Hepatosplenic T-cell lymphoma: an unusual case of a gamma delta T-cell lymphoma with a blast-like terminal transformation

A Retrospective Study of Multi-agent Chemotherapy including either Cyclophosphamide or Lomustine as Initial Therapy for Canine High-grade T-cell Lymphoma (2011-2017)

Multi-agent chemotherapy (vincristine, epirubicin and prednisolone) including either cyclophosphamide (CEOP) or lomustine (LEOP) was given as first-line chemotherapy to treatment-naïve canine lymphoma patients with measurable, high grade T-cell lymphoma (HGTCL). All patients responded to either CEOP or LEOP. Toxicity was typical of multi-agent chemotherapy protocols and 25% of dogs receiving lomustine exhibited mild-to-moderate ALT elevation and 29% grade 3 or 4 neutropenia. Median progression-free survival (100 versus 269 days) and overall survival (155 versus 327 days) were significantly higher in patients receiving LEOP compared to CEOP. Overall survival was improved for patients receiving LEOP compared to those receiving CEOP followed by lomustine-based rescue therapy. The results of this retrospective study support further evaluation of lomustine as part of first-line, multi-agent therapy for patients with HGTCL.

An Unusual Case of Hepatosplenic αβ T-Cell Lymphoma Presenting with Coombs'-Negative Hemolytic Anemia

Hepatosplenic T-cell lymphoma (HSTCL) is a rare and aggressive extranodal T-cell lymphoma that comprises <5% of peripheral T-cell lymphomas. The majority of cases harbor the γδ T-cell receptor (TCR), but recently, a few cases have been shown to express the αβ TCR. Comparison of these two subtypes (αβ and γδ) shows similar clinicopathologic and cytogenetic features; however, due to the paucity of reported cases, it is not clear whether they are prognostically distinct entities. We report a case of αβ HSTCL with a rather unusual presentation of Coombs’-negative hemolytic anemia. Diagnosis proved challenging due to an unusual blastoid morphology with the absence of typical intrasinusoidal distribution of tumor cells in the bone marrow. This unique case adds to the growing list of this rare subtype of T-cell lymphomas, which warrant urgent attention due to the lack of effective treatment options and dismal prognosis.

Gamma-delta t-cell lymphomas

Gamma-delta T-cell lymphomas are aggressive and rare diseases originating from gamma-delta lymphocytes. These cells, which naturally play a role in the innate, non-specific immune response, develop from thymic precursor in the bone marrow, lack the major histocompatibility complex restrictions and can be divided into two subpopulations: Vdelta1, mostly represented in the intestine, and Vdelta2, prevalently located in the skin, tonsils and lymph nodes. Chronic immunosuppression such as in solid organ transplanted subjects and prolonged antigenic exposure are probably the strongest risk factors for the triggering of lymphomagenesis. Two entities are recognised by the 2008 WHO Classification: hepatosplenic gamma-delta T-cell lymphoma (HSGDTL) and primary cutaneous gamma-delta T-cell lymphoma (PCGDTL). The former is more common among young males, presenting with B symptoms, splenomegaly and thrombocytopenia, usually with the absence of nodal involvement. Natural behaviour of HSGDTL is characterised by low response rates, poor treatment tolerability, common early progression of disease and disappointing survival figures. PCGDTL accounts for <1% of all primary cutaneous lymphomas, occurring in adults with relevant comorbidities. Cutaneous lesions may vary, but its clinical behaviour is usually aggressive and long-term survival is anecdotal. Available literature on gamma-delta T-cell lymphomas is fractioned, mostly consisting of case reports or small cumulative series. Therefore, clinical suspicion and diagnosis are usually delayed, and therapeutic management remains to be established. This review critically analyses available evidence on diagnosis, staging and behaviour of gamma-delta T-cell lymphomas, provides recommendations for therapeutic management in routine practice and discusses relevant unmet clinical needs for future studies.

Hepatosplenic γδ T-cell lymphoma: an overview

Peripheral T-cell lymphomas are a heterogeneous group of lymphoid malignancies. Among these, hepatosplenic γδ T-cell lymphoma (HTCL) represents an aggressive and treatment-resistant subgroup for which new avenues of treatment are critically needed. HTCL is characterized by primary extranodal distribution of the malignant cells with typical intrasinusoidal infiltration of the liver, spleen, and bone marrow, which results in hepatosplenomegaly and peripheral blood cytopenias. Another characteristic feature is the expression of γδ T-cell receptors. HTCL exhibits a rapid progressive course and an extremely poor response to currently known therapeutic strategies, with a 5-year overall survival rate of only 7%. In this review, we discuss the clinical, pathologic, and molecular characteristics of this disease, along with the challenges that are associated with its diagnosis and treatment.

Hepatosplenic gamma-delta T-cell lymphoma

Hepatosplenic T-cell lymphoma (HSTL) is a rare and aggressive extranodal lymphoma derived mostly from cytotoxic γδ T-cells. The peak incidence is in adolescents and young adults, and is more common in males. Up to 20% of HSTL arise in the setting of chronic immune suppression, most commonly solid organ transplantation or prolonged antigenic stimulation. Patients present with systemic symptoms (fever), abdominal pain, weakness, and marked hepatosplenomegaly in the absence of lymphadenopathy. Patients usually manifest marked thrombocytopenia, often with anaemia and leucopenia, a leukemic phase, and bone marrow involvement in 80% of cases. Lactate dehydrogenase levels are usually markedly elevated. HSTL exhibits a marked chemoresistance to currently used regimens, a rapidly progressive behavior, and dismal prognosis. Patients with post-transplant HSTL exhibit an especially poor outcome. Standard treatment has yet to be established. Anthracycline-based chemotherapy is associated with a satisfactory response in two thirds of patients, but poor long-term results. Complete remission is extremely uncommon, and most patients die from lymphoma within two years of diagnosis. A prognostic correlation between outcome and degree of thrombocytopenia has been reported. Relapsing disease is usually chemorefractory and fast growing, and patients' performance status and clinical conditions are poor. These aspects, as well as the lack of drugs with proven activity against HSTL, render salvage treatment almost impossible. A few cases of HSTL successfully treated with autologous or allogeneic stem-cell transplantation have been reported. The use of 2'-deoxycoformycin and other targeted therapies, such as alemtuzumab, anti-γδ TCR monoclonal antibodies, and anti-CD44 therapy, have shown promising results in anecdotal reports.

Natural killer cell lymphoma shares strikingly similar molecular features with a group of non-hepatosplenic γδ T-cell lymphoma and is highly sensitive to a novel aurora kinase A inhibitor in vitro

Natural killer (NK) cell lymphomas/leukemias are rare neoplasms with an aggressive clinical behavior. The majority of the cases belong to extranodal NK/T-cell lymphoma, nasal type (ENKTL) in the current WHO classification scheme. Gene-expression profiling (GEP) of 21 ENKTL and NK-cell lymphoma/leukemia patients, 17 NK- and T-cell lines and 5 indolent NK-cell large-granular-lymphocytic proliferation was performed and compared with 125 peripheral T-cell lymphoma (PTCL) patients previously studied. The molecular classifier derived for ENKTL patients was comprised of 84 transcripts with the majority of them contributed by the neoplastic NK cells. The classifier also identified a set of γδ-PTCLs both in the ENKTL cases as well as in cases initially classified as PTCL-not otherwise specified. These γδ-PTCLs expressed transcripts associated with the T-cell receptor (TCR)/CD3 complex, suggesting T cell rather than NK-cell lineage. They were very similar to NK-cell tumors by GEP, but were distinct from cytotoxic (αβ)-PTCL and hepatosplenic T-cell lymphoma, indicating derivation from an ontogenically and functionally distinct subset of γδ T cells. They showed distinct expression of Vγ9, Vδ2 transcripts and were positive for TCRγ, but negative for TCRβ by immunohistochemistry. Targeted inhibition of two oncogenic pathways (AURKA and NOTCH-1) by small-molecular inhibitors induced significant growth arrest in NK-cell lines, thus providing a rationale for clinical trials of these inhibitors in NK-cell malignancies.

Hepatosplenic T-cell lymphoma and inflammatory bowel disease

OBJECTIVE

This article reviews the current literature and knowledge about hepatosplenic T-cell lymphoma (HSTCL), providing an overview of the clinical features, a description of its pathology and immunophenotypic traits in relation to other lymphomas. In addition, we explore the history of reported cases of hepatosplenic T-cell lymphoma in relation to the possible existence of a causal relationship between infliximab use and HSTCL. The treatments for HSTCL will be briefly addressed.

METHODS

A comprehensive literature search using multiple databases was performed. Keyword search phrases including "lymphoma," "hepatosplenic T-cell lymphoma," "Inflammatory bowel disease," "6-mercaptopurine," and "infliximab" were used in various combinations. In addition references from published papers were reviewed as well.

RESULTS

There are over 200 reported cases of HSTCL. Only 22 cases of hepatosplenic T-cell lymphoma are associated with IBD treatment. Clinicians usually reserve immunomodulators and biologics for moderate to severe IBD cases. The ultimate goal of therapy is to control inflammation and therefore allow mucosal healing. IBD patients demonstrating mucosal healing are less likely to undergo surgery and experience complications related to their disease. We manipulate the immune system with corticosteroids, immunomodulators, and biologics, therefore causing bone marrow suppression. With bone marrow suppression, malignant degeneration may begin through selective uncontrolled cell proliferation, initiating HSTCL development in the genetically susceptible.

CONCLUSION

Hepatosplenic T-cell lymphoma is a rare disease, often with a poor outcome. With the increasing number of reported cases of HSTCL linked to the use of infliximab, adalimumab, and AZA/6-MP, there appears to be an undeniable association of HSTCL development with the use of these agents. This risk is unquantifiable. When considering the rarity of cases and the multiple complications with uncontrolled disease, however, the benefit of treatment far outweighs the risk.

Gamma-delta T-cell lymphomas

Peripheral T-cell lymphomas (TCLs) are uncommon neoplasms, accounting for about 12% of all lymphoid tumors worldwide. TCLs in which gammadelta T-cell receptors are expressed (gammadelta TCLs) are extremely aggressive and rare (<1% of lymphoid neoplasms). gammadelta TCLs originate from gammadelta T cells, a small subset of peripheral T cells with direct antigen recognition capability acting at the interface between innate and adaptive immunity. Two distinct gammadelta TCL entities are recognized: hepatosplenic T-cell lymphoma (HSTL) and primary cutaneous gammadelta T-cell lymphoma (PCGD-TCL). HSTL is a well-characterized extranodal lymphoma that has a disguised onset, secondary to intrasinusoidal infiltration of the spleen, liver and bone marrow, has a rapidly progressive course that is poorly responsive to chemotherapy, and often ensues in the setting of immune system suppression. PCGD-TCL can present with prominent epidermal involvement or with a panniculitis-like clinical picture that can be complicated by a concurrent hemophagocytic syndrome; the disease shows biological and phenotypic overlap with other extranodal gammadelta TCLs that involve the respiratory or gastrointestinal tract mucosa. The regular application of phenotypic and molecular techniques is crucial for the diagnosis of gammadelta TCLs. In this Review, we discuss the clinical and biological features, the diagnostic challenges and the therapeutic perspectives of HSTL and PCGD-TCL.

Hepatosplenic lymphoma in a dog

We describe a case of a dog with hepatosplenic lymphoma, a disease characterized by infiltration of the liver, spleen, and bone marrow with gammadelta T cells, absence of peripheral lymphadenopathy, and an aggressive clinical course. Physical examination findings, hematologic and biochemical abnormalities, and clinical course of the disease in this patient were similar to those in humans. Immunophenotyping of liver and spleen aspirates supported an antemortem diagnosis of T-cell lymphoma consistent with hepatosplenic lymphoma. The diagnosis was confirmed postmortem by a combination of routine histopathology, showing a consistent pattern of organ involvement, and immunohistochemistry showing the infiltrating neoplastic lymphocytes to be T cells expressing the gammadelta T-cell receptor. To our knowledge, this is the first reported case of hepatosplenic lymphoma in a dog.

Gammadelta T-cell lymphomas

T-cell lymphomas expressing the gammadelta T-cell receptor (TCR) are uncommon, although their frequency may be underestimated. They show a broad clinicopathological spectrum. Besides precursor T-cell lymphoblastic leukemia/lymphoma, various post-thymic gammadelta T-cell neoplasms have been recognized. Among these, hepatosplenic gammadelta T-cell lymphoma constitutes the prototype of T-cell lymphomas expressing the gammadelta TCR and was listed as a provisional entity in the Revised European-American Lymphoma (REAL) classification. The recognition of this lymphoma subtype was further supported by the demonstration that the neoplasm results from a proliferation of nonactivated cytotoxic T cells and is associated with a recurrent cytogenetic abnormality, the isochromosome 7q. More recently, a few cases of hepatosplenic T-cell lymphoma with similar clinicopathologic features and alphabeta phenotype have been described that are thought to belong to the same entity, and the term "hepatosplenic T-cell lymphoma" is preferred in the current World Health Organization (WHO) classification. Most nonhepatosplenic gammadelta T-cell lymphomas occur in skin or in mucosal sites, a location that parallels that of normal gammadelta T cells. In contrast to hepatosplenic gammadelta T-cell lymphomas, they show an important clinical and morphological heterogeneity, have an activated cytotoxic phenotype, and are not believed to constitute a single disease entity.

Preferential expansion of Vgamma9-JgammaP/Vdelta2-Jdelta3 gammadelta T cells in nasal T-cell lymphoma and chronic active Epstein-Barr virus infection

We recently established an Epstein-Barr virus (EBV)-positive gammadelta T-cell line from a nasal T/natural killer (NK)-cell lymphoma (Nagata H, Konno A, Kimura N, Zhang Y, Kimura M, Demachi A, Sekine T, Yamamoto K, Shimizu N: Characterization of novel natural killer (NK)-cell and gammadelta T-cell lines established from primary lesions of nasal T/NK-cell lymphomas associated with the Epstein-Barr virus. Blood 2001, 97:708-713). Subsequently, we established two novel EBV-positive gammadelta T-cell lines from the peripheral blood of patients with chronic active EBV infection. Analysis of the terminal repeat of EBV showed that the three cell lines consisted of monoclonal populations, and flow cytometry showed that they had a common phenotype of gammadelta T cells: CD3(+) CD4(-) CD8(-) CD16(-) CD19(-) CD56(+) CD57(-) HLA-DR(+) T-cell receptor (TCR) alphabeta(-) TCR gammadelta(+). Analysis for the expression of TCR by flow cytometry showed that all three cell lines were Vgamma9(+)/Vdelta2(+), but negative for VgammaI, Vdelta1, or Vdelta3 TCR. Southern blot analysis for TCR genes showed that the three cell lines had a common rearrangement of Vgamma9-JgammaP and Jdelta3 genes. Polymerase chain reaction and sequence analysis of the junction between Vdelta and Jdelta genes revealed that the Jdelta3 genes were rearranged with the Vdelta2 genes. In contrast, none of the EBV-negative gammadelta T-cell lines, Molt-14, Peer, or Loucy, which were analyzed for controls, had Vgamma9 or Vdelta2 TCR, or a rearrangement of Jdelta3 genes. These results indicated that Vgamma9-JgammaP/Vdelta2-Jdelta3(+) gammadelta T cells were preferentially affected by EBV and expanded in patients with nasal gammadelta T-cell lymphoma and chronic active EBV infection. Jdelta3(+) gammadelta T cells are known to be a very minor population in gammadelta T cells of peripheral blood, whereas Vgamma9-JgammaP/Vdelta2-Jdelta1(+) cells are the major population. The close association of EBV with this particular gammadelta T-cell population may provide a key to the etiology of EBV-positive lymphoproliferative diseases.

Lymphoproliferative disease of granular lymphocytes with T-cell receptor gamma delta-positive phenotype: restricted usage of T-cell receptor gamma and delta subunit genes

Lymphoproliferative disease of granular lymphocytes (LDGL) is characterized by more than 0.5 x 109/L of proliferating granular lymphocytes in the peripheral blood. Because of its rarity, the characteristics of LDGL with T-cell receptor (TCR) gammadelta phenotype (gammadeltaT-LDGL) have not yet been identified. This report describes the clinical, hematological, and immunological findings of four patients with this disease. In two cases, the clinical course was indolent and the other two patients required various therapies. The cells had a common immunophenotype: CD3+, CD4-, CD16+, CD56-, CD57-, CD122-, TCR-gammadelta+, and three were CD8-positive. The immunopurified TCR-gammadelta cells from the patients expressed only Vgamma9 and Vdelta1. Spectratyping and sequencing showed mono- or oligoclonality for TCRgamma and TCRdelta subunit genes. Soluble Fas ligand in sera was significantly elevated in all patients. These findings suggest that gammadeltaT-LDGL qualifies as a distinct disease entity.

Fluorescence in situ hybridization study of chromosome 7 aberrations in hepatosplenic T-cell lymphoma: isochromosome 7q as a common abnormality accumulating in forms with features of cytologic progression

Hepatosplenic gamma delta T-cell lymphoma (HS gamma delta TCL) is a rare and aggressive subtype of peripheral T-cell lymphoma that has been associated cytogenetically with the isochromosome 7q [i(7)(q10)]. The incidence of this aberration and its relevance to pathogenesis of HS gamma delta TCL is still unknown. We investigated the status of chromosome 7 in 12 HSTCL cases, including nine with a typical gamma delta phenotype, one with a so-called T-cell receptor (TCR)-silent phenotype, and two with the variant alpha beta phenotype. We analyzed available fresh and archival material using a dual-color interphase fluorescence in situ hybridization (FISH) approach with 7p and 7q probes. A significant population of cells with predominance of 7q signals was detected in 10 cases (eight gamma delta, one alpha beta, and one TCR silent), and two lymphomas did not show clonal 7p/7q signal imbalances. In four of 10 cases with chromosome 7 aberrations, a hybridization pattern indicative of the presence of one chromosome 7 and one i(7)(q10) was found. In four other cases, the configuration of signals (2 x 7p/3 x 7q) suggested the presence of the i(7)(q10) and additional structural aberrations involving the second chromosome 7. In two cases, including one alpha beta phenotypic variant, a variety of FISH patterns equivalent to two to five copies of i(7)(q10) or numerical and structural aberrations of second chromosome 7 has been detected. These findings support cytogenetic data pointing to a characteristic association of i(7)(q10) with HSTCL, irrespective of the immunophenotype of malignant cells. An increased number of 7q signals was found in three cases with cytologic features of progression, indicating a tendency of HSTCL to multiply the i(7)(q10) chromosome during evolution.

Hepatosplenic gammadelta-T-cell lymphoma with leukemic course after renal transplantation

Hepatosplenic gammadelta-T-cell lymphoma (HSTCL) is a rare extranodal T-cell non-Hodgkin's lymphoma (T-NHL) with only 46 well-documented cases in medical literature. Notably, a relatively high number of these case reports (15%) describe the occurrence of HSTCL after solid organ transplantation. We describe the case of a 45-year-old man who developed a leukemic HSTCL 5 years after renal transplantation and continous immunosuppression with cyclosporine A and prednisolone. After a rapid clinical course, the patient died and autopsy was performed. The malignant lymphocytes showed a natural killer-like gammadelta-T-cell phenotype (CD2(+), CD3(+), CD7(+), TCR gammadelta(+), CD56(+), TIA-1(+), CD4(-), CD8(-), and TCR alphabeta(-)) and infiltrated the sinusoids of liver and the red pulp of the spleen. Cytogenetically, an isochromosome 7q, trisomy 8, Y-loss, and a translocation t(1;4) was detectable. This case shows the difficulties of recognizing HSTCL early in the clinical course and underlines that all types of T-NHL, nodal as well as extranodal, have to be considered in the differential diagnosis of posttransplantation lymphoproliferative disorders. Moreover, HSTCL seems to occur as a specific late complication of solid organ transplantation.

Hepatosplenic gamma/delta T-cell lymphoma in bone marrow. A sinusoidal neoplasm with blastic cytologic features

We report 8 cases of hepatosplenic T-cell lymphoma (HSTCL) involving bone marrow and correlate histologic findings with disease progression. Immunophenotypic analysis demonstrated mature, aberrant gamma/delta T-cell immunophenotypes. Isochromosome 7q was identified in 4 cases; 1 case showed the t(7;14)(q34;q13). Seven of 7 cases tested had monoclonal TCR gamma gene rearrangements. The initial diagnostic bone marrow biopsy specimens were hypercellular with a frequently subtle, predominantly sinusoidal infiltrate of atypical small to medium-sized lymphoid cells. In all cases, aspirate smears at diagnosis and in subsequent specimens contained malignant cells that resembled blasts, some with fine cytoplasmic granules. With progression, the pattern of HSTCL in bone marrow biopsy specimens became increasingly interstitial, and the neoplastic cells became larger. In aspirate smears, the proportion of blasts increased. Seven patients died; 1 was lost to follow-up. Autopsy performed on 1 patient demonstrated malignant cells within vascular channels in all organs sampled, with relatively little tumor formation, resembling intravascular lymphoma at these sites. HSTCL often can be recognized in bone marrow by its unique combination of a sinusoidal pattern in core biopsy specimens and blastic cytology in aspirate smears.

Hepatosplenic gamma/delta T-cell lymphoma in immunocompromised patients. Report of two cases and review of literature

We describe 2 male patients in whom hepatosplenic gamma/delta T-cell lymphoma (HSTL) developed 6 and 10 years after renal transplantation. The onset was abrupt with systemic symptoms, cytopenia, and hepatosplenomegaly. The histologic examination of the spleen (case 1), liver, and bone marrow revealed sinusoidal infiltrates of markedly abnormal lymphocytes. The neoplastic cells in these cases were CD2+, CD3+, CD4-, CD5-, CD7+, CD8+, CD16+, CD56+, beta F1-negative, and TIA-1-negative. Both cases displayed clonal rearrangement of the T-cell receptor (TCR) delta gene and the TCR beta gene. The spleen in case 1 was positive for Epstein-Barr virus genome and showed TCR-gamma gene rearrangement by polymerase chain reaction. Isochromosome 7 [i(7)(q10)] was found in each case. Both patients died within 4 months of diagnosis. HSTL has been reported in only 5 renal transplant recipients. HSTL may be relatively more frequent in immunocompromised patients compared with the general population.

Hepatosplenic alphabeta T-cell lymphomas: a report of 14 cases and comparison with hepatosplenic gammadelta T-cell lymphomas

Hepatosplenic gammadelta T-cell lymphoma is a distinct entity, characterized by occurrence in young adult males with hepatosplenomegaly, B-symptoms, peripheral blood cytopenias, and no lymphadenopathy; lymphomatous infiltrates in the splenic red pulp, hepatic sinusoids, and bone marrow sinuses; T-cell receptor (TCR) gammadelta chains and a cytotoxic T-cell phenotype; isochromosome 7q; and an aggressive clinical course. In comparison, this study describes the clinicopathologic features of 14 hepatosplenic T-cell lymphomas expressing TCR alphabeta chains. They occurred in 11 women and 3 men with a median age of 36 years. Clinical presentation was similar to that described previously for hepatosplenic gammadelta T-cell lymphomas, except for the female preponderance and age distribution (5 patients younger than 13 years of age and 5 patients older than 50 years of age). Disease distribution was primarily in the splenic red pulp and hepatic sinusoids, although liver infiltrates were largely periportal in four cases. Bone marrow involvement, observed in eight patients, was usually interstitial and/or within the sinuses. Lymph nodes were involved in five patients, although lymphadenopathy was demonstrable in only two. Ten cases were composed of intermediate-size tumor cells with round/oval nuclei, slightly dispersed chromatin, inconspicuous nucleoli, and scant to moderate amounts of cytoplasm. Four lymphomas contained primarily large cells with irregular nuclei, dispersed chromatin, discernible nucleoli, and moderate to abundant cytoplasm. Tumor cells in all 14 lymphomas were cytotoxic alphabeta T-cells; 13 co-expressed natural killer cell-associated antigens and showed T-cell clonality. Three lymphomas were associated with Epstein-Barr virus. Two of four cases had an isochromosome 7q. Eleven patients are dead, eight within a year of diagnosis, and two patients have maintained complete remissions after combination chemotherapy. These data show that hepatosplenic T-cell lymphomas include an alphabeta-subtype. This group, along with the previously recognized gammadelta group, should be recognized as phenotypically heterogeneous subtypes of the same disease entity.

Characterization of novel natural killer (NK)-cell and gammadelta T-cell lines established from primary lesions of nasal T/NK-cell lymphomas associated with the Epstein-Barr virus

Studies on nasal T/natural killer (NK)-cell lymphoma have been hampered by its tendency to cause necrosis. Thus, the establishment of cell lines of this neoplasm would seem to be valuable. This study attempted to establish cell lines from primary lesions of this tumor, and successfully obtained 2 novel Epstein-Barr virus (EBV)-positive cell lines, SNK-6 and SNT-8, by means of high-dose recombinant interleukin 2. Flow cytometry showed that SNK-6 had an NK-cell phenotype, CD3- CD4- CD8- CD19- CD56+ T-cell receptor (TCR) alpha/beta- TCR gamma/delta-, whereas SNT-8 was CD3+ CD4- CD8- CD19- CD56+ TCR alpha/beta- TCR gamma/delta+. These were consistent with immunophenotypes of their original tumors, and the cell lines had monoclonal EBV clones identical to ones in their original tumors. Thus, the cell lines developed from cells forming the primary lesions. Genotypic analysis showed that SNK-6 had unrearranged TCR and immunoglobulin heavy-chain genes, supporting the conclusion that SNK-6 was of NK-cell lineage. On the other hand, SNT-8 had rearranged TCR beta-, gamma-, and delta-chain genes, and together with its phenotype, SNT-8 proved to be a gammadelta T-cell line. This is the first report of the establishment of cell lines from primary lesions of nasal T/NK cell lymphomas, and the results demonstrated that there are at least 2 lineages, NK- and gammadelta T-cell, in this neoplasm. Moreover, it has been suggested that nasal T/NK cell lymphomas of these lineages may belong to the same clinicopathologic entity because both types of cases shared common clinical and histopathologic features.

In vitro and in vivo effects of 2'-deoxycoformycin (Pentostatin) on tumour cells from human gammadelta+ T-cell malignancies

Hepatosplenic gammadelta+ T-cell lymphoma represents a rare neoplasm of post-thymic phenotype, characterized by an aggressive clinical course and a poor response to conventional chemotherapy. In the present study, we have examined the cytotoxic effects of the purine analogue 2'-deoxycoformycin (dCF) on cultured mononuclear cells and purified gammadelta+ tumour cells from bone marrow or peripheral blood of four patients with hepatosplenic gammadelta+ T-cell lymphoma. At a concentration of 10 microM, dCF, in the presence of 2'-deoxyadenosine (dAdo), displayed an early and selective cytotoxic effect on gammadelta+ tumour T cells. After 48 h of in vitro exposure to dCF, the absolute number of viable CD3+/gammadelta+ tumour T cells was reduced by more than 90% in all samples with respect to control cultures, with absolute counts of viable CD3+/alphabeta+ lymphocytes being reduced only by 6-40% of the initial cell input. Analysis of cultures after 5 d of exposure to dCF plus dAdo revealed the persistence of normal CD3+/alphabeta+ T cells, which accounted, however, for only 20-25% of the initial cell input. Accordingly, the combination of dCF (10-100 microM) plus dAdo was able to induce a dose-dependent inhibition of clonogenic growth and [3H]-thymidine incorporation in purified CD3+/CD4-/CD8- gammadelta+ tumour cells. We also report that one patient with hepatosplenic gammadelta+ T-cell lymphoma in terminal leukaemic phase showed a striking haematological response to single-agent dCF given as fourth-line treatment. In particular, the selective clearance of gammadelta+ tumour T cells in peripheral blood and bone marrow was observed starting after the second course of treatment. Our results suggest that dCF may represent a potentially active drug for the management of this aggressive form of T-cell lymphoma.

Hepatosplenic T cell lymphoma. A review on 45 cases since the first report describing the disease as a distinct lymphoma entity in 1990

Peripheral T cell lymphomas are a heterogeneous group of post-thymic, mature lymphoid malignancies, accounting for approximately 10-15% of all non-Hodgkin's lymphomas. A rare entity within this group is represented by hepatosplenic gammadelta T cell lymphoma, which is characterized by primary extranodal disease with typical sinusoidal or sinusal infiltration of the liver and the spleen, respectively, by expression of the T cell receptor gammadelta chain, and by a number of other frequent clinicopathological features including aggressive course of disease. In contrast to these common attributes some biologic characteristics such as expression of cytotoxic proteins and cytotoxic activity have been controversial. In this review, clinicopathological, immunophenotypical, molecular biological, cytogenetical and biological findings, and diagnostic and therapeutic difficulties in hepatosplenic gammadelta T cell lymphoma are discussed.

gammadelta T-cell lymphomas: a homogeneous entity?

gammadelta T-cells comprise an immunologically distinct lymphoid population, characterized by specific morphological, phenotypical and functional properties. Therefore it seems reasonable to speculate that neoplasms derived from this particular T-cell subset display distinct features. Indeed, the prototype gammadelta T-cell lymphoma, hepatosplenic T-cell lymphoma constitutes a unique clinicopathological entitity which is intimately associated with a gammadelta T-cell phenotype. However, gammadelta T-cell lymphomas have also been described in other extranodal sites where, unlike reactive gammadelta T-cells and hepatosplenic gammadelta T-cell lymphomas, they display an important morphological heterogeneity. Moreover, these nonhepatosplenic gammadelta T-cell lymphomas are essentially not that different from their alphabeta T-cell receptor for antigen (TCR)-expressing counterparts and thus may be incorporated in the established T-cell lymphoma subclasses. However, subtle differences regarding their histopathological appearance as well as their biological behaviour indicate that further studies to determine the exact significance of TCR expression are required. Such inquiries may contribute to the general understanding of T-cell lymphomagenesis in general, which is still obscure.

Consistency of isochromosome 7q and trisomy 8 in hepatosplenic gammadelta T-cell lymphoma: detection by fluorescence In situ hybridization of a splenic touch-preparation from a pediatric patient

Hepatosplenic gamma-delta (gammadelta) T-cell lymphoma is a rare but increasingly recognized lymphoid malignancy predominantly affecting young adult males. It is not well appreciated in the pediatric population. We report the third case of this aggressive lymphoma in a child as well as additional support for the consistency of the recently discovered cytogenetic abnormalities, isochromosome 7q and trisomy 8, which in this case were documented using fluorescence in situ hybridization (FISH) of a touch-preparation of the spleen.

Post transplant CD8+ gammadelta T-cell lymphoma associated with human herpes virus-6 infection

Gammadelta T-cell lymphoma is a rare T-cell lymphoproliferative disorder that has been reported in both immunocompetent and immunocompromised persons. This report describes a forty eight year old patient who developed gammadelta T-cell lymphoma four years after undergoing living-related kidney transplantation. The lymphoma expressed CD2, CD3, CD7, CD8 and CD56, and the gammadelta T-cell receptor and did not express CD5, CD4 and the alphabeta T-cell receptor. In addition, HHV-6 was cultured from the patient's bone marrow, marking the first time that this virus has been associated with gammadelta T-cell lymphoma. Since all patients with gammadelta T-cell lymphoma described to date have responded poorly to standard combination chemotherapies, the patient was treated with the purine analogue 2-chlorodeoxyadenosine. While he responded transiently to treatment, long term remission was not achieved indicating that additional therapeutic approches still need to be developed, for the management of this disorder.

Hepato-splenic gammadelta T-cell lymphoma: a rare entity mimicking the hemophagocytic syndrome

Hepatosplenic gammadelta T-cell lymphoma is a rare histologic type of the peripheral T-cell lymphomas, clinically characterized by predominant involvement of liver and spleen, no or little adenopathy, and an often aggressive course; it affects mainly adolescents and young adults, with a male predominance. Postthymic T-cell malignancies are heterogeneous in their clinical and laboratory features. Among the gammadelta postthymic T-cell lymphomas, two distinct entities (cutaneous and hepatosplenic, respectively) are reported in the literature. The former shows predominant multiple involvement of the skin and subcutaneous tissue; it occurs mostly in older patients and the phenotype is CD3-, CD4-, CD8-. Because of the small number of reports, the course of the disease was unknown. The latter shows a clinical picture characterized by hepatosplenomegaly, no or little adenopathy, and sometimes systemic symptoms (fever, cytopenias likely due to hypersplenism); it presents a peculiar sinusoidal involvement of liver and spleen. The bone marrow histologic feature often reveals a little infiltration, especially sinusoidal and easily underestimated phenotype: CD2+, CD3+, CD7+, CD5-, CD4-, CD8-, CD44+. Few cases of this lymphoma associated by hemophagocytic syndrome are described (Sun, 1990; Kadin, 1981; Jaffe, 1983). We report a case of a young man with a rapid and fatal course in which the more important clinical feature was hemophagocytosis. The diagnosis of lymphoma was very difficult because of paucity of histologic involvement, and only the rearrangement of TCR gamma chain gene by polymerase chain reaction on paraffin sections confirmed a clonal T-cell proliferation.

Molecular evidence of bone marrow involvement in advanced case ot Tgammadelta lymphoma with secondary myelofibrosis

We describe the case of a middle-aged man with long indolent course of generalized Tgammadelta lymphoma. The onset of secondary myelofibrosis made cytological monitoring of the bone marrow infiltrates impossible. As during progression of the disease splenectomy revealed typical histological features of a high-grade hepatosplenic Tgammadelta lymphoma, the low-grade bone infiltrate was considered a secondary lymphoma. The use of the polymerase chain reaction helped to detect a constant and identical monoclonal rearrangement pattern of the T-cell receptor gamma-chain gene in both bone marrow and splenic T-cell infiltrates. The notion of a secondary spread of malignant T-cells to the bone marrow was thereby confirmed despite striking cytological differences between bone marrow and splenic infiltrates. This is the first report of a diagnostic DNA-based molecular approach using fixed decalcified bone marrow. This method may provide a major tool when dealing with myelofibrosis, which normally hampers sampling of cytological specimens.

T gamma/delta hepatosplenic lymphoma in a heart transplant patient after an Epstein-Barr virus positive lymphoproliferative disorder: a case report

BACKGROUND

An unusual case of a peripheral T-cell lymphoma of T gamma/delta hepatosplenic type (Tgamma/deltaHSL) that arose in a child 5 years after she received a heart transplant and 9 months after she developed Epstein-Barr virus (EBV) positive, B-cell lymphoid hyperplasia involving the tonsils is presented. The majority of the reported cases of Tgamma/deltaHSL have been described in young adult men without antecedent immunodeficiency; several well documented cases of Tgamma/deltaHSL in the posttransplant setting have been described previously, but none has been described in a child (or an adult) with a previously diagnosed EBV+ B-cell lymphoid hyperplasia.

METHODS

Standard histologic, immunohistochemical, flow cytometric, and molecular genetic techniques were used in the evaluation of diagnostic material.

RESULTS

The patient's Tgamma/deltaHSL involved the spleen in a predominantly cordal pattern, and infiltrated the liver in an exclusively sinusoidal distribution. Bone marrow involvement was focal and interstitial. In all locations, malignant cells were of intermediate or large size and had oval nuclei with coarse chromatin, with a scant or moderate amount of eosinophilic cytoplasm. This Tgamma/deltaHSL expressed the characteristic CD2+, CD3+, [CD4- CD8-], Tdelta1+ phenotype, and malignant cells also expressed the natural killer cell marker CD56. Cytogenetic studies demonstrated isochromosome 7q with the addition of trisomy 8 as the tumor progressed. Southern blot analysis demonstrated clonal rearrangements of the gamma, delta, and beta loci of the T-cell receptor but did not identify EBV DNA within the tumor cells.

CONCLUSIONS

This case highlights the fact that a full range of lymphoid proliferations is possible in the posttransplantation period, and that a prior diagnosis of a B-cell disorder does not preclude the development of a subsequent T-cell posttransplant lymphoproliferative disorder (PTLD), which should be formally evaluated, especially if clinical circumstances appear atypical for a PTLD of the "usual" (EBV-related, B-cell) type.

A Southwest Oncology Group perspective on the Revised European-American Lymphoma classification

In recent years several new morphologic entities and a new classification system, Revised European-American Lymphoma Classification (REAL), have been proposed which affect the nomenclature and classification of lymphoid malignancies. This article reviews some of the features of the more common new entities, places these entities in immunologic context, explores the clinical utility of these entities, and provides a working clinical organization to the names.

Hepatosplenic gamma/delta T-cell lymphoma: a report of two cases in immunocompromised patients, associated with isochromosome 7q

Two cases of peripheral T-cell lymphoma, characterized by hepatosplenic presentation and gamma/delta T-cell receptor phenotype on malignant cells, are reported. Little is known about the chromosomal changes in these peculiar lymphomas. We report the cytogenetic analysis of these two patients. Isochromosome 7q and trisomy 8 were observed. These abnormalities were reported previously in five cases of gamma/delta T-cell lymphoma. These two patients had lymphomatous infiltration of the spleen, liver, bone marrow, and (in one case) lymph nodes. These abnormalities occurred in immunocompromised patients (i.e., immunosuppressive therapy for kidney transplantation and chemotherapy for Hodgkin's disease), without Epstein-Barr virus infection stigmata in tumor cells.

Hepatosplenic gammadelta T-cell lymphoma: ultrastructural, immunophenotypic, and functional evidence for cytotoxic T lymphocyte differentiation

Hepatosplenic gammadelta T cell lymphoma (TCL) is a rare, aggressive subset of peripheral TCL that presents with hepatosplenomegaly and cytopenias. Detailed clinicopathological, ultrastructural, and cytogenetic analyses of these lymphomas are limited; functional characteristics of these lymphomas are unknown. We have undertaken a clinicopathological, immunophenotypic, ultrastructural, cytogenetic, and functional analysis of three hepatosplenic gammadelta TCLs. All patients presented with massive hepatosplenomegaly and anemia, thrombocytopenia, or severe neutropenia; terminal blastlike transformation occurred in one patient. Combination chemotherapy had no response in two patients, but induced complete remission in one. gammadelta T cell receptor (TCR) expression and clonal TCRdelta gene rearrangements were documented in each case. Two different subsets of gammadelta TCL were identified based on delta chain variable region usage; two lymphomas were Vdelta1+, whereas the third was negative for both Vdelta1 and Vdelta2. Cytogenetic analysis was performed on two lymphomas; isochromosome 7q and probable trisomy 8 was shown in one of the Vdelta1+ lymphomas, whereas the Vdelta1 negative lymphoma had 14p+ with t(1;14)(q21;p13). NK cell-associated antigens (CD11c, CD16, or CD56) and cytotoxic T lymphocyte (CTL) effector proteins (perforin, granzyme B, TIA-1, and Fas ligand) were expressed by each lymphoma; dense core cytolytic granules were observed by electron microscopy in both lymphomas studied. Functional studies performed in two cases showed TCR-mediated cytolysis of P815 x 2 FcR+ cells induced by anti-CD3 in a redirected cytolysis assay in one of the CD56+, Vdelta1+ lymphomas, whereas IFNgamma secretion was induced by anti-CD3 in the CD56-, Vdelta1 negative lymphoma. These studies show that hepatosplenic gammadelta TCLs have CTL differentiation, retain functional activity in vitro, and are derived from at least two gammadelta T cell subsets.

A nodal gamma/delta T-cell lymphoma with an association of Epstein-Barr virus

The postthymic gamma/delta T-cell lymphoma is rare, and most occur as extranodal tumors, e.g., in hepatosplenic or cutaneous forms. We here report an unusual nodal case that initially presented as a T-zone lymphoma. The neoplasm recurred as systemic lymphadenopathy 25 months after complete remission with terminal high-grade transformation. Phenotypic analysis showed CD1-, CD2+, CD3+, CD4-, CD5-, CD7+, CD8+, CD10-, CD16-, CD19-, CD20-, CD21-, CD25-, CD56-, CD57-, T-cell receptor (TCR) alpha/beta antigens negative, TCR gamma/delta antigens positive, and an HLA-DR+ phenotype. Cytogenetic studies showed clonal chromosomal translocations involving chromosomes 1, 5, 6, 8, 15, and X in eight of 15 cells; t(X;5;1)(q13;q13;p22) and t(6;15;8)(p22;q26;q13). Genotypic analysis showed the same clone, characterized by the TCR gamma-chain gene rearrangement pattern, to be present in both initial and recurrent tumors. The lymphoma cells were also demonstrated to express the latent membrane protein-1 by immunohistochemistry and EBV-encoded small RNAs by in situ hybridization. Southern blot analysis using the probe of the terminal repeat demonstrated incorporation of multiple copies of EBV in the recurrent tumor. However, the initial lesion, which contained a smaller number of EBV-positive cells, showed no such evidence of clonal proliferation. These data suggest that EBV may be associated with high-grade transformation, although its exact role in lymphomagenesis remains uncertain. The present study also adds to our understanding of the clinicopathologic spectrum of gamma/delta T-cell neoplasia.

Peripheral CD4+ CD8- gammadelta T cell lymphoma: a case report with multiparameter analyses

A 72-year-old Japanese man presented with CD4+ T cell receptor (TCR) gammadelta T cell lymphoma involving bilateral cervical lymph nodes. No involvement by tumor was observed in the liver, spleen, nasal cavity, or bone marrow throughout his clinical course. Although the tumor adequately responded to chemotherapy and irradiation, he relapsed with short remission and a slowly aggressive clinical course, and died 24 months after onset. Simultaneous expression of TCR gammadelta with other T-cell antigens on the lymphoma cells was analyzed by 3-color flow cytometry (3-FCM), and showed a unique phenotype CD3+ CD4+ CD8- CD7- CD5+ CD2++ TCR alphabeta (WT31)- betaF1-TCR gammadelta1 (11F2)+ TCR delta1+. Cytogenetic analysis showed 79-81 and structural abnormalities consisting of del(1)(p11) and i(17)(q10). But no abnormality was identified in chromosome 7. DNA analysis revealed gene rearrangements of TCRgamma and delta, while a nongerm line band in TCRbeta was aberrantly seen. These observations suggest a new subtype of gammadelta T-cell lymphoma, which is characterized by CD4 positivity and by a clinical course not as aggressive as other predominant subtypes.

Nasal T-cell lymphoma causally associated with Epstein-Barr virus: clinicopathologic, phenotypic, and genotypic studies

BACKGROUND

The authors have previously demonstrated nasal T-cell lymphoma (NTL) associated with Epstein-Barr virus (EBV). The detailed clinical, phenotypic, and genotypic features and the role of EBV in lymphomagenesis remain to be clarified.

METHODS

The study group consisted of 18 patients with NTL. The phenotype was determined by immunoperoxidase staining with various monoclonal antibodies. Genotypic study was done using Southern blot hybridization. The presence of EBV-encoded small nuclear early region (EBER) RNA and EBV DNA were determined by in situ hybridization. The expression of EBV-encoded nuclear antigen (EBNA) and latent membrane protein (LMP1) were identified by immunohistologic methods. Clonotypic analysis of EBV genomes was performed by Southern blot hybridization with EBV termini fragment probe.

RESULTS

The clinical features of NTL were characterized as prolonged fever (16 patients), widespread dissemination into distant sites (13 patients), and poor prognosis with a median survival of only 6 months. EBER transcripts were identified in 16 of 18 patients. Monoclonal EBV genomes EBNA1 and LMP1 were also detected in all EBER-positive cases tested. All 18 patients expressed pan-T antigens such as MT1, CD45RO, and/or CD2. The rearrangements of T-cell receptor (TCR)-beta, -gamma, and/or -delta genes were shown in all 11 patients tested. The natural killer (NK) cell phenotype CD56 was expressed in all EBV-positive cases tested, and was not detected in EBV-negative cases. Seven EBV-positive cases expressed a TCR-delta chain with rearranged TCR-gamma or -delta genes whereas both EBV-negative cases corresponded to alpha beta T-cell lymphoma, which expressed a TCR-beta chain with a rearranged TCR-beta gene.

CONCLUSIONS

These data suggest that EBV-positive NTL may be derived from the lineage of NK-like T-cells or gamma delta T-cells, and that EBV may play a role in lymphomagenesis. Therefore, we propose that NTL which has peculiar clinical and histologic features could be classified as a new lymphoma entity.

Aggressive primary hepatic lymphoma in Chinese patients. Presentation, pathologic features, and outcome

BACKGROUND

Primary non-Hodgkin's lymphoma of the liver is rare. In this study, the presentation, pathologic features, and outcome of seven Chinese patients with primary hepatic lymphoma are described.

METHODS

From 1984 to 1994, the clinical records of 14 Chinese patients with non-Hodgkin's lymphoma and histologically proven liver involvement were reviewed. Seven (four males, three females; median age, 54 years) were considered to have primary hepatic lymphoma. Histologic and immunohistochemical studies were performed on paraffin embedded liver tissue.

RESULTS

"B" symptoms including fever (86%) and weight loss (57%) were the most striking presenting features. Hepatomegaly was present in all patients, splenomegaly in three (43%), and thrombocytopenia in six (86%). Only one patient was hepatitis B surface antigen-seropositive. None had preexisting liver disease. Histologic subtypes, though heterogeneous, were mostly unfavorable and consisted of diffuse large cell lymphoma (two patients), small lymphocytic lymphoma (one patient), lymphoblastic lymphoma (one case), mantle cell lymphoma (one patient), anaplastic large cell Ki-1 lymphoma (one patient), and hepatosplenic T-cell lymphoma (one patient). Three patients expressed B-cell and 2 expressed T-cell phenotypes. Six patients received cytotoxic chemotherapy. One had resection and one had splenectomy, but none achieved complete remission, and only one remained alive as of this writing. The median survival was 3.7 months (range, 8 days to 47.7 months).

CONCLUSION

Chinese patients with primary non-Hodgkin's lymphoma of the liver have prominent "B" symptoms, disease with a highly aggressive course, a poor response to local and systemic treatment, and short survival. Hepatitis B virus infection is not a major etiologic factor for these patients.

Hepatosplenic gamma-delta T-cell malignant lymphoma: report of the first case in childhood, including molecular minimal residual disease follow-up

We report the first case of T-cell gamma delta+ hepatosplenic malignant lymphoma in childhood. Tumour-specific oligoprobes were developed against the single V1-J1 rearrangement of the delta T-cell receptor (TCR) gene in order to perform minimal residual disease (MRD) studies. Molecular analysis in serial bone marrow samples proved to be of predictive value concerning the clinical outcome. Clonotypic DNA was not detected in peripheral blood during the course of the disease until a refractory terminal leukaemic phase took place 18 months after the diagnosis. This case demonstrates the usefulness of MRD studies to monitor the course of disease in at least some subsets of peripheral T-cell lymphomas.