Hepatosplenic gamma-delta T-cell lymphoma

Data mining and safety analysis of traditional immunosuppressive drugs: a pharmacovigilance investigation based on the FAERS database

OBJECTIVE

The purpose of this study aimed to explore the new and serious adverse events(AEs) of Tacrolimus(FK506), cyclosporine(CsA), azathioprine(AZA), mycophenolate mofetil(MMF), cyclophosphamide(CTX) and methotrexate(MTX), which have not been concerned.

METHODS

The FAERS data from January 2016 and December 2022 were selected for disproportionality analysis to discover the potential risks of traditional immunosuppressive drugs.

RESULTS

Compared with CsA, FK506 has more frequent transplant rejection, and is more related to renal impairment, COVID-19, cytomegalovirus infection and aspergillus infection. However, CsA has a high infection-related fatality rate. In addition, we also found some serious and rare AE in other drugs which were rarely reported in previous studies. For example, AZA is closely related to hepatosplenic T-cell lymphoma with high fatality rate and MTX is strongly related to hypofibrinogenemia.

CONCLUSION

The AEs report on this study confirmed that the results were basically consistent with the previous studies, but there were also some important safety signals that were inconsistent with or not mentioned in previous published studies.

EXPERT OPINION

The opinion section discusses some of the limitations and shortcomings, proposing the areas where more effort should be invested in order to improve the safety of immunosuppressive drugs.

Prolonged fever with pancytopenia and massive hepatosplenomegaly

Prolonged fever with pancytopenia and hepatosplenomegaly is a clinical entity frequently encountered by physicians. The diagnosis of such cases is challenging due to the diversity of differential diagnoses. Hepatosplenic T-cell lymphoma is a rare and aggressive type of non-Hodgkin lymphoma that can present with massive hepatosplenomegaly, pancytopenia and prolonged fever. Most of the patients are young men and the majority are associated with chronic immunosuppression. We report a 40-year-old immunocompetent woman with prolonged fever and pancytopenia due to hepatosplenic T-cell lymphoma.

Successful treatment of hepatosplenic T-cell lymphoma with fludarabine, high-dose cytarabine and subsequent unrelated umbilical cord blood transplantation

Hepatosplenic T-cell lymphoma (HSTCL) is a rare subtype of peripheral T-cell lymphoma that occurs most often in adolescents and young adults and is rare in children. Because of the aggressive clinical course, resistance to conventional chemotherapy and poor prognosis of HSTCL, an effective treatment has not been established. We report the case of a 3-year-old girl with HSTCL presenting with trilineage myelodysplasia. Although the HSTCL was refractory to conventional chemotherapy, remission was achieved with salvage chemotherapy that included fludarabine and cytarabine, which were shown to be effective in the drug sensitivity assay. After undergoing umbilical cord blood transplantation with a conditioning regimen consisting of etoposide, cyclophosphamide and total body irradiation, the patient has remained in complete remission for 8 years. Single-nucleotide polymorphism array analysis revealed heterozygous deletions of PAX5 (9p), ETV6 (12p) and homozygous deletions of CDKN2A (9p). Exome analysis showed a heterozygous nonsense c.2961C>G (p.Tyr987Ter) variant of the KMT2C gene. To improve the poor prognosis of HSTCL, the chemotherapeutic regimen can be selected for each patient on the basis of drug sensitivity and molecular genetic characteristics.

Hepatosplenic T-cell lymphoma: a rare but challenging entity

Hepatosplenic T-cell lymphoma (HSTCL) is a rare T-cell neoplasm that most commonly arises from a small subset of γ/δ T-cell receptor-expressing lymphocytes. HSTCL is more common in adolescent and young adults and has a rapidly progressive clinical course and poor outcome due to its refractoriness to conventional chemotherapy regimens. Approximately 20% of the cases arise in the background of chronic immunosuppression or immune dysregulation. Patients commonly present with constitutional symptoms, hepatic and liver enlargement, and cytopenias; hematophagocytic syndrome can also occur. The most frequent chromosomal aberrations associated with HSTCL are isochromosome 7q and trisomy 8, and most cases harbor mutations in genes involved in chromatin modification or the JAK/STAT pathway. The rarity of this disease, along with lack of nodal involvement and presenting symptoms that mimic different entities including infectious etiologies, makes this lymphoma a significant diagnostic challenge. In this review, we highlight the clinical and pathologic features of HSTCL. Moreover, we summarize the results of recent molecular studies suggesting potential targets for novel therapeutics strategies.

Intensive Induction Therapy Compared With CHOP for Hepatosplenic T-cell Lymphoma

INTRODUCTION

Hepatosplenic T-cell lymphoma (HSTCL) is a rare peripheral T-cell lymphoma that disproportionately affects individuals with a clinical history of immunosuppression. It carries a poor prognosis, and, owing to its rarity, there is no single or well-established treatment.

PATIENTS AND METHODS

We conducted the largest-to-date individual-level meta-analysis based on literature searches to determine the best induction therapy for HSTCL. We compared response rates and survival among patients who received "non-CHOP-based" induction with regimens containing cytarabine, etoposide, and/or platinum-based treatment to those receiving treatment with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) or CHOP-like therapy. We also review additional regimens including alemtuzumab and pentostatin, and assessed the role of consolidation with hematopoietic stem-cell transplantation (HSCT).

RESULTS

We identified 166 patients with HSTCL, 118 of whom had sufficient information on induction treatment and survival. Eighty-four patients received non-CHOP-based (N = 34) or CHOP/CHOP-like (N = 50) induction treatment. Non-CHOP-based induction was associated with a complete/partial response rate of 82% compared with 52% (P = .006) with CHOP/CHOP-like and increased median overall survival (P = .00014). Our data showed that maximum survival among patients with HSTCL was achieved with non-CHOP-based induction followed by consolidation with HSCT.

CONCLUSIONS

Non-CHOP-based induction appears superior to CHOP/CHOP-like induction in both achieving complete/partial response and durable survival. Induction therapy of HSTCL should be intensified with non-CHOP-based regimens and followed by consolidation with HSCT in eligible patients.

Human Peripheral Blood Gamma Delta T Cells: Report on a Series of Healthy Caucasian Portuguese Adults and Comprehensive Review of the Literature

Gamma delta T cells (Tc) are divided according to the type of Vδ and Vγ chains they express, with two major γδ Tc subsets being recognized in humans: Vδ2Vγ9 and Vδ1. Despite many studies in pathological conditions, only a few have quantified the γδ Tc subsets in healthy adults, and a comprehensive review of the factors influencing its representation in the blood is missing. Here we quantified the total γδ Tc and the Vδ2/Vγ9 and Vδ1 Tc subsets in the blood from 30 healthy, Caucasian, Portuguese adults, we characterized their immunophenotype by 8-color flow cytometry, focusing in a few relevant Tc markers (CD3/TCR-γδ, CD5, CD8), and costimulatory (CD28), cytotoxic (CD16) and adhesion (CD56) molecules, and we examined the impacts of age and gender. Additionally, we reviewed the literature on the influences of race/ethnicity, age, gender, special periods of life, past infections, diet, medications and concomitant diseases on γδ Tc and their subsets. Given the multitude of factors influencing the γδ Tc repertoire and immunophenotype and the high variation observed, caution should be taken in interpreting “abnormal” γδ Tc values and repertoire deviations, and the clinical significance of small populations of “phenotypically abnormal” γδ Tc in the blood.

A rare case of hepatosplenic gamma-delta T-cell lymphoma and secondary hemophagocytic lymphohistiocytosis

Hepatosplenic gamma-delta T-cell lymphoma with concurrent hemophogocytic lymphohistiocytosis is a rare but well-recognized clinical scenario, associated with a grim prognosis. Clinicians must be aware of this aggressive type of lymphoma so that a prompt diagnosis can be made with timely initiation of systemic therapy and referral for bone marrow transplant.

Collapsing glomerulonephritis with podocyte markers in hemophagocytic syndrome secondary to hepatosplenic T-cell lymphoma

The hemophagocytic syndrome is a serious clinical-histological entity secondary to different diseases. Collapsing glomerulonephritis is a proliferative podocytopathy that usually has an unfavorable renal prognosis. We present a case in which both entities were associated, which is an infrequent form of hepatosplenic T-cell lymphoma. In addition, we review the role of the markers of podocyte dedifferentiation in this glomerulopathy and its pathophysiology and treatment.

Hepatosplenic γδ T-cell lymphoma of two adolescents: Case report and retrospective literature review in children, adolescents, and young adults

HSTCL is a highly aggressive malignancy with a poor prognosis. Case series and accounts have reported the use of different chemotherapy regimens with diverse patient outcomes. Most long-term survivors had undergone high-dose chemotherapy with autologous or allogeneic HCT. We describe two pediatric patients with HSTCL who were treated with chemotherapy followed by allogeneic HCT. Both patients are alive and in complete remission 2 and 8 years after therapy. Multiagent chemotherapy followed with allogeneic HCT seems to provide patients who have chemotherapy-sensitive disease a long-term disease-free survival.

γδ T-Cell Acute Lymphoblastic Leukemia/Lymphoma: Discussion of Two Pediatric Cases and Its Distinction from Other Mature γδ T-Cell Malignancies

Gamma delta (γδ) T-cell antigen receptor (TCR) expression and its related T-cell differentiation are not commonly reported in T-cell acute lymphoblastic leukemia/lymphoma (T-ALL). Here we report two pediatric T-ALL cases and present their clinical features, histology, immunophenotypes, cytogenetics, and molecular diagnostic findings. The first patient is a two-year-old girl with leukocytosis, circulating lymphoblasts, and a cryptic insertion of a short-arm segment at 10p12 into the long-arm segment of 11q23 resulting in an MLL and AF10 fusion transcript, which may be the first reported in γδ T-ALL. She responded to the chemotherapy protocol poorly and had persistent diseases. Following an allogeneic bone marrow transplant, she went into remission. The second patient is an eleven-year-old boy with a normal white cell count, circulating blasts, and a normal karyotype, but without any immature cellular markers by flow cytometric analysis. He responded to the chemotherapy well and achieved a complete remission. These cases demonstrate the diverse phenotypic, cytogenetic, and molecular aspects of γδ T-ALL. Early T-precursor- (ETP-) ALL and their differential diagnosis from other mature γδ T-cell leukemia/lymphomas are also discussed.

Safety of treatments for inflammatory bowel disease: Clinical practice guidelines of the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD)

Inflammatory bowel diseases are chronic conditions of unknown etiology, showing a growing incidence and prevalence in several countries, including Italy. Although the etiology of Crohn's disease and ulcerative colitis is unknown, due to the current knowledge regarding their pathogenesis, effective treatment strategies have been developed. Several guidelines are available regarding the efficacy and safety of available drug treatments for inflammatory bowel diseases. Nevertheless, national guidelines provide additional information adapted to local feasibility, costs and legal issues related to the use of the same drugs. These observations prompted the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) to establish Italian guidelines on the safety of currently available treatments for Crohn's disease and ulcerative colitis. These guidelines discuss the use of aminosalicylates, systemic and low bioavailability corticosteroids, antibiotics (metronidazole, ciprofloxacin, rifaximin), thiopurines, methotrexate, cyclosporine A, TNFα antagonists, vedolizumab, and combination therapies. These guidelines are based on current knowledge derived from evidence-based medicine coupled with clinical experience of a national working group.

Hepatosplenic T-cell lymphoma in a 47-year-old Crohn’s disease patient on thiopurine monotherapy

Hepatosplenic T-cell lymphoma (HSTCL) is a rare non-Hodgkin lymphoma with a high mortality rate. Higher incidence is reported in patients with inflammatory bowel disease, specifically in male patients that are younger than 35 years, and have been treated with thiopurine and tumor necrosis factor (TNF)-α inhibitor combination therapy for over 2 years. In this case report we describe a 47-year-old patient with Crohn’s disease (CD) who developed HSTCL after having been treated with thiopurine monotherapy for 14 years. To our best knowledge, only eleven cases exist of patients with CD who developed HSTCL while on thiopurine monotherapy. We report the first patient with CD, older than 35 years, who developed HSTCL while on thiopurine monotherapy. This emphasizes that HSTCL risk is not limited to young men receiving both thiopurines and TNF-α inhibitors.

Two Cases of Hepatosplenic T-Cell Lymphoma in Adolescents Treated for Autoimmune Hepatitis

We report the first 2 cases of hepatosplenic T-cell lymphoma in adolescents diagnosed with autoimmune hepatitis under long-term treatment with azathioprine. Patients presented with fatigue, hepatosplenomegaly, and pancytopenia. The diagnosis could be confirmed performing biopsies of liver and spleen or bone marrow, which demonstrated infiltration of neoplastic T lymphocytes with the typical phenotype with both markers, CD56(+) and TCRγδ(+) Thus, these cases emphasize the need to constantly reevaluate the administered dose and duration of thiopurines for autoimmune hepatitis, especially in adolescents.

Rare Pediatric Non-Hodgkin Lymphomas: A Report From Children's Oncology Group Study ANHL 04B1

BACKGROUND

Non-Hodgkin lymphoma (NHL) is a relatively common malignancy in pediatric patients; however, a small subgroup have unusual lymphoma subtypes for the pediatric population.

PROCEDURE

The Children's Oncology Group Rare and Cutaneous NHL registry's (protocol ANHL 04B1) main objectives were to determine the pathologic, biologic, and clinical features of rare and cutaneous pediatric NHL and establish a bank of centrally reviewed tissue specimens. We report the clinical data, treatment data, and outcome for rare pediatric NHL.

RESULTS

In 101 lymphomas, there is a 97.8% concordance between the reviewing study pathologists and an 87.6% concordance between the central and institutional pathology review. Samples in the specimen bank include primary tumor tissue that is snap frozen, in paraffin blocks, or H&E-stained and unstained paraffin slides as well as blood, serum, and bone marrow. This descriptive analysis shows that children with pediatric follicular lymphoma, mucosa-associated lymphoid tissue, nodal marginal zone lymphoma, primary cutaneous, primary central nervous system lymphoma, and subcutaneous panniculitis-like T-cell lymphomas have 100% survival at a median of 2 years from enrollment. There are early deaths, mostly from progressive disease, in subjects with peripheral T-cell (not otherwise specified), NKT, and hepatosplenic T-cell lymphomas.

CONCLUSIONS

This registry provides high-quality biologic specimens with clinical data to investigators working on the biology of these unusual pediatric diseases.

Hepatosplenic T-cell lymphoma with aberrant expression of serum β-HCG: a case report

BACKGROUND

Peripheral T-cell lymphomas (PTCL) represent a heterogeneous group of hematologic malignancies frequently presenting at advanced stage of diagnosis.

METHODS

We report a case of PTCL with an uncommon and aggressive onset with disseminated intravascular coagulation (DIC).

RESULTS

Laboratory findings revealed an aberrant expression of β subunit of human chorionic gonadotropin (β-HCG). Other than for determination of pregnancy, β-HCG is regularly found as a tumor marker in germ cell tumors with trophoblastic differentiation and its aberrant expression has been reported in the literature in other neoplastic conditions only in the context of case reports.

CONCLUSIONS

In hematologic malignancies, β-HCG expression has been described only in sporadic cases. Awareness of this feature could avoid diagnostic delay in such an aggressive disease.

Cutaneous Involvement in a Case of Intravascular T-Cell Lymphoma With a γδ Phenotype

Intravascular lymphomas (IVL) are uncommon variants of extranodal non-Hodgkin which are usually difficult to diagnose because of their lack of clinical uniformity. Most cases are of B-cell differentiation followed by natural killer/T-cell differentiation and underlying CD30 lymphoproliferative conditions. Epstein-Barr virus is pathogenically related in most of the natural killer/T-cell variants, and the skin is a common site of presentation noted in approximately 40% of cases. Recently, cases with uncommon phenotypes have been described, expanding our understanding of the pathogenesis of this condition. In this report, we describe a 67-year-old man with a 3-month history of constitutional symptoms associated with linear purpuric macules on the trunk, pancytopenia, and high levels of serum lactate dehydrogenase. He had been followed for longstanding adenopathy and hepatosplenomegaly. Skin biopsy demonstrated a intravascular lymphocytic proliferation with positivity for CD3, CD2, CD5, and γδ T-cell receptor marker; in situ hybridization Epstein-Barr virus RNA was negative. The patient was subsequently treated with chemotherapy and allogenic stem cell transplant. He remains in complete remission 6 months posttransplant. Although the presence of hepatosplenomegaly led to consideration of a hepatosplenic T-cell lymphoma, it was pre-existing for several years making the diagnosis doubtful. To our knowledge, this is the first case report of an IVL γδ T-cell lymphoma.

Peripheral T-cell and NK cell lymphoproliferative disorders: cell of origin, clinical and pathological implications

T-cell lymphoproliferative disorders are a heterogeneous group of neoplasms with distinct clinical-biological properties. The normal cellular counterpart of these processes has been postulated based on functional and immunophenotypic analyses. However, T lymphocytes have been proven to be remarkably capable of modulating their properties, adapting their function in relationship with multiple stimuli and to the microenvironment. This impressive plasticity is determined by the equilibrium among a pool of transcription factors and by DNA chromatin regulators. It is now proven that the acquisition of specific genomic defects leads to the enforcement/activation of distinct pathways, which ultimately alter the preferential activation of defined regulators, forcing the neoplastic cells to acquire features and phenotypes distant from their original fate. Thus, dissecting the landscape of the genetic defects and their functional consequences in T-cell neoplasms is critical not only to pinpoint the origin of these tumors but also to define innovative mechanisms to re-adjust an unbalanced state to which the tumor cells have become addicted and make them vulnerable to therapies and targetable by the immune system. In our review, we briefly describe the pathological and clinical aspects of the T-cell lymphoma subtypes as well as NK-cell lymphomas and then focus on the current understanding of their pathogenesis and the implications on diagnosis and treatment.

Childhood Hepatosplenic T-cell Lymphoma with Skin Involvement

BACKGROUND

Hepatosplenic T-cell lymphoma is a rare malignancy in childhood.

CASE CHARACTERISTICS

A 12-year-old boy who presented a pyrexia of unknown origin, multiple skin and lesions and marked hepatosplenomegaly.

OBSERVATION

Bone marrow aspirate cytology showed no blast cells. Splenectomy was done, and spleen showed infiltration with atypical lymphoid cells positive for CD3, CD8 and T-cell-restricted intracellular antigen.

OUTCOME

The skin rash of patient subsided with chemotherapy.

MESSAGE

Skin involvement may be an unusual clinical manifestation of hepatosplenic T-cell lymphoma.

18F-FDG PET/CT in Hepatosplenic Gamma-Delta T-Cell Lymphoma

Hepatosplenic T-cell lymphoma (HSTCL) is a rare and often difficult-to-diagnose subtype of lymphoma that can occur in the chronically immunosuppressed patient. We present the typical FDG PET/CT findings of HSTCL in a renal transplant recipient. The whole-body metabolic and morphologic information provided by FDG PET/CT can be of great additional value in establishing this diagnosis, thus allowing for a timely start of treatment.

Uncommon non-Hodgkin lymphomas of childhood: pathological diagnosis, clinical features and treatment approaches

We provide a review of the pathological and clinical features for uncommon B-cell and T-cell lymphomas of childhood with a specific focus on advances in treatment approaches and outcomes. There is clearly a need for prospective investigation of both the clinical and biological features of the uncommon non-Hodgkin lymphoma subtypes in childhood. These results should lead to more uniform and more effective treatment approaches.

Pathology of T-cell lymphomas: diagnosis and biomarker discovery

T-cell lymphomas are a group of predominantly rare hematologic malignancies that tend to recapitulate different stages of T-cell development, in a similar way that B-cell lymphomas do. As opposed to B-cell lymphomas, the understanding of the biology and the classification of T-cell lymphomas are somewhat rudimentary, and numerous entities are still included as 'provisional categories' in the World Health Classification of hematolopoietic malignancies. A relevant and useful classification of these disorders have been difficult to accomplish because of the rarity nature of them, the relative lack of understanding of the molecular pathogenesis, and their morphological and immunophenotypical complexity. Overall, T-cell lymphomas represent only 15 % of all non-Hodgkin lymphomas. This review is focused on addressing the current status of the categories of mature T-cell leukemias and lymphomas (nodal and extranodal) using an approach that incorporates histopathology, immunophenotype, and molecular understanding of the nature of these disorders, using the same philosophy of the most recent revised WHO classification of hematopoietic malignancies.

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.

Hemophagocytic lymphohistiocytosis associated with hepatosplenic T-cell lymphoma: case report

Hepatosplenic T-cell lymphoma (HSTCL) is a rare non-Hodgkin lymphoma, marked by liver, spleen, and bone marrow sinusoidal infiltration, with an aggressive clinical course, which represents a difficult diagnostic task for clinicians and pathologists. Another equally severe and challenging condition is the hemophagocytic lymphohistiocytosis (also called hemophagocytic syndrome [HS]), which is often associated with hematologic malignancies and infectious diseases. The authors report the case of a 56-year-old woman diagnosed with HSTCL based on bone marrow aspirate flow cytometry and skin biopsy. The patient underwent a cycle of chemotherapy but the outcome was unfavorable with multiple organ failure. The laboratory analysis was consistent with HS. The autopsy confirmed both the remaining lymphoma in the pulmonary vessels and the hemophagocytic cells in the spleen and bone marrow.

Challenges and new prospects in hepatosplenic γδ T-cell lymphoma

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of lymphoid neoplasms characterized by aggressive clinical behavior and dismal prognosis. Hepatosplenic γδ T-cell lymphoma (γδ-HSTL) is a particular form of PTCL that arises from a small subset of γ/δ T-cell receptor-expressing lymphocytes. γδ-HSTL has a rapidly progressive course and poor outcome due also to its refractoriness to conventional chemotherapy regimens. The very low incidence of γδ-HSTL, along with its propensity to mimic different pathological entities, makes this lymphoma a true diagnostic challenge. In this review, we highlight the biological and clinical features of γδ-HSTL that contribute to making this lymphoma a mostly incurable disease. Moreover, we provide a new insight into the crosstalk between HSTL clones and the bone marrow, liver and spleen vascular microenvironment, in which neoplastic cells reside and proliferate. We further discuss γδ-HSTL associated molecules that might be proposed as potential targets for novel therapeutic approaches.

Infectious and malignant complications of TNF inhibitor therapy in IBD

Tumor necrosis factor (TNF) inhibitors are being increasingly utilized in the management of inflammatory bowel disease (IBD). Although the benefits associated with TNF inhibitor therapy are undeniable, concerns have been raised about the associated risk of infectious and malignant complications. In this narrative review, we will present the evidence from studies that have evaluated the association of TNF inhibitors and both overall and specific infections and malignancy. Overall, although TNF inhibitors may increase the risk of tuberculosis, varicella, and other opportunistic infections, there is little evidence suggesting that anti-TNF agents specifically raise the overall risk of serious infections. Similarly, there is little evidence that TNF antagonists raise the risk of developing malignancy over and above the risks from concomitant therapies and the underlying disease process. However, the risk of nonmelanoma skin cancers may be increased and that is further enhanced by use of combination TNF inhibitor and thiopurine therapy. The risk of non-Hodgkin's lymphoma is statistically increased among combination therapy users. The absolute risk remains a very small but feared risk. It is difficult to fully quantify the risk of these cancers among users of TNF inhibitor therapy in the absence of concurrent thiopurine therapy. We recommend that clinicians remain mindful about the potential risks of infectious and malignant complications in their IBD patients who are using TNF inhibitors, but that further research is required to better study these risks over the long-term course of therapy.

[Lymph node pathology - an update]

Immune suppression is a risk factor for malignant lymphoma development. Progress in medical science has increased the numbers of immunosuppressed patients due to organ transplantations or successful treatment of autoimmune diseases. Different forms of immune suppression and the respective lymphoma entities are discussed in this article. Another issue treated are gray zone lymphomas between Hodgkin's lymphoma and diffuse large B cell lymphoma. This category not only represents a diagnostic challenge but also represents more a true biological continuum.

Lymphoma and other lymphoproliferative disorders in inflammatory bowel disease: a review

The lymphoproliferative disorders (LDs) are a heterogeneous group of at least 70 conditions that result from the clonal proliferation of B, T, and NK cells. Inflammatory bowel disease (IBD)-associated lymphomas are typically B-cell LD, while T-cell or Hodgkin's lymphomas are rare. In IBD patients not on immunosuppression, the risk of LD seems to be similar or slightly higher than the background population risk. Thiopurine therapy is associated with an increased risk: the relative risk is increased four- to sixfold and the absolute risk varies between 1 in 4000-5000 for those aged 20-29 to 1 in 300-400 in those over 70. It is difficult to quantify the risk of anti- tumor necrosis factor (TNF) therapy alone; however, it appears to be less than for thiopurines alone. There is particular concern regarding the development of post-transplant-like LD in those with latent epstein-barr virus (EBV) infection exposed to immunosuppressives, the occurrence of hepatosplenic T cell lymphoma in patients treated with combination anti-TNF and thiopurine therapy, and the development of hemophagocytic lymphohistiocytosis in those who acquire a primary EBV or other infections while on immunosuppressive medication. There are currently no guidelines for monitoring EBV (or other virus) status in patients on immunosuppression, although it could be used to monitor those who have a prior history of lymphoma and are about to start a thiopurine or anti-TNF agent. In discussing the risks of lymphoproliferative disorders associated with agents used for the treatment of IBD, patients can often be reassured that the benefits of such therapy still outweigh the small, but real, risks.

Lymphoma-like T cell infiltration in liver is associated with increased copy number of dominant negative form of TGFβ receptor II

Hepatosplenic T cell lymphoma (HSTCL) is a distinct and lethal subtype of peripheral T cell lymphoma with an aggressive course and poor outcome despite multiagent chemotherapy. Contradictory literature, an unknown etiology, and poor response to treatment highlight the need to define the malignant process and identify molecular targets with potential for successful therapeutic interventions. Herein, we report that mice homozygously expressing a dominant negative TGFβRII (dnTGFβRII) under the control of the CD4 promoter spontaneously develop lymphoma-like T cell infiltration involving both spleen and liver. Splenomegaly, hepatomegaly and liver dysfunction were observed in homozygous dnTGFβRII mice between 10 weeks and 10 months of age associated with a predominant infiltration of CD4⁻CD8⁻TCRβ⁺NK1.1⁺ or CD8⁺TCRβ⁺NK1.1⁻ T cell subsets. Notch 1 and c-Myc expression at the mRNA levels were significantly increased and positively correlated with the cell number of lymphoid infiltrates in the liver of dnTGFβRII homozygous compared to hemizygous mice. Further, 2×10⁴ isolated lymphoma-like cells transplant disease by adoptive cell transfers. Collectively, our data demonstrate that increased copy number of dnTGFβRII is critical for development of lymphoma-like T cell infiltration.