Hepatosplenic gamma-delta T-cell lymphoma: clinicopathological features and treatment

Current and upcoming treatment approaches to uncommon subtypes of PTCL (EATL, MEITL, SPTCL, and HSTCL)

ABSTRACT

Rare subtypes of peripheral T-cell lymphoma (PTCL) including enteropathy-associated T-cell lymphoma (EATL), monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), subcutaneous panniculitis-like T-cell lymphoma (SPTCL), and hepatosplenic T-cell lymphoma (HSTCL) are underrepresented in most registries and clinical studies. Most of the literature is obtained from small case series, single-institution retrospective studies, and subgroup analyses of the largest studies with few recent and ongoing exceptions. Although the pathogenesis and biology of these entities have yet to be fully elucidated, global efforts by the scientific community have started to shed some light on the most frequently deregulated pathways. In this review, we highlight the most pertinent clinical and pathologic features of rare subtypes of PTCL including EATL/MEITL, SPTCL, and HSTCL. We also summarize the results of recent developments identifying potential targets for novel therapeutic strategies based on molecular studies. Finally, we highlight the underrepresentation of these rare subtypes in most clinical trials, making evidence-based therapeutic decisions extremely challenging.

Ethnicity and socio-economic status affects the incidence and survival of hepatosplenic T-cell lymphoma

To address the lack of contemporary population-based epidemiological studies of hepatosplenic T-cell lymphoma (HSTCL), we undertook a population-based study of ICD-O-3-coded HSTCL in England. We used the National Cancer Registration Dataset and linked datasets on hospital admissions, Systemic Anti-Cancer Therapy, socio-demographics, comorbidities and death, identifying cases from 1 January 2013 to 31 December 2019 with survival data up to 5 January 2021. Crude and directly age-standardised incidence rates per million persons per year were calculated. Crude and adjusted incidence rate ratios compared incidence between groups using Poisson regression. A Cox proportional hazards model estimated mortality risks adjusted for age, sex, ethnicity, deprivation and allogenic stem cell transplant (allo-SCT; time varying). We identified 44 patients, mean age 42 years. Median survival was 11 months, and 1 and 5 year survivals were 48% (95% CI 29%-43%) and 22% (95% CI 12%-42%) respectively. The age-standardised incidence was 0.1 per million/year. Incidence was higher in areas with greater deprivation (0.15 per million/year), and more cases than expected were in non-White patients (39%). Non-Whites had a twofold increased risk of death (adjusted hazard ratio 2.21 [95% CI 1.03-4.78]) even after adjusting for deprivation, younger age and allo-SCT. In conclusion, ethnicity and socio-economic status affect both the incidence and survival of HSTCL.

A US Multicenter Collaborative Study on Outcomes of Hematopoietic Cell Transplantation in Hepatosplenic T-Cell Lymphoma

Hepatosplenic T-cell lymphoma (HSTCL) is a rare and aggressive type of peripheral T-cell lymphoma with median overall survival (OS) of approximately 1 year. Data on the effectiveness of hematopoietic cell transplantation (HCT) is limited, as is the choice between autologous HCT (auto-HCT) and allogeneic HCT (allo-HCT) in the treatment of this disease. To evaluate the outcome of patients with HSTCL who underwent either auto-HCT or allo-HCT, we performed a multi-institutional retrospective cohort study to assess outcomes of HCT in HSTCL patients. Fifty-three patients with HSTCL were included in the study. Thirty-six patients received an allo-HCT and 17 received an auto-HCT. Thirty-five (66%) were males. Median age at diagnosis was 38 (range 2 to 64) years. Median follow-up for survivors was 75 months (range 8 to 204). The median number of prior lines of therapy was 1 (range 1 to 4). Median OS and progression-free survival (PFS) for the entire cohort were 78.5 months (95% CI: 25 to 79) and 54 months (95% CI: 18 to 75), respectively. There were no significant differences in OS (HR: 0.63, 95% CI: 0.28 to 1.45, P = .245) or PFS (HR: 0.7, 95% CI: 0.32 to 1.57, P = .365) between the allo-HCT and auto-HCT groups, respectively. In the allo-HCT group, the 3-year cumulative incidence of relapse was 35% (95% CI: 21 to 57), while 3-year cumulative incidence of NRM was 16% (95% CI: 7 to 35). In the auto-HCT group, the 3-year cumulative incidence of relapse and NRM were 43% (95% CI: 23 to 78) and 14% (95% CI: 4 to 52), respectively. Both Auto-HCT and Allo-HCT are effective consolidative strategies in patients with HSTCL, and patients should be promptly referred for HCT evaluation.

Allo-HSCT with TBI-based preconditioning for hepatosplenic T-cell lymphoma: two case reports and systematic review of literature

Hepatosplenic T cell lymphoma (HSTCL) is a particularly difficult-to-treat form of lymphoma, with many patients exhibiting primary resistance to chemotherapy. At present, no effective strategy for treating relapsed and refractory HSTCL has been established, with treatment being hampered by questions of how best to overcome chemoresistance to allow patients to attain more durable therapeutic benefits. While there have been marked advances in immunotherapy, allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains one of the primary approaches to curing HSTCL. Of patients who undergo immunochemotherapeutic treatment, many are resistant to conventional chemotherapeutic drugs yet remain sensitive to radiotherapy. We selected to employ a transplant pretreatment regimen consisting of total -body irradiation (TBI) and administered this regimen to two patients with HSTCL. Both patients achieved complete remission (CR) after transplantation, demonstrating extended periods without disease recurrence. We systematic reviewed previously published instances involving allo-HSCT in patients with HSTCL. We have found a total of 67 patients who have received allo-HSCT. In general, age<45 and the status of CR at HSCT may have a more favorable prognosis. Although the impact of TBI on prognosis was not found to be substantial, patients in the TBI group had higher 3-year overall survival (66.7% vs. 71.1%) and 5-year overall survival (58.4% vs. 71.1%) compared to patients in the non-TBI group. In addition, the relapse rate of the TBI group is approximately half that of the non-TBI group. This regimen is well tolerated and associated with low recurrence rates or complications, suggesting that it represents a viable pretreatment regimen for young HSTCL patients undergoing allogeneic HSCT.

Biology and genetics of extranodal mature T-cell and NKcell lymphomas and lymphoproliferative disorders

The extranodal mature T-cell and NK-cell lymphomas and lymphoproliferative disorders represent a unique group of rare neoplasms with both overlapping and distinct clinicopathological, biological, and genomic features. Their predilection for specific sites, such as the gastrointestinal tract, aerodigestive tract, liver, spleen, and skin/soft tissues, underlies their classification. Recent genomic advances have furthered our understanding of the biology and pathogenesis of these diseases, which is critical for accurate diagnosis, prognostic assessment, and therapeutic decision-making. Here we review clinical, pathological, genomic, and biological features of the following extranodal mature T-cell and NK-cell lymphomas and lymphoproliferative disorders: primary intestinal T-cell and NK-cell neoplasms, hepatosplenic T-cell lymphoma, extranodal NK/T-cell lymphoma, nasal type, and subcutaneous panniculitis-like T-cell lymphoma.

Few and far between: clinical management of rare extranodal subtypes of mature T-cell and NK-cell lymphomas

While all peripheral T-cell lymphomas are uncommon, certain subtypes are truly rare, with less than a few hundred cases per year in the USA. There are often no dedicated clinical trials in these rare subtypes, and data are generally limited to case reports and retrospective case series. Therefore, clinical management is often based on this limited literature and extrapolation of data from the more common, nodal T-cell lymphomas in conjunction with personal experience. Nevertheless, thanks to tremendous pre-clinical efforts to understand these rare diseases, an increasing appreciation of the biological changes that underlie these entities is forming. In this review, we attempt to summarize the relevant literature regarding the initial management of certain rare subtypes, specifically subcutaneous panniculitis-like T-cell lymphoma, hepatosplenic T-cell lymphoma, intestinal T-cell lymphomas, and extranodal NK/T-cell lymphoma. While unequivocally established approaches in these diseases do not exist, we make cautious efforts to provide our approaches to clinical management when possible.

Felty's syndrome

Felty's syndrome was first described in 1924 by the US-American physician Augustus Roi Felty as a triad of rheumatoid arthritis, splenomegaly and leucopenia. Even nearly 100 years later, this rare syndrome is still paralleled by diagnostic and therapeutic challenges and its pathogenesis is incompletely understood. Neutropenia with potentially life-threatening infections is the main problem and several pathomechanisms like Fas-mediated apoptosis, anti-neutrophil antibodies, anti-G-CSF antibodies, neutrophil consumption in the context of NETosis and suppression of granulopoiesis by T-LGLs have been suggested. Felty's syndrome has various differential diagnoses as splenomegaly and cytopenia are common features of different infectious diseases, malignancies and autoimmune disorders. Additionally, benign clonal T-/NK-LGL lymphocytosis is increasingly noticed in Felty's syndrome, which further complicates diagnosis. Today's treatment options are still sparse and are largely based on case reports and small case series. Methotrexate is the mainstay of therapy, followed by rituximab, but there is less evidence for alternatives in the case of adverse reactions or failure of these drugs. This article gives an updated review about Felty's syndrome including its pathogenesis and treatment options.

SOHO State of the Art Updates and Next Questions | Challenging Cases in Rare T-Cell Lymphomas

Mature T- and NK-cell neoplasms (MTNKN) collectively represent a rare disorder, representing less than 15% of all non-Hodgkin lymphoma (NHL) cases and qualifying for orphan disease designation by the U.S. Food and Drug Administration (FDA). These consist of 9 families in the fifth revised WHO classification of lymphoid neoplasms, which are made up of over 30 disease subtypes, underscoring the heterogeneity of clinical features, molecular biology, and genetics across this disease group. Moreover, the 5 most common subtypes (peripheral T-cell lymphoma, not otherwise specified; nodal TFH cell lymphoma, angioimmunoblastic type; extranodal NK-cell/T-cell lymphoma; adult T-cell leukemia/lymphoma; and ALK-positive or -negative anaplastic large cell lymphoma) comprise over 75% of MTNKN cases, so other subtypes are exceedingly rare in the context of all NHL diagnoses and consequently often lack consensus on best practices in diagnosis and management. In this review, we discuss the following entities-enteropathy-associated T-cell lymphoma (EATL), monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), hepatosplenic T-cell lymphoma (HSTCL), subcutaneous panniculitis-like T-cell lymphoma (SPTCL), and primary cutaneous ɣδ T-cell lymphoma (PCGD-TCL) - with an emphasis on clinical and diagnostic features and options for management.

Retrospective analysis of diagnosis and therapeutic strategies for patients with hepatosplenic T cell lymphoma

Hepatosplenic T cell lymphoma (HSTCL) is a rare and aggressive lymphoma with no standard treatment and poor treatment response. From 2001-2021, 20 from a lymphoma cohort of 7247 patients (0.27%) were diagnosed with HSTCL at Samsung Medical Center. The median age at the time of diagnosis was 37.5 (range, 17-72) years, and 75.0% of patients were male. Most patients had B symptoms, hepatomegaly, and splenomegaly. Lymphadenopathy was found in only 31.6% of patients, and increased PET-CT uptake was found in 21.1% of patients. Thirteen patients (68.4%) expressed T cell receptor (TCR) γδ, and 6 patients (31.6%) expressed TCRαβ. The median progression-free survival (PFS) for the entire cohort was 7.2 months (95% CI, 2.9-12.8), and the median overall survival (OS) was 25.7 months (95% CI, not calculated). In subgroup analysis, the overall response rate (ORR) was 100.0% in the ICE/Dexa group and 53.8% in the anthracycline-based group, and the complete response rate was 83.3% in the ICE/Dexa group and 38.5% in the anthracycline-based group. The ORR was 50.0% in the TCRαβ group and 83.3% in the TCRγδ group. The OS was not reached in the autologous hematopoietic stem cell transplantation (HSCT) group and was 16.0 months (95% CI, 15.1-16.9) in the non-transplant group at the data cutoff time (P value 0.015). In conclusion, HSTCL is rare but has a very poor prognosis. The optimal treatment strategy is not defined. More genetic and biological information is needed.

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.

HLA Fully-Mismatched Sibling-Derived CD7 CAR-T Therapy Bridging to Haploidentical Hematopoietic Stem Cell Transplantation for Hepatosplenic γδ T-cell Lymphoma

While chimeric antigen receptor (CAR)-T-cell therapy has demonstrated remarkable effectiveness in the treatment of B-cell lymphomas and leukemias, research on T-cell malignancies is still limited. Here, we reported a patient with hepatosplenic γδ T-cell lymphoma refractory to multiple lines of chemotherapy, who eventually achieved first complete remission with flow cytometry-confirmed minimal residual disease negativity after human leukocyte antigen (HLA) fully-mismatched sibling-derived CD7 CAR-T therapy. However, given the allogeneic nature, CAR-T cells dropped rapidly after a peak of 83.4% of circulating T-cells. Cytokine release syndrome, cytopenia, and infections occurred but were manageable after treatments. After the consolidative haploidentical hematopoietic stem cell transplantation (HSCT), the patient remained in remission at the end of the follow-up (13 months post-CAR-T infusion). This is the first case of relapsed/refractory hepatosplenic γδ T-cell lymphoma who achieved lasting CR after HLA fully-mismatched sibling-derived CD7 CAR-T therapy bridging to haploidentical HSCT.

Prognostic significance of pretreatment 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in patients with primary T cell lymphomas

OBJECTIVE

T cell lymphomas are associated with an aggressive worse prognosis. This study is designed to assess T cell lymphomas using 18F-FDG PET/CT.

METHODS

Sixty-four patients with newly diagnosed T cell lymphomas underwent PET/computed tomography (PET/CT) scans, 47 cases who were fully followed up were retrospectively reviewed and analyzed. Overall survival (OS) and progression-free survival (PFS) were recorded for prognosis. We measured the maximum standardized uptake value (SUVmax) in all cases, analyzed the correlation between SUVmax and survival and other clinicopathologic parameters. Kaplan-Meier log-rank tests were then used to compare the survival of high and low PET/CT parameter groups, and multivariate Cox proportional hazards regression analysis was carried out to identify predictors of OS and PFS.

RESULTS

With a median follow-up of 26.5 (range 0.7-117.5) months, the 1-, 2- and 3-year OS were 75.6, 61.7 and 49.2%, and PFS were 49.3, 39.9 and 29.9%, respectively in 47 patients. Among them, 33 cases progressed with a median time of 9.5 (0.7-115.0) months, and 26 patients died with a median survival time of 26.5 (0.7-117.5) months. Multivariate analysis showed the following independent prognostic factors for OS: age >60 years (P = 0.002), SUVmax >9.7 (P = 0.009) and extranodal involvement of more than one site (P = 0.018). In addition, lactate dehydrogenase level (P = 0.003) and B symptoms (P = 0.018) were independent risk factors for PFS.

CONCLUSION

Pretherapy SUVmax may serve as an independent predictor of outcome in patients with newly diagnosed T cell lymphomas.

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.

Recent advances in T-cell lymphoid neoplasms

T Cells comprise many subtypes of specified lymphocytes, and their differentiation and function take place in different tissues. This cellular diversity is also observed in the multiple ways T-cell transformation gives rise to a variety of T-cell neoplasms. This review covers the main types of T-cell malignancies and their specific characteristics, emphasizing recent advances at the cellular and molecular levels as well as differences and commonalities among them.

Survival Analysis of Hepatosplenic T Cell Lymphoma: A Population-Based Study Using SEER

Purpose

Hepatosplenic T cell lymphoma (HSTCL) is a rare tumor that lacks data to guide management decisions. To shed light on the nature and therapy of the entity, we conducted this study.

Patients and Methods

We retrospectively reviewed patients diagnosed with HSTCL between 1975 and 2016 in the Surveillance, Epidemiology, and End Results (SEER) database to analyze the clinical characteristics and survival outcome compared with PTCL-NOS and ALK+ ALCL.

Results

A total of 123 HSTCLs were included in the analysis. Most patients were aged ≤60 years (81.3%) and had a male predominance (69.1%). Organs with lymphoma infiltration of HSTCL were more common in the spleen (98.4%). The 1-year, 3-year, and 5-year overall survival (OS) rates in the entire HSTCL cohort were 56.9% (95% CI, 47.5–66.3%), 37.6% (95% CI, 28.0–47.2%), and 31.6.0% (95% CI, 22.2–41.0%), respectively. The overall survival (OS) of HSTCL patients was similar to that of PTCL-NOS patients (P = 0.128) but worse than that of patients with ALK+ ALCL (P < 0.001). The disease-specific survival (DSS) of HSTCL patients was worse than that of PTCL-NOS and ALK+ ALCL patients (P < 0.05). The same tendency was found in the matched data set. Cox regression analyses indicated that the use of chemotherapy combined with topical treatment may improve the survival of patients with HSTCL.

Conclusion

A higher proportion of young patients and a strong male predominance were found in HSTCL. Chemotherapy combined with topical treatment may be an optional regimen. Further studies are needed to intensify efforts in dealing with this rare but unfavorable disease.

Heterogeneous Manifestations of Posttransplant Lymphoma in Renal Transplant Recipients: A Case Series

Posttransplant lymphoproliferative disorder (PTLD) occurs in 1% to 3% of adult renal transplant recipients (RTRs). PTLD has a heterogeneous presentation and is often associated with Epstein-Barr virus (EBV) and immunosuppression. We present a descriptive case series of 16 RTRs who demonstrate a variety of PTLD manifestations. Fifty-six percent received rabbit antithymocyte globulin induction, and 37.5% received basiliximab. Maintenance immunosuppression included glucocorticoids, tacrolimus, and mycophenolate mofetil. Median time from transplantation to PTLD diagnosis was 96.5 months. PTLD involved a single site in 44% of RTRs and multiple sites in 56%. PTLD was localized to the gastrointestinal tract in 9 RTRs, in lymph nodes in 9, central nervous system in 4, bone marrow in 3, skin in 3, lungs in 2, perinephric space in 2, mediastinum in 1, and native kidney in 1. PTLD was EBV positive in 8 RTRs, monomorphic/monoclonal in 14, and of B-cell lineage in 13. Three RTRs had T-cell PTLD. Immunosuppressive agents, except glucocorticoids, were discontinued at diagnosis. Treatment was chemotherapy either alone (in 14 RTRs) or in combination with radiation. Complete remission was achieved in 62.5% of RTRs. Renal dysfunction developed in 62.5% of RTRs, and 4 received dialysis. The overall mortality rate was 62.5%, with median time of death 6.5 months after diagnosis. PTLD that was EBV negative and had T-cell involvement presented with aggressive disease and a higher mortality. Clinicians should be aware of the various PTLD manifestations. Early diagnosis and a multidisciplinary approach to treatment is crucial for improved patient outcomes.

Characteristics of Lymphoma in Patients with Inflammatory Bowel Disease: A Systematic Review

BACKGROUND

Lymphoma is a dreaded complication of inflammatory bowel diseases [IBD]. Knowledge about lymphoma in patients with IBD is limited to epidemiological data and the description of risk factors. We performed a systematic review to describe the clinical characteristics and prognosis of lymphoma in patients with IBD.

METHODS

Electronic databases were searched up to June 1, 2020. All published clinical characteristics of lymphoma occurring in patients with IBD were collected.

RESULTS

Eleven studies were included. A total of 589 lymphomas were described in patients with IBD. As seen in de novo lymphoma, non-Hodgkin's lymphoma [NHL] was the most common histological subtype [83.9%]. Diffuse large B-cell lymphoma [DLBCL] and follicular lymphoma were the most well-represented NHL in patients with IBD [30% and 13% respectively]. Two main differences were observed in comparison with de novo lymphoma: primary intestinal lymphoma [PIL] represented a large proportion of lymphoma in patients with IBD [22-75%] whereas mucosa-associated lymphoid tissue [MALT] lymphoma was under-represented. Epstein-Barr virus [EBV]-positive status was observed in a large proportion of tumours [44-75%]. Survival data of lymphoma in patients with IBD were similar to those of de novo lymphoma.

DISCUSSION

This systematic review first highlights that PIL [especially DLBCL subtype] is significantly more frequent in patients with IBD and represents the most common entity. Conversely, MALT lymphoma is extremely rare in the IBD population. However, the overall quality of the evidence is low. Further studies are required to better define lymphoma characteristics in patients with IBD.

Clinical features and treatment outcomes of 14 patients with hepatosplenic γ δ T-cell lymphoma

BACKGROUND

Hepatosplenic γ δ T-cell lymphoma (HSTCL) is a rare subtype of peripheral T-cell lymphoma (PTCL) with aggressive clinical behavior. To date, no standard therapy for HSTCL has been established. This study analyzed the clinical features, treatment, and prognosis for patients with HSTCL to determine the best therapeutic approach.

METHODS

We reviewed the clinical characteristics, treatments, and responses to treatment of patients in our center between January 2001 and June 2021, and also reviewed related literature.

RESULTS

Median patient age was 38 years (range 16-60 years) and the patients included eight males and six females. HSTCL in these patients typically presented with B symptoms (71.4%), splenomegaly (100%), and hepatomegaly (50.0%), but lymphadenopathy was extremely rare. In these patients, routine laboratory testing showed elevated lactate dehydrogenase (71.4%), liver dysfunction (42.9%), and decreased fibrinogen (35.7%). In the induction phase, five of the 14 patients received chemotherapy regimens containing anthracycline (CHOP, or CHOP plus bortezomib or Chidamide), and six were treated with non-CHOP chemotherapy. Seven patients responded to induction treatment, four of whom received allogeneic hematopoietic cell transplantation and then achieved a complete response in the consolidation phase. survival time of patients who received alloHCT range from 10 to 27 months.

CONCLUSION

Hepatosplenic γ δ T-cell lacks a standard therapy and is often refractory to conventional chemotherapy regimens. Intensive induction chemotherapy followed by hematopoietic cell transplantation may improve the prognosis of HSTCL.

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.

Hypercalcaemia: An Extremely Rare Presentation of Hepatosplenic T-Cell Lymphoma

Hypercalcaemia is a frequent finding in malignancies including lymphomas. However, there are no reports of hypercalcaemia in hepatosplenic T-cell lymphoma (HSTCL). HSTCL is a rare and aggressive neoplasm which is usually difficult to diagnose. We present a case of HSTCL in which hypercalcaemia was the initial presentation.

LEARNING POINTS

Hepatosplenic T-cell lymphoma (HSTCL) is difficult to diagnose, has a poor prognosis and usually presents with hepatosplenomegaly, B symptoms and cytopenias.Hypercalcaemia is an extremely rare clinical presentation of HSTCL.Severe hypercalcaemia is a life-threatening condition and should always be corrected and investigated.

NCCN Guidelines Insights: T-Cell Lymphomas, Version 1.2021

Hepatosplenic T-cell lymphoma (HSTCL) is a rare subtype of T-cell lymphoma associated with an aggressive clinical course and a worse prognosis. HSTCL develops in the setting of chronic immune suppression or immune dysregulation in up to 20% of cases and is most often characterized by spleen, liver, and bone marrow involvement. Diagnosis and management of HSTCL pose significant challenges given the rarity of the disease along with the absence of lymphadenopathy and poor outcome with conventional chemotherapy regimens. These Guidelines Insights focus on the diagnosis and treatment of HSTCL as outlined in the NCCN Guidelines for T-Cell Lymphomas.

Outcomes of Hepatosplenic T-Cell Lymphoma: The Mayo Clinic Experience

BACKGROUND

Hepatosplenic T-cell lymphoma (HSTCL) is a rare subtype of peripheral T-cell lymphoma accounting for less than 1% of non-Hodgkin lymphomas. It is generally associated with poor prognosis.

PATIENTS AND METHODS

We performed a cohort study of patients with HSTCL treated at the Mayo Clinic between 1996 and 2020 exploring the clinical characteristics and therapeutic outcomes.

RESULTS

Twenty-two cases of HSTCL were identified with a median (range) age at diagnosis of 45.5 (15.5-80.6) years and a male predominance (15/22, 68.2%). Clinical characteristics include massive splenomegaly in 16 patients (73%), hepatic involvement in 13 (59%), and chronic immunosuppressed state in 8 (36%). Phenotypically, lymphoma cells had gamma/delta T-cell receptor expression in 18 (82%) and alpha/beta in 4 patients. Cytogenetic abnormalities included isochromosome 7q (i7q) in 8 (62%) of 13 and trisomy 8 in 4 (44%) of 9. The median (range) follow-up of surviving patients was 33 (2.5-137) months. The median progression-free and overall survival were 9.5 months (95% CI, 1.8, 16.3) and 12.4 months (95% CI, 4.9, 18.5), respectively. Long-term survival was seen in 4 (18%) of 22 patients, with survival of 55, 74, 95, and 137 months. Moreover, 3 of 4 long-term survivors had splenectomy as part of initial treatment, and 2 of 4 long-term survivors received an allogeneic hematopoietic cell transplant (allo-HCT).

CONCLUSION

Liver involvement and chronic immunosuppression were associated with shorter survival. Although splenectomy and allo-HCT have anecdotal benefit in the literature, our data do not show a statistically significant benefit of splenectomy and/or allo-HCT, likely as a result of our small sample size.

Hepatosplenic γ-δ T-Cell Lymphoma: Who Is on Your Speed Dial?

Hepatosplenic γ-δ T-cell lymphoma, an exceptionally uncommon subtype of peripheral T-cell lymphomas, commonly presents with advanced-stage disease manifesting with hepatosplenomegaly, cytopenias, and constitutional symptoms. Management of this subset is challenging as a result of the unique presentation and refractory nature to conventional treatment approaches. There is a lack of consensus guidelines for up-front induction strategies, and the role of consolidative autologous or allogeneic stem-cell transplantation is controversial. Prospective studies are lacking, and treatment is often guided by literature on the basis of case series or single-institution studies, lending to expert opinions influencing treatment paradigms.

Effect of chidamide on treating hepatosplenic T-cell lymphoma: A case report

BACKGROUND

Hepatosplenic T-cell lymphoma (HSTCL) is a rare subtype of non-Hodgkin’s lymphoma, which has an aggressive clinical course and an extremely poor prognosis. Chidamide is a novel, orally active, benzamide-type histone deacetylase (HDAC) inhibitor that has been used for peripheral T-cell lymphoma (PTCL) treatment. However, to date, there has been no report of the treatment and effect of the HDAC inhibitor chidamide in HSTCL, which is a special subtype of PTCL.

CASE SUMMARY

A 45-year-old male patient was admitted with splenomegaly and slight bicytopenia. He was diagnosed with HSTCL via splenectomy. The patient was treated with fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with high-dose methotrexate and cytarabine regiment as inductive therapy. Unfortunately, the disease progressed rapidly during chemotherapy before a suitable allogeneic gene transplant donor was found. The chidamide-combined chemotherapy regimen and single-drug oral maintenance regimen achieved complete remission, duration of response of 9 mo, and overall survival of 15 mo.

CONCLUSION

The novel agent chidamide can be used in HSTCL to achieve deep remission and improve the duration of response and overall survival.

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.

Role of Imaging in Diagnosis of a Rare Hepatosplenic Gamma Delta T-Cell Lymphoma during Pregnancy: A Case Report and Review of Literature

Hepatosplenic γδ T-cell lymphoma (HSTCL) is a very rare peripheral T-cell lymphoma characterized by extranodal infiltration of mature malignant post-thymic T-lymphocytes into sinusoids of the liver and spleen without lymphadenopathy and significant cytopenias. It is an aggressive form of lymphoma, resistant to the conventional chemotherapy. We report a case of HSTCL in pregnancy. Because this condition is an extremely aggressive and rare entity, data from these cases can help confirm the most suitable treatment regimen and timing of initiation. The role of ultrasound and magnetic resonance imaging in the diagnosis has been discussed. HSTCL is a rare entity of T-cell lymphoma, uncommon in female patients and very rarely reported during pregnancy.

T-cell lymphoproliferative processes in the spleen

T-cell lymphoproliferative processes in the spleen are rare and it is important to study normal T cell subsets in the spleen to understand the splenic milieu in which they arise. True malignant T-cell processes including hepatosplenic T-cell lymphoma and T-cell large granular lymphocytic leukemia occur in the spleen, but other atypical reactive T-cell proliferations and those of uncertain significance also have been described. Proper distinction of florid T cell responses from malignant T-cell neoplasms has important therapeutic implications for the patient.

Diagnostic and therapeutic splenectomy for splenic lymphomas: analysis of the National Cancer Data Base

OBJECTIVES

To examine the use of splenectomy, chemotherapy, and subsequent overall survival (OS) in contemporary patients with splenic lymphomas.

METHODS

We analyzed records of 6450 patients with various splenic lymphomas recorded in the National Cancer Data Base (2004-2013). Survival was compared using Mantel-Byer test to account for guarantee-time bias, stratified by age, sex, comorbidities, and lymphoma stage.

RESULTS

Splenectomy rate was overall 58%, and varied from 49% in splenic marginal zone (SMZL) to 77% in follicular lymphoma (FL). It significantly decreased across all histologies over time (overall from 69% in 2004, to 44% in 2013). Thirty-day mortality after splenectomy was 4%. Chemotherapy use varied from 40% in FL to 76% in diffuse large B-cell lymphoma (DLBCL), but increased significantly only for SMZL and T-cell lymphomas over time. Overall, 57% of splenectomies were performed as diagnostic procedures, which was significantly less common in academic hospitals (p < 0.0001). Following a diagnostic splenectomy, chemotherapy was not administered to 29% of patients with DLBCL, 49% with mantle cell, and 42% with T-cell lymphomas. Median OS ranged from 12.4 years for FL to 1.0 year for T-cell lymphomas. We found no association between performance of splenectomy and OS across all histologies. Patients with DLBCL who did not receive chemotherapy after a diagnostic splenectomy had significantly worse OS (p = 0.001). The association between post-splenectomy chemotherapy and OS was not observed in FL or SMZL.

CONCLUSION

many splenic lymphomas may be treated without surgery, but a high proportion of diagnostic splenectomies indicates an ongoing need for less invasive diagnostic modalities.

Hepatosplenic T cell lymphoma presenting as multiorgan failure

A 59-year-oldwoman presented with a 2-month history of malaise, abdominal distention and unintentional weight loss. She was initially managed as community acquired pneumonia with a suspicion of underlying chronic liver disease but she deteriorated rapidly into a multiorgan failure necessitating transfer to intensive care unit of a tertiary hospital. She was investigated with liver and bone marrow biopsy that confirmed the diagnosis of hepatosplenic T cell lymphoma. She was treated with cyclophosphamide, doxorubicin, vincristine, etoposide and prednisolone chemotherapy that was changed to salvage ifosfamide carboplatin etoposide (ICE) chemotherapy due to poor response with first-line chemotherapy and disease progression. Unfortunately, her disease progressed further and she opted for palliative management.

Successful Bridging Chemotherapy with Gemcitabine, Carboplatin, and Dexamethasone before Unrelated Stem Cell Transplantation for Hepatosplenic T-cell Lymphoma

A 45-year-old woman was diagnosed with hepatosplenic T-cell lymphoma (HSTCL), a rare subtype of peripheral T-cell lymphoma. She received different types of chemotherapy, but disease progression was observed. To reduce the tumor burden before an unrelated bone marrow transplantation, combination chemotherapy consisting of the gemcitabine, carboplatin, and dexamethasone (GCD) was administered as bridging therapy, resulting in a reduction in the number of lymphoma cells. We were then able to perform bone marrow transplantation. Although she experienced some adverse events, she successfully achieved long-term remission. We herein report a successful case of HSTCL treated with unrelated stem cell transplantation following the GCD regimen as bridging chemotherapy.

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.

Hepatosplenic T-Cell Lymphomas

Hepatosplenic T-cell lymphoma (HSTL) is a rare variant of extranodal peripheral T-cell lymphomas (PTCL), associated with aggressive disease course and a relentless track record for lethal outcomes. HSTL presents commonly in young men in their third or fourth decade. Of the known causes, immune dysregulation and immunosuppression are the key players in the pathogenesis of HSTL. Clinical manifestation includes hepatosplenomegaly, fevers, and weakness. Bone marrow involvement or organomegaly can cause cytopenias. Anthracycline-based regimens provide modest responses with most individuals dying within a year of diagnosis. Hematopoietic stem cell transplant (HSCT) can be offered to fit and eligible patients to prolong remissions. Disease relapse post chemotherapy has an aggressive phenotype, with limited salvage options available in the setting of declining performance status. Understanding the disease biology further to identify mechanistic-driven drug discovery could overcome the current limitations of existing therapeutic armamentarium.

Epidemiology and Pathology of T- and NK-Cell Lymphomas

PURPOSE

This review will describe and update readers on the recent changes in the 2017 WHO classification regarding peripheral T-cell lymphomas.

RECENT FINDINGS

Signficant advances in molecular studies have resulted in revisions to the classification as well as introduction to provisional entities such as breast implant-associated ALCL and nodal PTCL with T-follicular helper phenotype.

SUMMARY

Major advances in molecular and gene expression profiling has expanded our knowledge of these rare and aggressive diseases.

Hepatosplenic T-Cell Lymphoma in an Immunocompetent Male with Central Nervous System Invasion: A Rare Clinical Entity

Hepatosplenic T-cell lymphoma (HSTCL) is a very rare non-Hodgkin lymphoma with an aggressive clinical course and poor prognosis. Patients of this disease usually presented with hepatosplenomegaly, which can be misdiagnosed or delayed. Bone marrow (BM) and peripheral blood (PB) are frequently involved, however, central nervous system (CNS) involvement is less common. Here, we are reporting an unusual case of hepatosplenic γδ T-cell lymphoma in a 64-year-old man with CNS involvement. Flow cytometry immunophenotyping was proved of great diagnostic contribution. © 2018 International Clinical Cytometry Society.

Use of PEG-asparaginase in a case of Hepatosplenic γδ T-cell lymphoma with long-term remission after stem cell transplantation

Hepatosplenic γδ T-cell lymphoma (HSTCL) is a rare aggressive peripheral T-cell lymphoma. Prognosis is usually poor with a median survival between 8 and 16 months after traditional chemotherapy. Stem cell transplantation (SCT) is promising and with a more intense induction regimen, has yielded positive results. We report the use of pegylated-asparaginase (PEG-asparaginase) along with a conventional anthracycline-containing regimen in a 51-year-old male who was diagnosed with HSTCL, achieved a complete remission, and subsequently underwent peripheral blood SCT and remained in remission at the time of this case report.

Hepatosplenic T-Cell Lymphoma: A Rare Complication of Monotherapy with Thiopurines in Crohn's Disease

Hepatosplenic T-cell lymphoma (HSTCL) is an extremely rare and aggressive form of non-Hodgkin lymphoma associated with poor response to treatment and high mortality. There is an increased incidence among patients with inflammatory bowel disease, especially young male patients under 35 years old and on combination therapy (thiopurine and anti-TNF-α). We describe a case of HSTCL in a young male patient with stenosing ileal Crohn's disease on azathioprine monotherapy for 4.8 years admitted to our hospital with intra- abdominal sepsis. Despite chemotherapy, the patient eventually died 1 month after the diagnosis. Through a literature review, we identified 18 additional cases of HSTCL in Crohn's disease patients that had only been treated with thiopurine monotherapy. The authors intend to highlight the rarity of this diagnosis especially with azathioprine monotherapy and the diagnostic challenge in a case that presented with intra-abdominal sepsis.

Hepatosplenic γδ T Cell Lymphoma Involving the Brain

BACKGROUND

Brain involvement of hepatosplenic T cell lymphoma (HSTL) has not been reported so far.

CASE DESCRIPTION

We observed an extremely rare case of HSTL, which is a rare and aggressive variant of peripheral T cell lymphoma, generally showing predominant infiltration to the liver, spleen, and bone marrow and involving the brain. A 41-year-old Japanese woman presented with dysarthria and numbness of the right hand. Radiologic examination revealed a single 3-cm mass in the left frontal cortex, which was totally removed. Pathologic examination of the specimen demonstrated T cell lymphoma with a γδ cytotoxic T cell phenotype. Multiplex polymerase chain reaction analyses confirmed monoclonality of T cell receptor γ. Systemic examination revealed infiltration of atypical T lymphoid cells of the same phenotype in bone marrow and the presence of hepatosplenomegaly. We diagnosed HSTL involving the brain. The patient was treated with several courses of intensive chemotherapy, but it failed to achieve remission. She died of sepsis 4 months after the surgery.

CONCLUSIONS

HSTL can involve the brain. A diagnosis of HSTL involving the brain needs careful systemic evaluation. Timely and precise diagnosis that considers the systemic condition is important for appropriate treatment and better outcome.

Hepatic Lymphoma Diagnosis

Systemic hematopoietic disorders may present on liver biopsy, and rare cases of primary hepatic lymphoma (PHL) may be encountered. Hepatopathologists must be familiar with the full spectrum of hematopoietic disorders involving the liver and be prepared to exclude benign mimics. PHL, which is confined to the liver without extrahepatic involvement, can present as solitary or multiple nodules, raising consideration for carcinoma on imaging, or may mimic benign inflammatory conditions, posing a diagnostic challenge. This article describes clinical, morphologic, and immunophenotypic features of some of the most common hematopoietic neoplasms involving the liver, along with differential diagnosis and recommended ancillary testing.

Hepatosplenic T-cell Lymphoma: a review of clinicopathologic features, pathogenesis, and prognostic factors

Hepatosplenic T-cell lymphoma (HSTCL) is a rare and clinically aggressive type of T-cell lymphoma that arises most often in adolescents and young adults. Patients with HSTCL commonly present with B-symptoms and cytopenias, which may suggest a diagnosis of acute leukemia initially. Patients present with extranodal disease involving the spleen, liver and bone marrow; lymphadenopathy is usually absent. The lymphoma cells can show a spectrum of cell sizes and are of T-cell lineage, often negative for CD4 and CD8 and positive for T-cell receptor γδ or, less often, αβ. Recent studies have identified gene mutations in oncogenic pathways that are likely involved in pathogenesis and may be targets for therapy. Mutations in STAT3 or STAT5B lead to activation of the JAK/STAT pathway, and mutations involving SETD2, IN080 and ARID1 are involved in chromatin modification. Currently, there is no consensus standard of care for HSTCL patients, although several studies support a role for allogeneic hematopoietic stem cell transplant. Although patients with HSTCL are best treated in the context of clinical trials, the rarity of these neoplasms likely necessitates a multi-institutional approach. In this review, we focus on the clinicopathologic and genetic characteristics of HSTCL. We also discuss the differential diagnosis and therapeutic approaches.

Hepatosplenic Gamma Delta T-Cell Lymphoma (HSGDTCL): Two Rare Case Reports from Western India

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. Hepatosplenic T-cell lymphoma (HSGDTCL) is a rare entity, which is characterized by primary extra nodal disease with typical sinusoidal or sinusal infiltration of the liver and the spleen, respectively by expression of the T-cell receptor γδ chain, and by a number of other frequent clinicopathologic features, including aggressive course of disease. Secondary involvement of liver by hematopoietic malignancies is much more common as compared to primary liver involvement. Primary involvement of liver by non- Hodgkin's lymphoma (NHL) is documented and mostly DLBCL (diffuse large B cell lymphoma) type. But, T cell lymphoma primarily arising from liver is very rare. It occurred commonly in immunocompromised patients and prognosis is very poor. Here, we present two case reports of Hepatosplenic gamma-delta T-cell lymphoma (HSGDTCL) and both are immunocompetent patients. Liver biopsy from the mass and subsequent IHC (immunohistochemistry) were performed for the purpose of diagnosis, which were positive for LCA (leukocyte common antigen), CD2 and negative for CD5, CD20 and CD79a. First patient was a 63-year-old female with hepatitis C virus seropositivity presented with liver mass simulating hepatocellular carcinoma. Second patient was a 60-year- old male, chronic alcoholic patient, presented with liver mass and lytic bony lesion in pelvis. Both patients were managed with conventional CHOP (cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisolone) and showed complete response after 4 cycles of chemotherapy. After completion of 6 cycles of chemotherapy, both patients remained under 6-month surveillance period for any recurrence of the disease.

The aggressive peripheral T-cell lymphomas: 2017

BACKGROUND

T-cell lymphomas make up approximately 10%-15% of lymphoid malignancies. The frequency of these lymphomas varies geographically, with the highest incidence in parts of Asia.

DIAGNOSIS

The diagnosis of aggressive peripheral T-cell lymphoma (PTCL) is usually made using the World Health Organization classification. The ability of hematopathologists to reproducibly diagnose aggressive PTCL is lower than that for aggressive B-cell lymphomas, with a range of 72%-97% for the aggressive PTCLs. Risk Stratification: Patients with aggressive PTCL are staged using the Ann Arbor Classification. Although somewhat controversial, positron emission tomography scans seem to be useful as they are in aggressive B-cell lymphomas. The specific subtype of aggressive PTCL is an important risk factor with the best survival seen in anaplastic large-cell lymphoma-particularly young patients with the anaplastic lymphoma kinase positive subtype.

RISK-ADAPTED THERAPY

Anaplastic large-cell lymphoma is the only subgroup to have a good response to a CHOP-like regimen. Angioimmunoblastic T-cell lymphoma has a prolonged disease-free survival in only ∼20% of patients, but younger patients who have an autotransplant in remission seem to do better. PTCL-not otherwise specified is not one disease. Anthracycline-containing regimens have disappointing results, and a new approach is needed. Natural killer/T-cell lymphoma localized to the nose and nasal sinuses seems to be best treated with radiotherapy-containing regimens and the majority of patients are cured. Enteropathy-associated PTCL and hepatosplenic PTCL are rare disorders with a generally poor response to therapy although selected patients with enteropathy- associated PTCL seem to benefit from intensive therapy.

Gamma-delta (γδ) T-cell lymphoma - another case unclassifiable by World Health Organization classification: a case report

Background

We present a case of gamma-delta T-cell lymphoma that does not fit the current World Health Organization classifications.

Case presentation

A 74-year-old Caribbean-American woman presented with lymphocytosis, pruritus, and non-drenching night sweats. Bone marrow and peripheral blood analyses both confirmed the diagnosis of gamma-delta T-cell lymphoma. An axillary lymph node biopsy was negative for lymphoma. Clinically absent hepatosplenomegaly and skin lesions with biopsy-proven gamma-delta T-cell lymphoma suggest that she is unclassifiable within the current classification system.

Conclusions

We believe this is a case of not otherwise specified gamma-delta T-cell lymphoma. Accumulation of these rare not otherwise specified cases will be important for future classification which further defines the biology of this disease.

Autologous and Allogeneic Hematopoietic Cell Transplantation in Peripheral T/NK-cell Lymphomas: A Histology-Specific Review

Peripheral T-cell lymphoma and natural killer/T-cell lymphomas (PT/NKCL) make up a diverse subgroup of non-Hodgkin's lymphomas characterized by an aggressive clinical course. The use of hematopoietic stem cell transplantation (HSCT) in the treatment of PT/NKCL remains controversial because of the absence of randomized controlled trials. The best available data suggest that certain subtypes of PT/NKCL may benefit more from the application of HSCT than other subtypes and that this benefit results from their unique clinical characteristics and underlying biology. Ultimately, however, prospective randomized controlled trials are needed to clarify the optimal type and timing of HSCT in patients with PT/NKCL.

Special situations in inflammatory bowel disease: First Latin American consensus of the Pan American Crohn's and Colitis Organisation (PANCCO) (Second part)

This is the first Latin American Consensus of the Pan American Crohn's and Colitis Organisation (PANCCO) regarding special situations in patients with inflammatory bowel disease (IBD). The aim of this consensus is to raise awareness in the medical community in all Latin American countries with respect to pregnancy, vaccinations, infections, neoplasms, including colorectal cancer, and pediatric issues in patients with IBD.

Uncommon Variants of T-Cell Lymphomas

Peripheral T-cell lymphomas represent 10% to 15% of non-Hodgkin lymphomas and comprise more than 20 different entities. Treatment of very rare T-cell lymphomas can be challenging because there are no large or randomized studies to guide clinical decision making, and treatment paradigms are often based on small series or imperfect data. Although a strict algorithm cannot be written with certainty, through the literature that exists and clinical experience, themes and principles of approaches do emerge that when coupled with clinical judgment allow reasonable and logical decisions.

Distinguishing Between Hepatosplenic T-cell Lymphoma and γδ T-cell Large Granular Lymphocytic Leukemia: A Clinicopathologic, Immunophenotypic, and Molecular Analysis

Hepatosplenic T-cell lymphoma (HSTCL) is a rare, aggressive T-cell lymphoma that can be challenging to diagnose. In particular, distinguishing HSTCL from T-cell large granular lymphocytic (T-LGL) leukemia of γδ T-cell receptor (TCR) type is difficult without examination of a splenectomy specimen. In this study, we systematically assessed a series of HSTCL cases for findings reported in the literature as supporting or not supporting the diagnosis of HSTCL. We also compared HSTCL with a group of cases of T-LGL of γδ TCR type. Criteria assessed in this study included: B-symptoms, massive splenomegaly, lymphadenopathy, extranodal involvement, peripheral lymphocytosis, lymphoma cells that expand bone marrow sinuses, lymphocyte azurophilic granules, immunophenotype, evidence of infection by Epstein-Barr virus, human immunodeficiency virus, or human T-cell leukemia virus type 1, isochromosome 7q, trisomy 8, and TCR gene rearrangement status. On the basis of the data of this study, we conclude that massive splenomegaly, bone marrow sinusoidal expansion by lymphoma cells, and lymphocytes devoid of azurophilic granules were significantly more common in HSTCL patients than in γδ T-LGL patients (P<0.0001), and these features help support the diagnosis of HSTCL.