) gene on chromosome 5q35 to a protein kinase gene (Anaplastic Lymphoma Kinase, ALK) on chromosome 2p23. In order to determine the frequency of t(2;5) we used a DNA polymerase chain reaction (PCR) amplification using genomic DNA, 5'-primers derived from the NPM gene, and 3'-primers derived from the ALK gene. The presence of amplifiable DNA in the samples was established with PCR and oligonucleotide primers designed to amplify a 3,016 bp fragment from the beta-globin locus. The t(2;5) PCR assay was established using DNA isolated from three t(2;5)-positive ALCL cell lines. Its ability to amplify genomic DNA prepared for routine molecular diagnostic use was validated using archival DNA from four ALCL tumors known to be t(2;5)-positive. Its sensitivity was established by serially diluting t(2;5)-positive DNA in normal DNA: amplicons were generated in 100% of reactions diluted 10(4)-fold (6-8 cells per tube) and in 30% of those diluted 10(5)-fold (0.6-0.8 cells per tube.) We subsequently analyzed archival genomic DNA extracted from 38 ALCL, 77 NHLs, 37 Hodgkin's lymphomas, and 9 lymphomatoid papuloses. The t(2;5) was detected in 6 ALCLs (16%, 95% confidence intervals 6%-31%), but not in any other lymphoma, or in lymphomatoid papulosis. By using the published sequence of the fourth NPM intron that is involved in t(2;5) and by sequencing the individual tumor amplicons and also the normal ALK intron that is involved in t(2;5), we established that all breakpoints involve the same introns in the ALK and NPM loci. Detailed analysis demonstrated that each translocation generates a unique breakpoint sequence, and suggested that sequence homology between the ALK and NPM intron sequences may be involved in the translocation. We conclude that genomic DNA-PCR is useful for the detection of t(2;5) that in our patient population is restricted to ALCL and is not detectable in other NHL, Hodgkin's disease, or lymphomatoid papulosis. More work is needed to determine the prognostic significance of t(2;5), and to establish the utility of the genomic DNA PCR in monitoring minimal residual disease.

Primary Anaplastic Large-Cell Lymphoma in Adults: Clinical Presentation, Immunophenotype, and Outcome

Anaplastic, CD30+, large-cell lymphoma is now a well-recognized pathologic entity that accounts for 2% to 8% of all lymphomas. Recent progress has been made in the understanding of certain biologic features found in anaplastic large-cell lymphoma, but information about its clinical behavior, in comparison to other large-cell lymphomas, is limited. The pathologic review of a large multicenter study of the treatment of aggressive lymphoma identified 146 cases of anaplastic large-cell lymphoma (ALCL) on the basis of morphology and CD30 expression. We compared initial presentation, immunophenotype, and clinical outcome of these cases with those of the 1,695 nonanaplastic diffuse large-cell lymphomas (non-ALCL) included in the same trial. Patients with ALCL were more likely to be male (P = .018) and were younger (P < .0001) than those with non-ALCL. B symptoms were more frequent in ALCL (P = .006). Skin (P < .0001) and lung (P < .05) involvement was also more frequent in ALCL, but frequency of bone marrow involvement was identical (P = .5). Tumor cell phenotype was B in 56 cases (38%), T in 49 cases (34%), and null in 33 cases (22%). Response to chemotherapy (P = .001), event-free survival (P = .006), and overall survival (P = .0004) were better for ALCL than for non-ALCL. Multivariate analyses identified anaplastic character as an independent factor that predicted a longer survival. Tumor cell phenotype did not influence event-free survival (P = .72) or overall survival (P = .83). ALCL in adults is a clinicopathologic entity which, independent of its phenotypic characteristics, has a better outcome than other diffuse large-cell lymphomas.

Antibody cross-linking of the thymocyte-specific cell surface molecule CTX causes abnormal mitosis and multinucleation of tumor cells

The thymocyte-specific cell surface molecule CTX is a developmentally regulated type I transmembrane protein of the immunoglobulin superfamily which, in the amphibian Xenopus, is exclusively expressed by a large fraction of cortical thymocytes and by different cell lines derived from independent spontaneous thymic tumors. Antibody cross-linking of CTX in vitro inhibits the growth of tumor cells and causes morphological alterations. Cells divide abnormally, accumulate in the G2/M phase of the cell cycle, and become multinucleated. This demonstrates, for the first time, that multinucleation can be induced by specifically cross-linking a cell surface molecule.

Lack of correlation between EBV serology and presence of EBV in the Hodgkin and Reed-Sternberg cells of patients with Hodgkin's disease

Epstein-Barr virus (EBV) is detected in Hodgkin and Reed-Sternberg (HRS) cells in up to 50% of patients with Hodgkin's disease (HD). HD patients have been reported to express high serum titers against EBV antigens, even prior to the diagnosis of HD. Patients with high serum titers have a poorer prognosis. The aim of this study was to examine the relationship between the presence of EBV in HRS cells and the antibody titers reactive with different EBV antigens. Frozen serum and histopathological tissues were available from 107 untreated HD patients diagnosed between 1979 and 1991. The presence of EBV in the HRS cells was evaluated with immunohistochemistry directed against the LMP-1 antigen and/or with in situ hybridization of EBER-1. Analyses were performed of serum titers against early antigen (EA), diffuse (IgA and IgG) and restricted (IgG), virus-capsid antigen (VCA) (IgA and IgG), and EBV-encoded nuclear antigens (EBNA, EBNA 1, EBNA 2A, EBNA 2B, EBNA 6). EBV was detected in 27/107 (25%) tumor specimens, with a higher proportion in the MC group 8/13 (62%) (p < 0.01). IgG VCA and EBNA were detected in 99/107 (93%), evidence of a previous EBV infection. There were no significant relationships between antibody titers reactive with different EBV antigens and detectable EBV in HRS cells. Furthermore, there did not appear to be any relationship between EBV serology or the presence of EBV in HRS cells and clinical outcome. The role of EBV in the development of HD, especially its relationship to the immunological response, remains unclear.

Primary intestinal Hodgkin's disease complicating ileal Crohn's disease

An unusual primary intestinal lymphoma that occurred as a complication of ileal Crohn's disease is presented. Immunohistochemistry confirmed the light microscopic diagnosis of Hodgkin's disease (nodular sclerosing), and characterized a distinct mucosal nodule as a large-cell anaplastic non-Hodgkin's lymphoma. This unusual lymphoma developed while the patient was being treated with immunosuppressant medication. The present report is a reminder to clinicians of the possibility of occult lymphoma in ileal Crohn's disease.

IgH and TcR-gamma gene rearrangements identified in Hodgkin's disease by PCR demonstrate lack of correlation between genotype, phenotype, and Epstein-Barr virus status

Analysis of IgH and TcR-gamma genes using consensus primers identifying junctional regions of rearranged genes by polymerase chain reaction (PCR) was performed on tissues involved by Hodgkin's disease (HD) in 90 cases and was correlated with the immunophenotype of Hodgkin and Reed-Sternberg (HRS) cells and the presence of Epstein-Barr virus (EBV) within these cells. Clonal IgH gene rearrangements were found in 1/5 cases of lymphocyte predominance (LP) subtype and none was positive for EBV. In 85 cases of classic HD, no IgH or TcR-gamma gene rearrangements were found in 51 (60 per cent) cases. A similar percentage, but not the same cases, were of null (non-B, non-T) phenotype. Of 30 cases where a B phenotype was assigned to HRS cells, nine had IgH gene rearrangements, three had TcR-gamma gene rearrangements, and two had both genes rearranged. None of the five cases assigned to T phenotype of HRS cells showed rearrangement of TcR-gamma genes, but two cases showed rearranged IgH genes. Among 41 cases of null phenotype, ten had IgH gene rearrangements, five had TcR-gamma gene rearrangements, and three cases had both genes rearranged. Whereas EBV was detectable in HRS cells in 17/43 classic HD cases of assigned B phenotype, EBV was also detectable in 2/5 cases of assigned T phenotype and in 21 cases with the null phenotype. Furthermore, there was no correlation of EBV with the presence or lack or IgH or TCR-gamma gene rearrangements. Of the remainder, half (30 per cent) expressed antigens associated with lymphocytes without an appropriate genotype. The results confirm lymphocyte-lineage committed cells at the origin of HRS cells in 40 per cent of cases. Any hypothesis of a non-lymphocytic origin of HRS cells will require the inducibility of CD30 on candidate precursors and the methodology for probing genetic events in such cells to be addressed.

Sequential intensive treatment with the F-MACHOP regimen (+/- radiotherapy) and autologous stem cell transplantation for primary systemic CD30 (Ki-1)--positive anaplastic large cell lymphoma in adults

Most of the adult patients with primary systemic CD30 (Ki-1)-positive anaplastic large cell lymphoma (ALCL) reported in the literature have been treated with combination chemotherapy (CHT), with only an occasional patient being autotransplanted, mostly after relapse. Here we report a series of 19 patients treated at our Institution with a sequential intensive therapeutic program including CHT (the F-MACHOP regimen given for 6 cycles), radiotherapy (RT), and autologous stem cell transplantation (ASCT) after conditioning with the BAVC regimen. Eleven of 19 (58%) patients achieved a complete remission (CR) after CHT; 3 after RT and 4 after ASCT (1 patient is still not evaluable for response to ASCT). The actuarial overall survival is 100% at a median of 49 months from diagnosis and the actuarial disease free survival is 100% at a median of 41 months from the time CR was reached. These data suggest that ALCL can be successfully managed with a sequential intensive treatment that prevents early relapses and projects these patients as long-term survivors.

CD80, CD86 and CD40 provide accessory signals in a multiple-step T-cell activation model

In this review, a sequential multiple-step model for T-cell activation is proposed. In a series of in vitro studies, highly purified freshly isolated human peripheral blood T lymphocytes were stimulated through the CD28 receptor, with mAb or with natural ligands B7-1 or B7-2, along with TCR stimulation, in the absence of other costimulatory interactions. Ligation of the CD28 receptor, along with stimulation of the TCR, was found to up-regulate pleiotropic in vitro activities, including the secretion of both Th1 and Th2-type cytokines, B-cell help, and the development of cytotoxic activity. This costimulatory action involves CD4+ and CD8+ as well as naive and memory T-cell subsets. The expression of B7-1 and B7-2 on professional APC in situ in both normal and pathological tissues, and its up-regulation on monocytes by GM-CSF and IFN-gamma is consistent with this role. Additional studies have addressed the contribution of interactions between CD28 and B7-1 and B7-2 in T-cell activation initiated by normal un-engineered APC, such as stimulation with recall antigens and primary MLR. Blockade of the interaction between CD28 and B7-1/B7-2 under these conditions failed to completely inhibit T-cell responses or to induce anergy. Complete inhibition and anergy were, however, induced with a combination of CsA, targeting downstream TCR-triggered signalling, as well as anti-B7-1- and anti-B7-2-directed reagents. Interestingly, and in contrast to anti-LFA-1 mAb, the addition of anti-B7-1 or anti-B7-2 reagents could be delayed until at least 48 h after the initiation of T-cell stimulation, indicating a requirement for a late interaction between CD28 and its counter-receptors. Interactions between CD40L on activated T cells and CD40 on APC may serve to sustain, enhance or prolong the presentation of B7-1 or B7-2 on the APC, and thus to prevent anergy induction, or ineffective or abortive T-cell stimulation. Based on these data a sequential multiple-step T-cell activation model is proposed, and novel strategies for immuno-intervention can be designed.

Anaplastic large cell lymphoma: a clinicopathologic study of 53 patients

Fifty-three consecutive cases of adult CD30+ anaplastic large cell lymphoma (ALCL) have been analyzed. Thirty-six were classified as Hodgkin's disease like variety (HL) (67%) and seventeen as so-called common type (CT) (33%). All cases strongly expressed the CD30/Ki-1 antigen; the neoplastic cells expressed CD15, CD45 and EMA in 60%, 44% and 33% of cases, respectively; T. B and null phenotypes were found in 37%, 17% and 46% of cases. Bulky mediastinal, B symptoms, and extranodal disease at diagnosis were present in 36%, 49% and 25% of cases. EBV encoded latent membrane protein (LMP-1) was found in 10 cases. Of the 13 tested cases only 4 expressed a weak positivity of the CD40 molecule, in a fraction of the tumor cells; in the same cases CD21 was never found. Patients were treated with various protocols; of the 50 evaluable patients, 39 (78%) obtained a complete remission (CR), 3 (6%) a partial remission (PR) and 8 (16%) did not respond. The projected overall disease free survival (DFS) at 36 months is 70%. Only patients with advanced disease stage (III-IV) showed a statistically decreased DFS and survival. Only symptomatic and extranodal disease significantly appeared to influence survival. This study confirms the good outcome of this group of lymphomas and differs from other reports for some clinical (lower percentage of advanced stage, extranodal disease and skin infiltration) and pathological (HL/CT ratio and immunophenotype) features.

Single-cell analysis of T-cell receptor-gamma rearrangements in large-cell anaplastic lymphoma

Large-cell anaplastic lymphomas (LCAL) are characterized by their distinctive morphology together with expression of the CD30 antigen. In addition, a chromosomal translocation, t(2;5) (p23; q35), can be detected in most cases. A significant proportion of LCALs carry rearrangements of the T-cell receptor-gamma (TCR-gamma) locus and display a T-cell phenotype. In about a third of the cases, another type of non-Hodgkin-lymphoma precedes LCAL. Early transformations of non-Hodgkin's lymphoma into LCAL might escape clinical detection in a significant number of cases. The existence of clonally related lymphoid cells within the lymph node infiltrates must be claimed in these cases. Recently, a small-cell-predominant variant of LCAL was described in which only few large tumor cells expressing the CD30 antigen are found together with numerous small lymphocytes, which are frequently CD30-. This observation in particular prompted us to investigate the clonal relationship of the tumor cell compartment and admixed small lymphocytes in one case of common LCAL with T-cell genotype. For this purpose, we chose to amplify rearranged TCR-gamma sequences from single cells isolated from immunostained frozen sections by using a micromanipulator. A total of 119 cells were investigated. Amplification products were obtained in 17 of 79 CD3+ cells, 12 of 30 CD30+ cells, and three of 10 CD20+ cells. The nucleotide sequences were determined in 28 cells by nonradioactive sequencing. In 11 CD30+ cells, the predominant rearrangement of TCR-gamma was identified. No clonal diversity was observed. The small CD3+ lymphocytes were unrelated to the anaplastic CD30+ tumor cells. This report describes a method to analyze rearrangements of the TCR-gamma in single cells isolated from immunostained frozen sections. Application of this technique revealed an absence of clonal diversity in a case of LCAL and documented the polyclonal nature of admixed small CD3+ lymphocytes.

A pathologic study of Hodgkin's disease in Korea and its association with Epstein-Barr virus infection

BACKGROUND

The incidence of Hodgkin's disease (HD) in Korea and other Asian countries is much lower than in western countries and its association with the Epstein-Barr virus has not been well characterized.

METHODS

We evaluated the clinical, morphologic, and immunohistochemical features of 87 patients with Hodgkin's disease and also analyzed patients for Epstein-Barr virus (EBV) using in situ hybridization for EBV DNA, RNA, and latent membrane protein (LMP1).

RESULTS

There were 68 males and 19 females, with a mean age of 38 years. Mixed cellularity was the most prevalent subtype. Expression of EBV RNA (EBER:EBV-encoded RNA) was detected in 60 of 87 cases (69%): 1 of 1 (100%) with lymphocyte predominance, nodular; 4 of 7 (57%) with lymphocyte predominance, diffuse; 10 of 17 (59%) with nodular sclerosis; 38 of 51 (75%) with mixed cellularity; and 7 of 11 (64%) with lymphocyte depletion. Positivity was higher in advanced clinical stages; 4 of 7 patients (57%) with Stage I; 6 of 12 patients (50%) with Stage II: 7 of 9 patients (75%) with Stage III; and 5 of 5 patients (100%) with Stage IV HD EBV DNA was detected in 9 of 25 cases tested (36%). LMP1 was seen in 39 of 87 cases (45%). EBER and LMP1 positivity were higher in children and older adults than in adults aged between 15-50 years. Immediate early mRNAs (BHLF:Bam H-fragment, lower strand frame) was seen in a single patient.

CONCLUSIONS

HD in Korea showed a high incidence of mixed cellularity subtype and a high prevalence of EBV. EBV was detected in all subtypes, including a case of nodular lymphocytic predominance, and in all age groups, and showed correlation with mixed cellularity subtype and higher clinical stage. The expression of EBER and LMP were more frequently seen in children and older adults, suggesting a lowered immune surveillance in those age groups or a different pathophysiology of HD among different age groups.

Phenotype of Hodgkin and Sternberg-Reed cells and expression of CD57 (LEU7) antigen

Possible associations between the immunophenotype of Hodgkin (H) and Sternberg-Reed (S-R) cells, the expression of CD57 (Leu 7) antigen, and the presence of Epstein-Barr virus (EBV) were investigated in lymph node specimens from 50 cases of Hodgkin's disease (HD), including 26 cases of mixed cellularity and 24 cases of nodular sclerosis. Tissues were fixed in 10% neutral formalin, or/and B5 solution. H and S-R cells were CD30+, CD15+ (85% of the cases) and LCA (CD45). A proportion of neoplastic cells positive for either T-cell markers (CD3) or B-cell markers (CD20) was observed in 10% and 34% of the cases, respectively. Membrane positivity for CD57 antigen was found in H and S-R cells in 10 cases (8 cases of mixed cellularity, and 2 cases of nodular sclerosis). Such immunopositivity was only observed in B5-fixed sections. No staining for CD57 antigen was identified in H and S-R cells of any case with CD20 positive neoplastic cells. H and S-R cells of both CD57-positive and CD57-negative cases were further studied by immunohistochemistry for LMP1, by in-situ hybridization for EBER and by polymerase chain reaction (PCR) for EBV-DNA. No association was identified between the expression of CD57 antigen and the presence of EBV sequences, transcripts or proteins. Our findings do not support a B-cell origin for H and S-R cells in CD57-positive cases of Hodgkin's disease and suggest that these neoplastic cells may be related to natural killer (NK) or T-cells expressing CD57 antigen.

Ki-1 (CD30) anaplastic large-cell lymphoma in children

BACKGROUND

Ki-1 (CD30) ALCL is a rare and distinct type of high-grade NHL. A relevant feature is young age at presentation. Most reported pediatric series are retrospective analyses of heterogeneously-treated cases.

PATIENTS AND METHODS

Between 1976 and 1993, Ki-1 ALCL was diagnosed in 32 children (20 males 12 females; median age 9 years; 10.4% of childhood NHL). Before 1987, original diagnoses had been malignant histiocytosis in 14 cases, and immunoblastic NHL in 2. The treatment program for childhood T-lymphoblastic NHL, except for CNS prophylaxis, was applied in 28/32 cases. Radiotherapy to involved sites not in complete remission within 4 weeks after treatment start was used only prior to 1987.

RESULTS

In 78% of cases, Ki-1 ALCL presented in skin, bone, spleen and lung. Lymph nodes were frequently involved, often in association with periadenitis. Bone marrow and spinal fluid were negative in all cases. Eleven patients were classified as stage I/II, 21 as stage III. Fewer was present in 65% of patients. Cell phenotype was T in 21/32, and null in the remaining 11. Treatment results were evaluable in 27/32 children, all of whom achieved complete remission. Seven relapsed and 4 died of their disease. Five-year survival and progression-free survival were 84% and 72% respectively. Involvement of peripheral lymph nodes, absence of spleen, liver, lung and mediastinum involvement, and male sex were favourable indicators.

CONCLUSIONS

Ki-1 ALCL is a high-grade NHL with a relatively good prognosis when treated with multiagent intensive chemotherapy. Because of its clinical peculiarities a unique treatment approach in probably warranted.

Expression of c-myc and c-ras oncogenes in the neoplastic and non-neoplastic cells of Hodgkin's disease

The oncogenes c-myc and c-ras are known to elicit a cooperative tumorigenicity. In this study we investigated their role in the pathogenesis of Hodgkin's disease. The expression of these oncogenes was determined in Hodgkin's disease patients by avidin-biotin peroxidase complex immunohistochemical staining and was compared to their expression in patients with non-Hodgkin's lymphomas and inflammatory reactive lymph nodes. Of 29 examined patients with different histological types of Hodgkin's disease, 21 (72.4%) showed an elevated expression of c-myc and 28 (96.5%) of c-ras. Although this expression was marked especially in the neoplastic Reed-Sternberg cells, it was also noted in the numerous reactive cells present in the involved lymph nodes. By contrast, a much lower frequency of increased expression of these oncogenes was recorded in 19 patients with different grades of non-Hodgkin's lymphoma and in 29 patients with inflammatory reactive lymph nodes. The elevated expression of c-myc and c-ras in the neoplastic Reed-Sternberg cells may reflect an oncogenic event that directly activates these genes. However, their increased expression in the surrounding non-neoplastic cells probably results from signal transduction induced by certain growth-promoting factors possibly released by the Reed-Sternberg cells and that act paracrinally to stimulate the proliferation of the neighboring cells. Furthermore, the continuous c-ras elevation may impair the normal cell cycle control and thereby promote mutagenesis and overt malignancy.

Anaplastic large cell lymphoma: update of findings

The problem of anaplastic large cell lymphoma (ALCL) is extensively reviewed by depicting the clinical, pathological and biological characteristics of the four main varieties of ALCL: common, Hodgkin's like/Hodgkin-related, lympho-histiocytic, and giant-cell rich. Special emphasis is given to the differential diagnosis between ALCL Hodgkin like and Hodgkin's disease in the light of possible therapeutical differences.

Hodgkin's disease, follicular non-Hodgkin's lymphoma and a high grade B cell non-Hodgkin's lymphoma in the same patient

We report an unusual patient with a 21 year history of lymphoma of three different histological varieties: a low grade follicular non-Hodgkin's lymphoma, mixed cellularity Hodgkin's disease and a high grade B cell monocytoid non-Hodgkin's lymphoma.

Primary Hodgkin's disease of the lung

Three cases of Hodgkin's disease presenting primarily in the lung are described. All 3 patients presented with respiratory symptoms and chest X-rays revealed discrete masses within the lung parenchyma. CT examination of the mediastinum did not reveal regional or generalized lymphadenopathy at the time of diagnosis in 2 of the cases. A diagnosis of Hodgkin's disease was made on open lung biopsies and despite aggressive chemotherapy, 2 patients died within 2 yrs. The histological and immunocytochemical features of these cases were typical of that expected in Hodgkin's disease. However, the stated indolent course of primary pulmonary Hodgkin's disease is not invariable. Those patients with bilateral interstitial disease and systemic symptoms have a poor prognosis. Furthermore, it is difficult to exclude definitely lymph node involvement (although not enlarged) at the time of diagnosis. Since several cases described in the literature have concurrent and/or subsequent nodal involvement, the entity of primary pulmonary Hodgkin's disease without lymph node involvement is exceedingly rare.

Comparison of Epstein-Barr virus markers in Reed-Sternberg cells in adult Hodgkin's disease tissues from an industrialized and a developing country

The link between Hodgkin's disease (HD) and Epstein-Barr virus (EBV) is well documented in childhood and here the same hypothesis has been examined in adults, by comparing cases from an industrialized and a developing country. In this study the prevalence of EBV markers in nodal lesions of adult HD were compared in 21 patients from France (Fr) and 25 from Algeria (Al), all clinically staged during 1990-1992. Median age was 29 years. Histologic subtypes included lymphocytic predominance (LP) Fr 1; nodular sclerosis (NS) Fr 16, Al 16; mixed cellularity (MC) Fr 4, Al 9. EBV markers examined included expression of latent membrane protein (LMP) in Reed-Sternberg and Hodgkin cells (RSC) by immunochemistry; EBV-DNA and -RNA in situ hybridization (ISH); EBV-DNA by polymerase chain reaction (PCR). Results showed that RSC were LMP-positive in 4 (2 NS, 2 MC) French and 7 (3 NS, 4 MC) Algerian. All LMP+ cases were also positive for EBV DNA-RNA ISH. ISH was positive in RSC of 33% of the French and 72% of Algerian patients (p < 0.02). The positivity was more frequent in MC (77%) than in other histologic types (45%). The EBV genome was detected by PCR on DNA extracted from frozen samples in 84% of Fr and 95% of Al patients (100% of MC and 86% of other histologic types). Conclusion. The discrepancy between PCR and ISH results may be due to the lesser sensitivity of the ISH technique, or, alternatively, to the presence of EBV in the lymphoid cells surrounding RSC.(ABSTRACT TRUNCATED AT 250 WORDS)

Is Hodgkin's disease a unique entity?

The theoretical bases of Hodgkin's disease (HD) have recently been revised in the light of new findings obtained by means of immunohistochemistry and molecular analysis. These findings have questioned the concept that HD is a unique entity and have made the borders between HD and non-Hodgkin's lymphomas unclear. The clinical relevance of nodular lymphocyte predominance HD (LP-HD), the distinction between T-cell rich B-cell lymphoma and diffuse LP-HD, and the relationships between HD and anaplastic large cell lymphoma are reviewed and discussed.

Hodgkin's disease

BACKGROUND

Over three time periods, 1973-1977, 1978-1982, and 1983-1987, the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute collected all cases of Hodgkin's disease in designated geographic regions representative of the United States as a whole.

METHODS

The authors reviewed the data pertaining to 9418 microscopically confirmed cases of Hodgkin's disease and focused on trends that emerged over the time intervals of this study.

RESULTS

Hodgkin's disease had a bimodal distribution of age-specific incidence rates with two peaks in the age groups of 15-34 years and older than 55 years. Since 1973, the incidence of Hodgkin's disease in the younger age group increased progressively as a result of a marked increase in the incidence of the nodular sclerosis subtype. From the period 1973-1977 to 1983-1987, the age-adjusted incidence rate of nodular sclerosis rose from 1.1 to 1.6 per 100,000. In 1983-1987, nodular sclerosis represented 57.7% of Hodgkin's disease and occurred most often in whites, with an equal sex ratio. In females, this increase in incidence over time was most dramatic in young adult women. The overall incidence of the mixed cellularity subtype, 23.4% of Hodgkin's disease, remained stable although the age-specific incidence rate increased progressively in black males older than age 40 years. The incidence of the lymphocytic predominance subtype, 6.0% of Hodgkin's disease, remained stable over time, with a slight increase in adults older than age 50 years. The lymphocytic depletion subtype, 3.8% of Hodgkin's disease, occurred predominantly in the elderly; its incidence decreased, most likely the result of changes in diagnostic criteria, with many cases being reclassified as non-Hodgkin's lymphoma (NHL). Similarly, unclassifiable cases of Hodgkin's disease designated as miscellaneous, 9.1% of Hodgkin's disease, decreased over time, probably the result of improved classification. Nevertheless, a subset of cases of Hodgkin's disease remained difficult to subclassify. The human immunodeficiency virus (HIV) epidemic appears to be associated with an increased incidence of Hodgkin's disease in San Francisco County in adult males age 30-49 years, a population known to have a high prevalence of HIV infection.

CONCLUSION

The SEER data suggest that Hodgkin's disease is a heterogeneous entity composed of at least two different diseases--nodular sclerosis and mixed cellularity. Over the time course of this study, the incidence of nodular sclerosis increased dramatically, particularly in adolescents and young adults, whereas mixed cellularity remained stable. The incidence of Hodgkin's disease in the elderly decreased, most likely the result of our improved ability to diagnose both Hodgkin's disease and NHL and the realization that many cases of NHL had been misclassified as Hodgkin's disease. This decrease in Hodgkin's disease occurred predominantly in the lymphocytic depletion and miscellaneous groups.