Immunologic abnormalities in angioimmunoblastic lymphadenopathy

Novel tumour-infiltrating lymphocyte-related risk stratification based by flow cytometry for patients with de novo angioimmunoblastic T cell lymphoma

Tumour-infiltrating lymphocytes (TILs) account for a large proportion of tumour microenvironment (TME) in angioimmunoblastic T cell lymphoma (AITL), and at present the significance of TIL in TME of AITL remains unclear. Overall, 50 de novo AITL patients undergoing lymph node flow cytometry from 2014 to 2019 were retrospectively analysed to assess the relationship between TILs and AITL prognosis. We found that high TIL-Bs (≥ 42.4%, p = 0.004) and high CD4:CD8 (≥ 0.85, p = 0.024) were independent favourable prognostic factors for de novo AITL in univariate or multivariate analyses. New TIL-related risk stratification was established based on TIL-Bs and CD4:CD8 factors. Patients in the low-risk group (TIL-Bs ≥ 42.4% and CD4:CD8 ≥ 0.85) had significantly better overall survival than the high-risk (TIL-Bs < 42.4% and CD4:CD8 < 0.85) (p < 0.001) or intermediate-risk group (TIL-Bs ≥ 42.4% and CD4:CD8 < 0.85 or TIL-Bs < 42.4% and CD4:CD8 ≥ 0.85) (p = 0.011). To our knowledge, our cohort is the largest one focusing on the TILs in de novo cases of AITL by analysing lymph node samples using flow cytometry, which is the first time to comprehensively consider humoral immunity and cellular immunity influence on AITL. Our new risk stratification was valuable and useful in evaluating prognosis of AITL and guiding immunotherapy strategies.

Pilot trial of ibrutinib in patients with relapsed or refractory T-cell lymphoma

Ibrutinib has previously been shown to inhibit Bruton's tyrosine kinase (BTK) and interleukin-2-inducible T-cell kinase (ITK), which mediate B-cell and T-cell receptor signaling, respectively. BTK inhibition with ibrutinib has demonstrated impressive clinical responses in a variety of B-cell malignancies. Whether ibrutinib inhibition of ITK can lead to clinical response in T-cell malignancies is unknown. We hypothesized that ibrutinib-mediated ITK inhibition in T-cell lymphoma would result in decreased signaling through the T-cell receptor pathway and promote antitumor immune response by driving selective cytotoxic Th1 CD4 effector T-cell differentiation. This pilot clinical trial evaluated 2 dose levels of ibrutinib: 560 and 840 mg orally daily. Fourteen patients with relapsed, refractory peripheral T-cell lymphoma and cutaneous T-cell lymphoma were enrolled. Both dose levels were safe and well tolerated, and no dose-limiting toxicities were observed. One patient achieved a partial response (overall response rate, 8% [1/13]). ITK occupancy studies demonstrated a mean occupancy of 50% (range, 15%-80%). Higher ITK occupancy of more than 50% correlated with higher serum levels of tumor necrosis factor-α and interferon-γ and favored a Th1 phenotype. Our data suggest that ibrutinib inhibition of ITK has limited clinical activity in T-cell lymphoma. This study is registered at www.clinicaltrials.gov as #NCT02309580.

T- and NK-Cell Lymphomas and Systemic Lymphoproliferative Disorders and the Immunodeficiency Setting: 2015 SH/EAHP Workshop Report-Part 4

OBJECTIVES

The 2015 Workshop of the Society for Hematopathology/European Association for Haematopathology aimed to review immunodeficiency-related T- and natural killer (NK)-cell lymphoproliferations.

METHODS

The Workshop Panel reviewed 88 T- or NK-cell lymphoproliferations and rendered consensus diagnoses.

RESULTS

Hyperplasias of T-cell subsets may be clonal; retained architecture and the clinical setting support a benign diagnosis. Specific associations include hepatosplenic T-cell lymphoma with iatrogenic immunosuppression and breast implants with an indolent variant of anaplastic large cell lymphoma. Epstein-Barr virus (EBV)-positive T-cell lymphomas rarely occur in the acquired immunodeficiency setting. Systemic T- and NK-cell lymphoma of childhood overlaps with chronic active EBV and reversible hemophagocytic lymphohistiocytosis-related T-cell lymphoproliferations.

CONCLUSIONS

Immunodeficiencies predispose to T-cell hyperplasias, which must not be overdiagnosed as lymphoma. Many T-cell lymphomas in the immunodeficiency setting are likely coincidental, with specific exceptions. Systemic T- or NK-cell lymphomas are part of a spectrum of EBV+ T or NK lymphoproliferations and can present in the acquired immunodeficiency setting.

The microenvironment in T-cell lymphomas: emerging themes

Peripheral T-cell lymphomas (PTCLs) are heterogeneous and uncommon malignancies characterized by an aggressive clinical course and a mostly poor outcome with current treatment strategies. Despite novel insights into their pathobiology provided by recent genome-wide molecular studies, several entities remain poorly characterized. In addition to the neoplastic cell population, PTCLs have a microenvironment component, composed of non-tumor cells and stroma, which is quantitatively and qualitatively variable, and which may have an effect on their pathological and clinical features. The best example is provided by angioimmunoblastic T-cell lymphoma (AITL), a designation reflecting the typical vascularization and reactive immunoblastic content of the tumor tissues. In this disease, a complex network of interactions between the lymphoma cells and the microenvironment exists, presumably mediated by the neoplastic T cells with follicular helper T-cell properties. A better understanding of the crosstalk between neoplastic T or NK cells and their microenvironment may have important implications for guiding the development of novel therapies.

Successful cidofovir therapy of progressive multifocal leukoencephalopathy preceding angioimmunoblastic T-cell lymphoma

Progressive multifocal leukoencephalopathy (PML) is a subacute demyelinating infectious disease, caused by the human polyomavirus JC (JCV), that usually occurs in immunocompromised patients. In this setting, PML has been observed in increasing numbers of patients with hematological malignancies, mostly lymphoproliferative B-cell disorders. Despite attempts with various drugs, PML has generally remained unresponsive to treatment. We report the successful use of cidofovir in a patient who developed PML 6 months before angioimmunoblastic T-cell lymphoma (AITL) was diagnosed. To the best of our knowledge, this is the first case of PML in AITL. Our case demonstrates the expanding clinical importance of PML in hematological conditions, and neurological symptoms and/or white matter changes on central nervous system imaging should arouse the suspicion of PML and lead to rapid cidofovir introduction. Progressive multifocal leukoencephalopathy (PML) is a subacute demyelinating infectious disease, caused by the human polyomavirus JC (JCV), that usually occurs in immunocompromised patients. In this setting, PML has been observed in increasing numbers of patients with hematological malignancies, mostly lymphoproliferative B-cell disorders. Despite attempts with various drugs, PML has generally remained unresponsive to treatment. We report the successful use of cidofovir in a patient who developed PML 6 months before angioimmunoblastic T-cell lymphoma (AITL) was diagnosed. To the best of our knowledge, this is the first case of PML in AITL. Our case demonstrates the expanding clinical importance of PML in hematological conditions, and neurological symptoms and/or white matter changes on central nervous system imaging should arouse the suspicion of PML and lead to rapid cidofovir introduction.

Angioimmunoblastic T cell lymphoma: Treatment experience with cyclosporine

Angioimmunoblastic T cell lymphoma is a distinct entity for which there is no standard therapy. On the basis of the rationale that CsA may represent a novel drug for AITL, a disease with considerable immune dysregulation, and encouraging case reports, the authors have treated 12 patients with this agent. Ten had failed prior steroids and/or chemotherapy and two had no prior therapy. CsA was administered at a dose of 3 - 5 mg/kg PO bid for 6 - 8 weeks and gradually tapered by 50 mg every 1 - 3 weeks. Responding patients received a maintenance dose of 50 - 100 mg, with a gradual taper after a maximal response was achieved as tolerated. Doses were titrated for renal dysfunction or hypertension. CsA levels were not monitored. Eight of 12 patients responded (three complete and five partial remissions). Dose reductions were required in six patients; renal insufficiency (n = 3), fatigue (n = 2), and hypertension (n = 1). Two patients developed acute infections and one patient died shortly after active treatment. These results suggest that CsA deserves further testing as a novel therapy for AITL. By interrupting T-cell activation, CsA may alter the immune dysregulation that characterizes AILT. The efficacy of CsA is being explored in patients with recurrent AILT in a prospective trial (ECOG 2402).

Pathobiology and molecular profiling of peripheral T-cell lymphomas

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of rare diseases, usually manifesting clinical aggressiveness. Although important novel insights into the pathobiology of nodal PTCL have been gained recently from molecular profiling studies and clinico-pathological analyses, the pathogenetic molecular lesions remain to be deciphered for most entities. Angioimmunoblastic T-cell lymphoma (AITL) comprises CD4+ CXCL13+ neoplastic cells displaying overlapping immunophenotypical and molecular features with normal follicular helper T cells. This derivation might account for the presence of a prominent non-neoplastic component in AITL tissues and the clinical manifestations of the disease reflective of an immunological dysfunction. ALK+ anaplastic large cell lymphoma (ALCL), defined by ALK gene translocation with various gene partners, is composed of CD30+ ALK+ cells with a cytotoxic phenotype and usually carries a good prognosis. ALK- ALCL, now considered as a distinct disease entity, is morphologically and immunophenotypically similar to ALK+ ALCL, except for ALK expression, but has distinctive molecular features. PTCL, not otherwise specified (PTCL, NOS), the largest PTCL category, which is derived from activated CD4+ (or CD8+) T cells, is markedly heterogeneous, including at the molecular level. Gene expression profiling approaches have identified novel biomarkers of potential therapeutic interest, and suggest the existence of molecularly distinct PTCL, NOS subgroups.

Pathobiology and Molecular Profiling of Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of rare diseases, usually manifesting clinical aggressiveness. Although important novel insights into the pathobiology of nodal PTCL have been gained recently from molecular profiling studies and clinico-pathological analyses, the pathogenetic molecular lesions remain to be deciphered for most entities. Angioimmunoblastic T-cell lymphoma (AITL) comprises CD4+ CXCL13+ neoplastic cells displaying overlapping immunophenotypical and molecular features with normal follicular helper T cells. This derivation might account for the presence of a prominent non-neoplastic component in AITL tissues and the clinical manifestations of the disease reflective of an immunological dysfunction. ALK+ anaplastic large cell lymphoma (ALCL), defined by ALK gene translocation with various gene partners, is composed of CD30+ ALK+ cells with a cytotoxic phenotype and usually carries a good prognosis. ALK– ALCL, now considered as a distinct disease entity, is morphologically and immunophenotypically similar to ALK+ ALCL, except for ALK expression, but has distinctive molecular features. PTCL, not otherwise specified (PTCL, NOS), the largest PTCL category, which is derived from activated CD4+ (or CD8+) T cells, is markedly heterogeneous, including at the molecular level. Gene expression profiling approaches have identified novel biomarkers of potential therapeutic interest, and suggest the existence of molecularly distinct PTCL, NOS subgroups.

Lymphomes T angio-immunoblastiques

Angioimmunoblastic T-cell lymphoma most often affects the elderly. Patients present with generalized lymphadenopathy and systemic symptoms; half also have hepatomegaly, splenomegaly and a rash. Polyclonal hypergammaglobulinemia, elevated lactate dehydrogenase, and anemia are the main laboratory abnormalities. Autoimmune phenomena (including autoimmune hemolytic anemia, immunologic thrombocytopenia, and autoantibodies) are common. Lymph node biopsy is needed to confirm this diagnosis. Genetic analysis that reveals a monoclonal T-cell population is also relevant. The underlying immune deficiency explains the frequency of infections. Most patients are treated with combination chemotherapy. Autologous stem cell transplantation is proposed to the youngest. Immunosuppressive drugs may be appropriate for elderly or relapsing patients. The overall 5-year survival rate is 30%.

Angioimmunoblastic T-cell lymphoma: clinical and laboratory features at diagnosis in 77 patients

We retrospectively analyzed 77 patients with pathologically diagnosed angioimmunoblastic T-cell lymphoma from a single city. There were 43 men and 34 women; the median age was 64.5 years (range, 30-91 yr). Average time between first symptoms of the disease and diagnosis was 3.6 months. At diagnosis, peripheral nodes were present in all but 1 patient, and were generalized in 90% of cases. Constitutional symptoms were reported in 77% of cases and spleen enlargement in 51%. A cutaneous eruption--morbilliform, urticarial, or more polymorphic--was present in 45% of patients; in one-third of them, the eruption occurred after drug administration. Other clinical manifestations included pleuritis (22%); arthralgia or arthritis (17%); ear, nose, and throat involvement (14%); central or peripheral neurologic manifestations (10%); and ascites (5%). Most patients presented with advanced disease at diagnosis (bone marrow involvement in 60% of cases). The main laboratory abnormalities were elevated lactate dehydrogenase levels (71%), inflammatory syndrome (67%), hypergammaglobulinemia (50%), anemia (51%), and lymphopenia (52%). Auto- or disimmune manifestations were reported in one-third of patients: autoimmune hemolytic anemia was present at diagnosis in 19% of patients and thrombocytopenic purpura in 7%. Documented vasculitis was described in 12% of cases. Clonality was analyzed in lymph nodes in 47 patients: T-cell and B-cell clones were found in 45 (96%) and 20 (45%) patients, respectively. Chromosomal abnormalities were identified in 62% of cases: trisomies 3, 5, 18, 19, additional X chromosome, and deletion of chromosome 7 were the most common abnormalities. The current study underlines the diversity of presenting manifestations of angioimmunoblastic T-cell lymphoma.

Angioimmunoblastic T cell lymphoma with an unusual proliferation of Epstein-Barr virus-associated large B cells arising in a patient with progressive systemic sclerosis

We report an unusual case of angioimmunoblastic T cell lymphoma arising in the setting of 5 years of immunosuppressive treatment for progressive systemic sclerosis. The lymph node lesion was accompanied by large blastic B cells with an association of Epstein-Barr virus. Southern blot study demonstrated the clonal rearrangement of T cell receptor beta-chain gene, but not of immunoglobulin heavy chain gene. Phenotypical examination of the lymph node also revealed the predominance of CD4+ T cells in addition to the proliferation of follicular dendritic cells, but no light chain restriction in large B cell components. In the clinical and laboratory aspects, neutrophilia (15.8 x 10(9)/l) and plasmacytosis (40%) in bone marrow were noted, which were considered to be closely related to elevated serum granulocyte colony-stimulating factor, interleukin (IL)-4 and IL-6. Based on the combined data described here, our preferred diagnosis was angioimmunoblastic T cell lymphoma with Epstein-Barr virus-associated B cell lymphoproliferative disorder, the pathogenesis of which was suggested to be closely associated with immunosuppressive treatment for progressive systemic sclerosis.

Epstein–Barr Virus Load Correlating with Clinical Manifestation and Treatment Response in a Patient with Angioimmunoblastic T-Cell Lymphoma

Epstein–Barr virus (EBV)-associated lymphoma may arise secondary to angioimmunoblastic T-cell lymphoma (AITL). The prognosis is poor despite chemotherapy and experimental therapies. We report on a 40-year-old woman with AITL without obvious immunodeficiency in which EBV-associated lymphoma developed. The occurrence and size of enlarged lymph nodes correlated strongly with the EBV load in serum (EBVL). Treatment with valacyclovir at the early stage resulted in a drastic more than 3 log10 decrease of EBVL and complete remission. However, valacyclovir had to be stopped after 6 months due to side effects, and the lymphoma reoccurred 3 months later associated with increasing EBVL. Eventually started cytotoxic chemo- and anti-CD20 therapy resulted only in partial remission. The lymphoma progressed and 33 months after it was diagnosed the patient died. This case report demonstrates the close association of EBVL and AITL and a beneficial effect of antiviral therapy at an initial stage of disease manifestation.

Epstein-Barr virus-associated B-cell lymphoproliferative disorders in angloimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma, unspecified

Various patterns of Epstein-Barr virus (EBV)-associated B-cell lymphoproliferation occur in patients with immunodeficiency. We studied 17 cases of T-cell lymphoma displaying extensive EBV-driven B-cell lymphoproliferation or simultaneous/subsequent EBV-associated B-cell lymphoma. In 10 cases of angioimmunoblastic T-cell lymphoma, an uncommonly prominent population of EBV+ atypical, activated, focally confluent large transformed B cells was found in the background of T-cell lymphoma. In 4 cases, an EBV-associated B-cell neoplasm (3 diffuse large B-cell lymphomas, 1 plasmacytoma) occurred in patients with T-cell lymphoma. Three cases were composite lymphomas of a peripheral T-cell lymphoma, unspecified, combined with EBV-associated diffuse large B-cell lymphoma. The transformed B-cell population displayed EBV latency types 2 and 3. Monoclonal and oligoclonal B-cell populations were detected in 5 and 6 cases, respectively. Similar to other states of immunodeficiency, disease-related and therapy-induced immunosuppression in T-cell lymphoma may lead to a prominent EBV-associated B-cell lymphoproliferation and to EBV+ B-cell neoplasms.

Survival and clonal expansion of mutating "forbidden" (immunoglobulin receptor-deficient) epstein-barr virus-infected b cells in angioimmunoblastic t cell lymphoma

Angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is a peculiar T cell lymphoma, as expanding B cell clones are often present besides the malignant T cell clones. In addition, large numbers of Epstein-Barr virus (EBV)-infected B cells are frequently observed. To analyze the differentiation status and clonal composition of EBV-harboring B cells in AILD, single EBV-infected cells were micromanipulated from lymph nodes of six patients with frequent EBV(+) cells and their rearranged immunoglobulin (Ig) genes analyzed. Most EBV-infected B cells carried mutated Ig genes, indicating that in AILD, EBV preferentially resides in memory and/or germinal center B cells. EBV(+) B cell clones observed in all six cases ranged from small polyclonal to large monoclonal expansions and often showed ongoing somatic hypermutation while EBV(-) B cells showed little tendency for clonal expansion. Surprisingly, many members of expanding B cell clones had acquired destructive mutations in originally functional V gene rearrangements and showed an unfavorable high load of replacement mutations in the framework regions, indicating that they accumulated mutations over repeated rounds of mutation and division while not being selected through their antigen receptor. This sustained selection-free accumulation of somatic mutations is unique to AILD. Moreover, the survival and clonal expansion of "forbidden" (i.e., Ig-deficient) B cells has not been observed before in vivo and thus represents a novel type of viral latency in the B cell compartment. It is likely the interplay between the microenvironment in AILD lymph nodes and the viral transformation that leads to the survival and clonal expansion of Ig-less B cells.

Angioimmunoblastic lymphadenopathy presenting as superior vena caval obstruction

A 60-year-old man presented with features of superior vena cava (SVC) obstruction. On evaluation, he was diagnosed as having angioimmunoblastic lymphadenopathy with dysproteinemia (AILD). SVC obstruction due to AILD, to our knowledge, has not been described.

Increased serum levels of soluble IL-2 receptor, CD30 and CD8 molecules, and gamma-interferon in angioimmunoblastic lymphadenopathy: possible pathogenetic role of immunoactivation mechanisms

Abnormal immunoreaction associated with increased cell activation phenomena might play a role in the pathogenetic events leading to the development of angioimmunoblastic lymphadenopathy (AILD). In the present study we investigated the serum levels of some soluble molecules related to cell activation in 24 patients with AILD at presentation. In particular, we measured by immunoenzymatic or immunoradiometric techniques the levels of the Tac peptide (sIL-2R), soluble CD30 (sCD30) and CD8 (sCD8) antigens, and gamma-IFN (gIFN). The results show that all the above molecules are increased as compared to normal controls, with a different pattern of increase for the different molecules. The sIL-2R levels were very high in all cases with no overlap between AILD and control samples (mean 6315 +/- 3374 U/ml, controls 271 +/- 112 U/ml, P less than 0.001). Very high values of the sCD30 antigen (722 +/- 895 U/ml) were detected in all cases but five, as opposed to the lack of detectable levels in controls. A significant increase of sCD8 (978 +/- 646 U/ml, controls 334 +/- 95 U/ml, P less than 0.01) and gIFN (329 +/- 236 U/ml, controls 97 +/- 43 U/ml, P less than 0.01) was also observed with some overlap between AILD samples and controls. The above findings further support the view that a condition of abnormally enhanced cell activation is likely to play a central role in the pathogenetic events leading to the composite clinicopathological picture of AILD.

Unusual Association of Hairy Cell Leukemia and Monoclonal Large Granular Lymphocyte Proliferation

The exceptional association of Hairy cell leukemia (HCL) and monoclonal large granular lymphocyte (LGL) proliferation is reported in the same patient. Immunophenotypic analysis, showed that most of the PBMC expressed CD3 and HNK-1 molecules, while in the bone marrow biopsy an infiltration by CD22 +/CD25 + lymphoid cells was detectable. The monoclonal rearrangement of βTTCR genes in the PBMC, suggests that the increased LGL is not reactive. Nevertheless, a possible interaction between the two entities is proposed. The high sIL-2R serum levels, related to proliferation of hairy cells, might account for the lack of NK activity observed in the LGL.

Danazol in treatment of angio-immunoblastic lymphadenopathy

The clinical manifestations of angio-immunoblastic lymphadenopathy (AILD) suggest that there is an abnormality in the immune system. Most patients with AILD die from opportunistic infections associated with lymphocyte depletion. As chemotherapy further increases the already high susceptibility of infections, the therapeutic management of AILD is difficult. The achievement of complete remission (CR) by the patient described here using a danazol-based regimen raises the hope that treatment of this disease with a noncytotoxic drug may be possible. The rationale behind and advantages of using danazol are discussed.