Hodgkin lymphoma as Richter transformation in chronic lymphocytic leukaemia: a retrospective analysis of world literature

Lymphocytic Lymphoma Transforming into Hodgkin Lymphoma in Sub-Saharan Africa: Case Report and Literature Review

The Hodgkin variant Richter syndrome (HvRS) is an infrequent complication occurring in 1% of lymphocytic lymphoma/chronic lymphocytic leukemia patients. We report a case of HvRS diagnosed in Sub-Saharan Africa. A 63-year-old patient was consulted for the investigation of an abdominal mass that had been evolving for 5 years prior to admission. His history revealed night sweats, 13% weight loss in 3 months and persistent pruritis. Examination revealed bilateral cervical axillary and inguinal macroadenopathies, painless abdominal distension, pruritic lesions and WHO 2 PS. The blood count showed anemia at 9.5 g/dL. Histology revealed a lymphomatous proliferation of diffuse architecture, nodular in places, with Hodgkin and Sternberg cells associated with small lymphocytes, histiocytes and eosinophilic polymorphs. Immunohistochemistry showed CD20, PAX5, BCL2, CD5, CD23 and MYC positivity; Ki67 at 10% and cyclin D1, BCL6 and CD10 negativity; CD30 positivity on Hodgkin and Sternberg cells that remained CD20 negative; difficulty interpreting CD15; EBV positivity (EBERs); and CD3 and CD5 positivity on reactive T cells. CD138 and kappa and lambda light chains were non-contributory. The extension work-up classified the patient as Ann Arbor stage III B with a Hasenclever score of 3/7. This case illustrates the difficulties in diagnosing HvRS in our countries, where the number of haematopathologists is insufficient and the technical facilities are limited.

A + AVD for Treatment of Hodgkin Lymphoma Variant of Richter's Transformation

Hodgkin lymphoma variant of Richter's transformation (HvRT) is a rare complication for patients with chronic lymphocytic leukemia (CLL), with an overall poor prognosis. We present the first known case series of patients with HvRT treated with the combination of brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine (A + AVD). In our series of 4 patients, two patients treated with A + AVD for HvRT had durable remissions of 40 and 42 months, while two patients had disease progression and ultimately died. Continued investigation into the optimal management for patients with HvRT is still needed.

Richter transformation - retrospective treatment outcomes analysis in Polish Adult Leukemia Study Group

Richter transformation (RT) is defined as developing an aggressive lymphoma in 2-10% of patients suffering from chronic lymphocytic leukemia (CLL). So far, no complex analysis of RT demographics and treatment outcomes has been performed in Poland. Thus, the retrospective analysis of 124 patients with RT from Polish hematology centers was designed. Ninety-nine patients with diffuse large B-cell lymphoma (DLBCL-RT) were identified. The median overall survival (OS) for DLBCL-RT was 17.3 months, while for Hodgkin lymphoma (HL-RT)-21.3 months. In multivariate analysis, the independent factors of worse OS for DLBCL-RT were: prior CLL therapy, ECOG stage ≥2, and elevated serum LDH activity. Patients who proceeded to hematopoietic stem cell transplantation (HSCT) achieved better results. The median OS in allogeneic HSCT recipients was not reached, while in autologous HSCT median OS was 51.3 months. In conclusion, our study represents the largest dataset of patients diagnosed with RT in Poland and confirms its dismal prognosis.

A case of Hodgkin lymphoma-type Richter syndrome presenting as small-intestinal perforation

Hodgkin lymphoma type of Richter syndrome (HL-type RS) is a rare disease that arises in patients with chronic lymphocytic leukemia (CLL). HL-type RS lesions can manifest in various sites and are often accompanied by related symptoms. This is the first case report to describe diagnosis of HL-type RS after emergency surgery for gastrointestinal perforation caused by the development of a HL-type RS lesion. A 47-year-old man diagnosed with CLL three years prior began treatment with ibrutinib due to worsening anemia and splenomegaly two months prior to the emergency department presentation. Although splenomegaly improved, lymphocytopenia, anemia, and a newly arising mesenteric lymphadenopathy continued to worsen. He presented to the emergency department with abdominal pain, and subsequent surgery revealed small intestinal perforation and mesenteric lymphadenopathy with HL-type RS confirmed by histopathological examination of the resected small intestine. He subsequently received brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine (A + AVD), which effectively managed the HL-type RS. If CLL clinical presentation deviates from the typical course, an early tissue biopsy should be considered to evaluate for HL-type RS. Given the adoption of the A + AVD regimen as the standard treatment for Hodgkin lymphoma, further research is needed to evaluate its efficacy in HL-type RS.

From genetics to therapy: Unraveling the complexities of Richter transformation in chronic lymphocytic leukemia

Richter transformation (RT) refers to the progression of chronic lymphocytic leukemia, the most prevalent leukemia among adults, into a highly aggressive lymphoproliferative disorder, primarily a diffuse large B-cell lymphoma. This is a severe complication that continues to be a therapeutic challenge and remains an unmet medical need. Over the last five years, significant advances have occurred in uncovering the biological processes leading to the RT, refining criteria for properly diagnose RT from other entities, and exploring new therapeutic options beyond the ineffective chemotherapy. This review summarizes current knowledge in RT, including recent advances in the understanding of the pathogenesis of RT, in the classification of RT, and in the development of novel therapeutic strategies for this grave complication.

Richter Transformation of Chronic Lymphocytic Leukemia-Are We Making Progress?

PURPOSE OF REVIEW

The treatment paradigm of chronic lymphocytic leukemia (CLL) has dramatically changed with the advent of novel targeted agents over the past decade. Richter transformation (RT), or the development of an aggressive lymphoma from a background of CLL, is a well-recognized complication of CLL and carries significantly poor clinical outcomes. Here, we provide an update on current diagnostics, prognostication, and contemporary treatment of RT.

RECENT FINDINGS

Several genetic, biologic, and laboratory markers have been proposed as candidate risk factors for the development of RT. Although a diagnosis of RT is typically suspected based on clinical and laboratory findings, tissue biopsy is essential for histopathologic confirmation of diagnosis. The standard of care for RT treatment at this time remains chemoimmunotherapy with the goal of proceeding to allogeneic stem cell transplantation in eligible patients. Several newer treatment modalities are being studied for use in the management of RT, including small molecules, immunotherapy, bispecific antibodies, and chimeric antigen receptor T-cell (CAR-T) therapy. The management of patients with RT remains a challenge. Ongoing trials show enormous promise for newer classes of therapy in RT, with the hope being that these agents can synergize, and perhaps supersede, the current standard of care in the near future.

Immunological Aspects of Richter Syndrome: From Immune Dysfunction to Immunotherapy

Richter Syndrome (RS) is defined as the development of an aggressive lymphoma in patients with a previous or simultaneous diagnosis of chronic lymphocytic leukemia (CLL). Two pathological variants of RS are recognized: diffuse large B-cell lymphoma (DLBCL)-type and Hodgkin lymphoma (HL)-type RS. Different molecular mechanisms may explain the pathogenesis of DLBCL-type RS, including genetic lesions, modifications of immune regulators, and B cell receptor (BCR) pathway hyperactivation. Limited data are available for HL-type RS, and its development has been reported to be similar to de novo HL. In this review, we focus on the immune-related pathogenesis and immune system dysfunction of RS, which are linked to BCR over-reactivity, altered function of the immune system due to the underlying CLL, and specific features of the RS tumor microenvironment. The standard of care of this disease consists in chemoimmunotherapy, eventually followed by stem cell transplantation, but limited possibilities are offered to chemo-resistant patients, who represent the majority of RS cases. In order to address this unmet clinical need, several immunotherapeutic approaches have been developed, namely T cell engagement obtained with bispecific antibodies, PD-1/PD-L1 immune checkpoint blockade by the use of monoclonal antibodies, selective drug delivery with antibody-drug conjugates, and targeting malignant cells with anti-CD19 chimeric antigen receptor-T cells.

In Vitro Diffuse Large B-Cell Lymphoma Cell Line Models as Tools to Investigate Novel Immunotherapeutic Strategies

Despite the high incidence of diffuse large B-cell lymphoma (DLBCL), its management constitutes an ongoing challenge. The most common DLBCL variants include activated B-cell (ABC) and germinal center B-cell-like (GCB) subtypes including DLBCL with MYC and BCL2/BCL6 rearrangements which vary among each other with sensitivity to standard rituximab (RTX)-based chemoimmunotherapy regimens and lead to distinct clinical outcomes. However, as first line therapies lead to resistance/relapse (r/r) in about half of treated patients, there is an unmet clinical need to identify novel therapeutic strategies tailored for these patients. In particular, immunotherapy constitutes an attractive option largely explored in preclinical and clinical studies. Patient-derived cell lines that model primary tumor are indispensable tools that facilitate preclinical research. The current review provides an overview of available DLBCL cell line models and their utility in designing novel immunotherapeutic strategies.

[Clonality relatedness and molecular characteristics of Richter transformation]

Objective: To investigate the clinical, genetic, and clonality related aspects of individuals with Richter transformation (RT) . Methods: From January 2019 to December 2021, 18 RT patients with diagnoses at the First Affiliated Hospital of Nanjing Medical University (Pukou CLL center) were retrospectively examined. The immunoglobin heavy variable (IGHV) gene usage and IGHV-D-J rearrangement pattern of diagnosed CLL/SLL and transformed diffuse large B-cell lymphoma (DLBCL) were compared to determine the clonality relatedness. To investigate the risk factors of RT, Clinical and laboratory data from patients with newly diagnosed CLL/SLL and transformed DLBCL were gathered. Results: The median age of RT was 56.5 (41-75) years old. 17 patients transformed to DLBCL and 1 transformed to Hodgkin lymphoma (HL) . Of 17 individuals who had DLBCL transformation, 15 had CLL/SLL-related clonality and 2 had unrelated clonality. Next-generation sequencing (NGS) analysis of 11 paired initially diagnosed treatment-naive CLL/SLL and RT DLBCL found that EGR2、TP53 and NOTCH1 were among the most frequently mutated genes both in treatment-naive CLL/SLL and in RT DLBCL. In several cases, specific mutations were gained or lost throughout RT, indicating clonal evolution. Among 10 patients before exposure to BTK inhibitors before RT, four patients acquired BTK mutation. The aforementioned mutations should be considered high-risk variables for transformation; in addition, TP53 and EGR2 mutations could be linked to a poor prognosis following RT in patients receiving a cocktail of new medicines. Conclusion: Most RT DLBCL patients in our center are clonality related (15/17, 88.2% ) and we recommend all qualified centers to evaluate clonality relatedness of RT DLBCL patients. There was some variability in the mutational landscape between DLBCL that had undergone a transformation and initially diagnosed, treatment-naive CLL/SLL. The underlying molecular mechanism of RT needs more research.

Hodgkin's variant of Richter transformation during ibrutinib therapy: A case report and review of the literature

Hodgkin's variant of Richter transformation is a rare complication of chronic lymphocytic leukemia and is associated with inferior outcomes compared to de novo Hodgkin lymphoma. Further data concerning prognosis and treatment of Hodgkin's variant of Richter transformation occurring in the setting of novel targeted therapies are needed.

Richter Syndrome: From Molecular Pathogenesis to Druggable Targets

Richter syndrome (RS) represents the occurrence of an aggressive lymphoma, most commonly diffuse large B-cell lymphoma (DLBCL), in patients with chronic lymphocytic leukemia (CLL). Most cases of RS originate from the direct transformation of CLL, whereas 20% are de novo DLBCL arising as secondary malignancies. Multiple molecular mechanisms contribute to RS pathogenesis. B-cell receptor (BCR) overreactivity to multiple autoantigens is due to frequent stereotyped BCR configuration. Genetic lesions of TP53, CDKN2A, NOTCH1 and c-MYC deregulate DNA damage response, tumor suppression, apoptosis, cell cycle and proliferation. Hyperactivation of Akt and NOTCH1 signaling also plays a role. Altered expression of PD-1/PD-L1 and of other immune checkpoints leads to RS resistance to cytotoxicity exerted by T-cells. The molecular features of RS provide vulnerabilities for therapy. Targeting BCR signaling with noncovalent BTK inhibitors shows encouraging results, as does the combination of BCL2 inhibitors with chemoimmunotherapy. The association of immune checkpoint inhibitors with BCL2 inhibitors and anti-CD20 monoclonal antibodies is explored in early phase clinical trials with promising results. The development of patient-derived xenograft mice models reveals new molecular targets for RS, exemplified by ROR1. Although RS still represents an unmet medical need, understanding its biology is opening new avenues for precision medicine therapy.

Hodgkin Lymphoma and Hairy Cell Leukemia Arising from Chronic Lymphocytic Leukemia: Case Reports and Literature Review

Richter’s syndrome represents the progression of chronic lymphocytic leukemia (CLL) to more aggressive diseases, most frequently diffuse large B-cell lymphoma, while Hodgkin’s lymphoma (HL) and hairy cell leukemia (HCL) are rarely described. The first case involved a 67-year-old man with a diagnosis of a high-risk stage-II CLL treated with rituximab and ibrutinib, developed a HL nodular sclerosis variant after three months of therapy for CLL. After achieving a complete remission for HL and ibrutinib cessation because of drug-related cardiotoxicity, the patient relapsed after five months off-therapy and died due to disease progression after two cycles of brentuximab-vedotin. The second case involved an 83-year-old female with a diagnosis of stage-IV CLL treated with rituximab plus bendamustine who developed a HCL eight years later. Pentostatin was unsuccessfully employed as upfront HCL therapy, and the patient was then switched to rituximab while in remission for CLL. In conclusion, Richter’s transformation risk rate might be higher in patients treated with novel targeted therapies, and multiparametric flow cytometry and lymph node biopsy at relapse could help in early identifying small clones. The treatment of predominant neoplasia is mandatory, and disease-specific drugs are administered; however, clinical efficacy might be lower in these patients.

Outcomes of Hodgkin variant Richter transformation in chronic lymphocytic leukaemia and small lymphocytic lymphoma in British Columbia

Hodgkin variant Richter transformation (HvRT) is a rare and challenging complication of chronic lymphocytic leukaemia (CLL) for which information on prognostic factors and treatment approaches remain limited. We analysed characteristics and survival outcomes of a population-based cohort of 32 patients with HvRT identified in British Columbia over a 40-year period. Median interval from CLL diagnosis to HvRT was 5.6 years (range, 0-33.6), with five cases diagnosed concurrently. Most patients (80%) had treatment for CLL prior to HvRT. Median age at HvRT was 71 years (range, 51-86) and the majority of patients had high-risk disease, including stage 3-4 in 87% and International Prognostic Score (IPS) ≥ 4 in 65%. Two-year progression-free (PFS) and overall survival (OS) from HvRT were 47% (95% CI: 29%-64%) and 57% (95% CI: 38%-72%), respectively. OS from HvRT was significantly worse in those with anaemia (p = 0.02), elevated lactate dehydrogenase (p = 0.04), high IPS (p = 0.04), and worse performance status (p = 0.001). For those treated with curative-intent ABVD/ABVD-like therapy, 2-year PFS and OS were 70% (95% CI: 45%-85%) and 74% (95% CI: 49%-89%), respectively. In this real-world population-based cohort, HvRT was associated with poor clinical outcomes overall; however, those able to tolerate curative-intent therapy had similar survival to older patients with de novo HL.

Aberrant Expression of Lymphoid Enhancer-Binding Factor 1 (LEF1) in Hodgkin Lymphoma

Lymphoid enhancer-binding factor 1 (LEF1) is a transcription factor involved in T-cell maturation and is usually absent in mature B-cells. Previous studies have shown aberrant LEF1 expression as a sensitive and specific marker in chronic lymphocytic leukemia/small lymphocytic lymphoma. Our primary aims were i) to analyze LEF1 expression in classic Hodgkin lymphomas (CHL) including de novo and Richter syndrome (RS), and to assess if LEF1 can be a surrogate marker to assess clonal relationship in RS, and ii) to compare LEF1 expression in CHL and Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL). We included 117 patients: 24 CHL-RS, 66 CHL-de novo and 27 NLPHL. There was no significant difference in LEF1 expression between CHL-RS and CHL-de novo (79.2% vs 87.9%, P = 0.299), or in type I and type II CHL-RS (75% vs 81.3%, P = 1.000). However, CHL showed a significantly higher LEF1 expression compared to NLPHL (85.6% vs 44.4%, P<0.0001). As the Wnt/β-catenin pathway directly regulates LEF1 expression in a β-catenin-dependent way, β-catenin expression was assessed in 76 cases and all were negative. Additionally, no association between EBV-positivity and LEF1-expression was detected. Overall, our findings show high LEF1 expression in CHL, regardless of RS or de novo, indicating LEF1 cannot be utilized as a surrogate marker to suggest clonal relationship in RS. Compared with CHL, LEF1 expression is significantly less common in NLPHL, further attesting that they are biologically distinct entities. The absent β-catenin expression suggests LEF1 expression is independent of Wnt/β-catenin signaling pathway in Hodgkin lymphomas.

Biology and Treatment of Richter Transformation

Richter transformation (RT), defined as the development of an aggressive lymphoma on a background of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), represents a clinical unmet need because of its dismal prognosis. An increasing body of knowledge in the field of RT is arising from the recent development of preclinical models depicting the biology underlying this aggressive disease. Consistently, new therapeutic strategies based on a genetic rationale are exploring actionable pathogenic pathways to improve the outcome of patients in this setting. In this review, we summarize the current understandings on RT biology and the available treatment options.

Chronic lymphocytic leukemia (CLL) with Reed-Sternberg-like cells vs Classic Hodgkin lymphoma transformation of CLL: does this distinction matter?

The distinction between chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) with isolated Hodgkin/Reed-Sternberg cells (CLL-HRS; background milieu with a paucity of inflammatory cells) and overt transformation to classic Hodgkin lymphoma (CLL-HL; mixed inflammatory background) is incompletely understood. This retrospective study examined the clinicopathologic features of CLL-HRS (n = 15) and CLL-HL (n = 31) patients seen over the past three decades from a single institution. The phenotypic features of Reed-Sternberg cells in both groups were similar, including expression of CD30, CD15, and PAX5, as well as EBV status. However, a spectrum of background CLL/SLL infiltration amongst the HRS cells was noted on pathologic review, and four patients had both diagnoses, either concurrently or in succession. The median overall survival (OS) of patients with CLL-HRS was 17.5 months compared to 33.5 months for patients with CLL-HL (P = 0.24). Among patients with CLL-HRS, those who received Hodgkin-directed therapy had a significantly longer median OS (57 months) compared to those who received CLL-directed therapy (8.4 months, P = 0.02). Our clinical and pathologic findings suggest a biologic continuum between CLL-HRS and CLL-HL and indicate that CLL-HRS patients may benefit from Hodgkin-directed therapy.

First case of chronic cell leukemia discovered incidentally in extra-saccular inguinal lymph node during laparoscopic bilateral inguinal hernia repair. Case report and literature review

Introduction

Chronic cell leukemia discovered incidentally in extra-saccular inguinal lymph node during laparoscopic bilateral inguinal hernia repair is extremely rare.

Presentation of case

62-year-old Romanian male presented at the outpatient general surgery clinic in April 2019 complaining of bilateral inguinal swelling that gradually increased in size mainly on right side and was diagnosed with bilateral inguinal hernia. During the laparoscopic repair of the hernia, a large lymph node in the left femoral canal was incidentally observed. Histopathologic, immunohistochemical, and flowcytometric evaluation of the excised specimen confirmed chronic lymphocytic leukemia/small lymphocytic lymphoma.

Discussion

Whole body CT showed supra and infra-diaphragmatic lymphadenopathy, and few small subsolid pulmonary nodules, possibly metastatic. Splenomegaly and pancreatomegaly were also noted, suggesting lymphomatoid infiltration.

Conclusion

There is need for cautious inspection and meticulous palpation of the inguinal area for any lymphadenopathy during routine inguinal hernia repair.

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Chronic lymphocytic leukemia (CLL) is a B-cell lymphoid neoplasm.

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CLL diagnosed incidentally in extra-saccular inguinal lymph node during inguinal hernia repair is extremely rare.

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Surgeons need inspection and meticulous palpation of inguinal area for any lymphadenopathy during inguinal hernia repair.

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No advantage of early initiation of treatment on early stages of chronic lymphocytic leukemia

Hodgkin lymphoma arising in patients with chronic lymphocytic leukemia: outcomes from a large multi-center collaboration

Chronic lymphocytic leukemia (CLL) patients who develop Hodgkin lymphoma (HL) have limited survival. No current therapeutic standard of care exists. We conducted a multi-center retrospective study of patients with Hodgkin Transformation (HT) of CLL. Clinicobiologic characteristics, treatment type, and survival outcomes were analyzed and compared with historic case series. Ninety-four patients were identified. Median age at HT was 67 years (range, 38-85). Median time from CLL diagnosis to HT was 5.5 years (range, 0-20.2). Prior to HT, patients received a median of 2 therapies for CLL (range, 0-12). As initial therapy for HT, 61% (n=62) received ABVD-based regimens (adriamycin, bleomycin, vinblastine, and dacarbazine). Seven (7%) patients received hematopoietic cell transplantation (HCT) while in first complete remission (CR1). The median number of treatments for HT per patient was 1 (range, 0-5) with 59 (61%) patients only receiving one line of therapy. After HT, patients had a median follow-up of 1.6 years (range, 0-15.1). Two-year overall survival (OS) after HT diagnosis was 72% (95%CI 62-83%). The patients who received standard ABVD-based therapy had a median OS of 13.2 years. Although limited by small sample size, the patients who underwent HCT for HT in CR1 had a similar 2-year OS (n=7; 67%) compared to patients who did not undergo HCT for HT in CR1 (n=87; 72%; p=0.46). In this multi-center study, HT patients treated with ABVD-based regimens had prolonged survival supporting the use of these regimens as standard of care for these patients.

Unique case of atraumatic splenic rupture in a patient with chronic lymphocytic leukaemia with Richter's transformation

Though rare, atraumatic rupture of the spleen can be a complication in certain leukaemias and lymphomas. We present a unique case of atraumatic rupture of the spleen in a patient with chronic lymphocytic leukaemia. The patient presented to the emergency department with abdominal pain; he had been on ibrutinib therapy but stopped taking the medication abruptly 6 days prior. On evaluation, he was found to have a ruptured spleen with a haemoperitoneum. Pathology of the excised spleen showed infiltration of the spleen with hyperproliferated CD5+ intermediate-to-large cells, consistent with B-cell lymphoma and favouring Richter's transformation. There are only a few available reports of patients with similar presentations identified in our literature review.

Early Transformation to Classic Hodgkin Lymphoma in a Chemotherapy-naïve Chronic Lymphocytic Leukemia Patient upon Initial Treatment with Ibrutinib

A 71-year-old woman with a four-year history of chronic lymphocytic leukemia (CLL) received ibrutinib as initial treatment due to progressive anemia and thrombocytopenia. Eleven months after the start of the treatments, although her cytopenia had ameliorated, she developed classic Hodgkin lymphoma, a rare form of Richter's transformation. She was successfully treated with two courses of adriamycin, vinblastin, bleomycin and dacarbazine followed by radiotherapy. In general, several clinical, genetic and molecular factors are associated with Richter's transformation. In addition, our present case suggested that ibrutinib could be a potential risk factor for Richter's transformation in CLL patients.

Hodgkin Variant of Richter's Transformation in Chronic Lymphocytic Leukemia (CLL): An Illustrative Case Report and Literature Review

Hodgkin lymphoma variant of Richter's transformation (HL-RT) is a rare event, occurring in < 1% chronic lymphocytic leukemia (CLL) cases, of which, in < 10% cases, HL is the first finding leading to a diagnosis of CLL that co-exists simultaneously. Here we report a 60 years old male patient who presented with an outside diagnosis of lymphocyte-rich classical HL. On evaluation, he had only B-symptoms in the form of low-grade fever and weight loss. Peripheral smear revealed mild leukocytosis with an absolute lymphocytosis and a few smudge cells. Bone marrow (BM) aspirate and biopsy exhibited diffuse infiltration by a small cell, low grade, Non-Hodgkin's lymphoma with no immunohistochemical evidence of HL. Flow cytometry performed on BM was consistent with classical immunoprofile of CLL. Meanwhile the lymph node received for review revealed diffuse effacement of nodal architecture by small mature lymphocytes with immunoprofile of CLL expressing CD20, CD5, and CD23. Interspersed between these cells, were a few eosinophils along with classical Reed Sternberg cells, expressing CD30, MUM-1, CD15, and dim PAX-5, with a surrounding rosette of T-Cells highlighted by CD3 and PD-1 and negative for CD45, CD20, and EBV immunohistochemistry. Fluorodeoxyglucose positron emission tomography (FDG-PET) scan revealed hepatosplenomegaly with multiple supra/infra diaphragmatic lymph nodes. So, a final diagnosis of HL-RT in CLL was considered. The patient is currently doing well after the first cycle of ABVD chemotherapy. HL-RT occurring in CLL is a rare event with heterogeneous clinical presentation, morphology, clonal origin, disease course, prognostic features, and survival.

Reduced-intensity conditioning hematopoietic stem cell transplantation for chronic lymphocytic leukemia and Richter's transformation

Allogeneic hematopoietic stem cell transplantation (HSCT) may potentially cure patients with chronic lymphocytic leukemia (CLL) and Richter's transformation (CLL-RT) or CLL without RT, but the impact of novel agents on HSCT is unclear. CLL-RT patients have a grave prognosis, and their outcomes after HSCT are uncertain. We conducted a retrospective analysis of all 58 CLL patients, including 23 CLL-RT patients, who underwent reduced intensity conditioning (RIC) HSCT at Memorial Sloan Kettering Cancer Center (New York, NY) between September 2006 and April 2017. With a median follow-up of 68 months (range, 24-147 months), 5-year progression-free survival (PFS) was 40% (95% confidence interval [CI], 28%-56%), and overall survival (OS) was 58% (95% CI, 48%-74%). The 1-year graft-versus-host disease/relapse-free survival (GRFS) was 38% (95% CI, 25%-50%). Patients with CLL-RT and CLL patients without RT had comparable outcomes. In both cohorts, treatment-sensitive response and ≤3 previous lines of therapy produced superior PFS and OS. Outcomes were agnostic to adverse cytogenetic and molecular features. Novel agents did not have a negative impact on HSCT outcomes. Total body irradiation (TBI)-containing RIC yielded inferior PFS, OS, and GRFS. CLL-RT patients older than age 55 years who had an HSCT Comorbidity Index score of ≥2 demonstrated inferior OS. This study, which is the largest series of RIC-HSCT for patients with CLL-RT, provides evidence supporting RIC-HSCT in early remission courses for patients with CLL-RT and poor-risk CLL patients. TBI-containing RIC should be considered with caution.

Morphologic and molecular analysis of Richter syndrome in chronic lymphocytic leukaemia patients treated with ibrutinib or venetoclax

Richter syndrome (RS) represents the development of high-grade lymphoma in patients with chronic lymphocytic leukaemia (CLL) or small lymphocytic lymphoma (SLL) and presents a diagnostic and therapeutic challenge with an adverse prognosis. The genetic background and morphology of RS in CLL patients treated with chemoimmunotherapy is extensively characterised; however, our knowledge about RS in patients treated with targeted oral therapies should be extended. To understand the morphologic and molecular changes leading to RS in CLL patients treated with the Bruton's tyrosine kinase inhibitor, ibrutinib, and the BCL2 inhibitor, venetoclax, sequential samples from six CLL/SLL patients undergoing RS were collected in both the CLL and RS phases. A detailed immunophenotypic analysis of formalin-fixed, paraffin-embedded tissue specimens of RS phase was performed, followed by extensive molecular characterisation of CLL and RS samples, including the immunoglobulin heavy chain gene (IGH) rearrangement, TP53 mutations, drug-induced resistance mutations in BTK and BCL2 genes and various copy number changes and point mutations detectable with multiplex ligation-dependent probe amplification (MLPA). Rare, non-diffuse large B-cell lymphoma phenotypes of RS were observed in 3/6 cases, including plasmablastic lymphoma and a transitory entity between diffuse large B-cell lymphoma and classical Hodgkin lymphoma. The majority of cases were clonally related and harboured an unmutated variable region of the immunoglobulin heavy chain gene. Abnormalities affecting the TP53 gene occurred in all patients, and every patient carried at least one genetic abnormality conferring susceptibility to RS. In the background of RS, 2/5 patients treated with ibrutinib showed a BTK C481S resistance mutation. One patient developed a BCL2 G101V mutation leading to venetoclax resistance and RS. In conclusion, our findings contribute to better understanding of RS pathogenesis in the era of targeted oral therapies. Rare phenotypic variants of RS do occur under the treatment of ibrutinib or venetoclax, and genetic factors leading to RS are similar to those identified in patients treated with chemoimmunotherapy. To our best knowledge, we have reported the first BCL2 G101V mutation in an RS patient treated with venetoclax.

Revisiting Richter transformation in the era of novel CLL agents

Richter transformation (RT) is the development of aggressive lymphoma - most frequently diffuse large B-cell lymphoma (DLBCL) and rarely Hodgkin lymphoma (HL) - arising on the background of chronic lymphocytic leukaemia (CLL). Despite recent advances in CLL treatment, RT also develops in patients on novel agents, usually occurring as an early event. RT incidence is lower in CLL patients treated with novel agents in the front line compared to relapsed/refractory cases, with a higher incidence in patients with TP53 disruption. The genetic heterogeneity and complexity are higher in RT-DLBCL than CLL; the genetics of RT-HL are largely unknown. In addition to TP53, aberrations in CDKN2A, MYC, and NOTCH1 are common in RT-DLBCL; however, no distinct RT-specific genetic aberration is recognised yet. RT-DLBCL on ibrutinib is frequently associated with BTK and PLCG2 mutations. Here, we update on genetic analysis, diagnostics and treatment options in RT in the era of novel agents.

Richter Syndrome

PURPOSE OF REVIEW

Richter syndrome (RS) is an uncommon but aggressive evolution of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). RS is an unmet clinical need in the field of CLL. Recent advances in understanding the biology of this condition provide the rationale for testing new therapeutic concepts in order to improve the outcome of patients developing RS, which is so far poor. In this review, we summarize disease characteristics and available therapeutic options for RS.

RECENT FINDINGS

Current regimens with novel agents in monotherapy have shown little impact on survival. Nevertheless, the better reported outcome for RS has been achieved with the combination of chemo-immunotherapy with a novel agent, confirming the synergistic effect of the approaches. Still, the frailty of this population may impose a less toxic management leaving most patients with no reasonable therapeutic option. Treatment options for RS need to be further expanded. Preclinical models in current development may allow to explore actionable pathways and identify new drug targeted combinations.

Hodgkin Reed-Sternberg-Like Cells in Non-Hodgkin Lymphoma

Reed-Sternberg cells (RSCs) are hallmarks of classic Hodgkin lymphoma (cHL). However, cells with a similar morphology and immunophenotype, so-called Reed-Sternberg-like cells (RSLCs), are occasionally seen in both B cell and T cell non-Hodgkin Lymphomas (NHLs). In NHLs, RSLCs are usually present as scattered elements or in small clusters, and the typical background microenviroment of cHL is usually absent. Nevertheless, in NHLs, the phenotype of RSLCs is very similar to typical RSCs, staining positive for CD30 and EBV, and often for B cell lineage markers, and negative for CD45/LCA. Due to different therapeutic approaches and prognostication, it is mandatory to distinguish between cHL and NHLs. Herein, NHL types in which RSLCs can be detected along with clinicopathological correlation are described. Moreover, the main helpful clues in the differential diagnosis with cHL are summarized.

Cytomegalovirus and Epstein-Barr Infections: Prevalence and Impact on Patients with Hematological Diseases

Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections are widely distributed throughout the world. EBV is linked to various hematological and autoimmune disorders whereas CMV might play important role in the progression of chronic hematological diseases, such as hemoglobinopathies, lymphomas, myelomas, hemophilia, and aplastic and sickle cell anemia. Both viruses produce a viral homolog of human interleukin-10 that can cause general suppression of immune response, increasing susceptibility to other infections. These viruses can remain latent in the host cells and be reactivated when the host immune system is compromised. Studies showing the impact of CMV and EBV infections on hematological disorders are scarce and unclear in the context of coinfection. This review intends to present the biology, prevalence, and impact of CMV and EBV infections in patients with hematological diseases.

Complexities in the diagnosis of large B-cell lymphomas, classic Hodgkin lymphomas and overlapping peripheral T-cell lymphomas simplified: An evidence-based guide

The diagnosis of a large B-cell lymphoma and classic Hodgkin lymphoma (CHL) is often straightforward. However, in select circumstances, these simple diagnoses can be quite complex. In part, diagnostic difficulty may be due to uncertainty in the evaluation of morphologic and immunophenotypic features along a biologic continuum, or alternatively arise from uncertainty in predicting the behavior and outcomes of patients. Here, we systematically discuss and review areas of diagnostic difficulty in the diagnosis of large B-cell lymphomas (LBCL), classic Hodgkin lymphomas (CHL) and peripheral T-cell lymphomas (PTCL). We provide careful data-driven analyses and evidence-based approaches to help guide pathologists and clinicians. We discuss: 1) marginal zone lymphomas with increased large cells versus diffuse large B-cell lymphoma (DLBCL), 2) chronic lymphocytic leukemia with expanded proliferation centers versus diffuse large B-cell lymphoma (DLBCL), 3) chronic lymphocytic leukemia with Hodgkin/Reed-Sternberg-like cells versus CHL arising from chronic lymphocytic leukemia, 4) complex cases of follicular lymphoma versus DLBCL, 5) PTCL with large B-cell proliferations versus PTCL with LBCL, 6) PTCL with Hodgkin/Reed-Sternberg-like cells versus CHL, and finally 7) blastoid/pleomorphic mantle cell lymphoma versus DLBCL. Our evidence and data driven approach may serve as a useful diagnostic guide.

Richter transformation in chronic lymphocytic leukemia (CLL)-a pooled analysis of German CLL Study Group (GCLLSG) front line treatment trials

Richter transformation (RT) is defined as development of aggressive lymphoma in patients (pts) with CLL. The incidence rates of RT among pts with CLL range from 2 to 10%. The aim of this analysis is to report the frequency, characteristics and outcomes of pts with RT enrolled in trials of the GCLLSG. A total of 2975 pts with advanced CLL were reviewed for incidence of RT. Clinical, laboratory, and genetic data were pooled. Time-to-event data, starting from time of CLL diagnosis, of first-line therapy or of RT diagnosis, were analyzed by Kaplan-Meier methodology. One hundred and three pts developed RT (3%): 95 pts diffuse large B-cell lymphoma (92%) and eight pts Hodgkin lymphoma (8%). Median observation time was 53 months (interquartile range 38.1-69.5). Median OS from initial CLL diagnosis for pts without RT was 167 months vs 71 months for pts with RT (HR 2.64, CI 2.09-3.33). Median OS after diagnosis of RT was 9 months. Forty-seven pts (46%) received CHOP-like regimens for RT treatment. Three pts subsequently underwent allogeneic and two pts autologous stem cell transplantation. Our findings show that within a large cohort of GCLLSG trial participants, 3% of the pts developed RT after receiving first-line chemo- or chemoimmunotherapy. This dataset confirms the ongoing poor prognosis and high mortality associated with RT.

Combined Tumors in Hematolymphoid Neoplasms: Case Series of Histiocytic and Langerhans Cell Sarcomas Arising From Low-Grade B-Cell Lymphoma

We report an index case of histiocytic sarcoma arising in a 70-year-old patient with long-standing chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). The patient presented in 2017 with painful, enlarging swelling of the left neck. He had remote history of cutaneous squamous cell carcinoma with no sign of recurrence, and his CLL/SLL was thought to be in remission. Computed tomography showed mild splenomegaly and multifocal lymphadenopathy including a 3-cm left neck mass. Biopsy of the left neck mass showed CLL/SLL with associated histiocytic sarcoma. Flow cytometry demonstrated a B cell neoplasm with CLL/SLL phenotype. Despite radiation therapy, he expired 3 months after presentation. Two similar cases (CLL/SLL and histiocytic sarcoma, follicular lymphoma and Langerhans cell sarcoma) from another institution are also illustrated. The pathological features of combined tumors in lymphoid neoplasms, a general framework to the work-up to determine interrelatedness of tumor components, and the clinical relevance are discussed.

Rapid and complete response to idelalisib in a case of Richter syndrome

Richter syndrome (RS) is an aggressive lymphoma arising on the back of chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) and is the most common B-cell malignancy in the Western world. In the majority of cases, RS presents an activated B cell (ABC) phenotype of diffuse large B-cell lymphoma (DLBCL). From the therapeutic point of view, selective inhibition of PI3Kδ with idelalisib represents a valuable addition to available treatment options for patients with CLL/SLL, many of whom do not respond to or cannot tolerate chemoimmunotherapy. However, to our knowledge, there have been no prospective studies evaluating idelalisib efficacy in a DLBCL-ABC form of RS. Here, we present a case of a DLBCL-ABC form of RS achieving a complete response at 3 weeks after initiating idelalisib and rituximab therapy for six cycles. This response was maintained during the idelalisib monotherapy, but the patient relapsed rapidly after treatment was withdrawn, because of a grade three immune colitis that developed at 10 months of treatment. This report demonstrates that idelalisib is highly effective in RS and provides an attractive option in this aggressive disease. This agent could meet an unmet need by providing a treatment option with a tolerable safety profile for elderly patients with RS.

Immunochemotherapy for Richter syndrome: current insights

Richter syndrome (RS) is recognized as the development of a secondary and aggressive lymphoma during the clinical course of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Most of such histological transformations are from RS to diffuse large B-cell lymphoma (DLBCL-RS, 90%) and Hodgkin’s lymphoma (HL-RS, 10%). Histopathological examination is a prerequisite for diagnosis. It is crucial to assess the relationship between the RS clone and the underlying CLL/SLL because clonally related DLBCL-RS has a poor outcome, while clonally unrelated cases have a prognosis similar to de novo DLBCL. An anti-CD20 antibody-based immunochemotherapy is hitherto the frontline treatment of choice for DLBCL-RS; nonetheless, the results are unsatisfactory. Allogeneic stem cell transplantation should be offered to younger and fit patients as a consolidative treatment; however, the majority of the patients may not be qualified for this procedure. The HL-RS transformation has better outcomes than those of DLBCL-RS and can effectively be treated by the adriamycin, bleomycin, vinblastine, and dacarbazine regimen. Although novel agents are currently being investigated for RS, immunochemotherapy nevertheless remains a standard treatment for DLBCL-RS.

Current trends in the management of Richter's syndrome

Richter's syndrome (RS) is a life-threatening complication of chronic lymphocytic leukemia (CLL). While previous research has increased our knowledge on the distinct evolutionary patterns of RS and provided a deeper understanding of the risk factors and molecular events predisposing to transformation, there remain few targetable aberrations and treatment is largely ineffective. The ability to obtain deeper remissions, without selecting for deletion 17p, by using novel B-cell receptor (BCR) antagonists and bcl2 inhibition might lead to a decrease in the incidence of RS, but these agents have done little to significantly change outcomes when incorporated into treatment regimens for RS. In this review we highlight the current landscape of molecular lesions specific to RS, review the data on historical treatment options, and look to the horizon for potential opportunities in the future.

Richter transformation in the era of novel agents

Recent approvals of several oral targeted agents have revolutionized chronic lymphocytic leukemia (CLL) therapy. However, CLL patients continue to progress; particularly, 4% to 20% of previously treated CLL patients undergo transformation into high-grade lymphoma. Richter transformation is defined as a transformation of CLL into aggressive lymphoma, most commonly diffuse large B-cell lymphoma. These patients typically have poor response to traditional chemotherapy used to treat de novo diffuse large B-cell lymphoma and similar or shorter overall survival (median 3-11 months) in the era of novel agents. Here, I review the contemporary literature on Richter transformation, particularly in the context of novel agents used in CLL, and discuss the management approach for these patients.

Classic Hodgkin Lymphoproliferative Diseases Clonally Unrelated to B-Chronic Lymphocytic Leukemia Successfully Treated with Bendamustine Plus Rituximab

A 62-year-old male was diagnosed with chronic lymphocytic leukemia (CLL) and treated with a fludarabine-containing regimen which maintained the disease in a partial response. Nine years after diagnosis, a rapidly growing systemic lymphadenopathy was observed, and a biopsy specimen revealed the presence of typical Hodgkin/Reed-Sternberg (HRS) cells, surrounded by T-lymphocytes and CLL cells. Sequencing analysis of the germline complementary determining region 3 (CDR3) region of the immunoglobulin heavy chain (IGH) gene showed that the Hodgkin/Reed-Sternberg cells were clonally unrelated to the preexisting CLL cells and the HRS cells were composed of five different clones, leading to the molecular diagnosis of de novo lymphocyte-rich classic Hodgkin lymphoproliferative diseases (LPDs) with small lymphocytic lymphoma (SLL). As the initial treatment was neither effective for classic Hodgkin LPDs nor for SLL, Bendamustine, Rituximab (BR) was started and complete remission was achieved, which has continued for more than one year so far. BR may be a good therapeutic option for both entities without causing hematological toxicity.

Biology and treatment of Richter syndrome

Richter syndrome (RS) is the development of an aggressive lymphoma in patients with chronic lymphocytic leukemia (CLL). Two pathologic variants of RS are recognized: namely, the diffuse large B-cell lymphoma (DLBCL) variant and the rare Hodgkin lymphoma (HL) variant. Histologic documentation is mandatory to diagnose RS. The clinical suspicion of RS should be based on clinical signs and symptoms. Differential diagnosis between CLL progression and RS and choice of the biopsy site may take advantage of positron emission tomography/computed tomography. Molecular lesions of regulators of proliferation (CDKN2A, NOTCH1, MYC) and apoptosis (TP53) overall associate with ∼90% of DLBCL-type RS, whereas the biology of the HL-type RS is largely unknown. The prognosis of the DLBCL-type RS is unfavorable; the outcome of HL-type RS appears to be better. The most important RS prognostic factor is the clonal relationship between the CLL and the aggressive lymphoma clones, with clonally unrelated RS having a better prognosis. Rituximab-containing combination chemotherapy for DLBCL is the most widely used treatment in DLBCL-type RS. Fit patients who respond to induction therapy should be offered stem cell transplantation (SCT) to prolong survival. Adriamycin, bleomycin, vinblastine, and dacarbazine is the preferred regimen for the HL-type RS, and SCT consolidation is less used in this condition.

Richter transformation driven by Epstein-Barr virus reactivation during therapy-related immunosuppression in chronic lymphocytic leukaemia

The increased risk of Richter transformation (RT) in patients with chronic lymphocytic leukaemia (CLL) due to Epstein-Barr virus (EBV) reactivation during immunosuppressive therapy with fludarabine other targeted agents remains controversial. Among 31 RT cases classified as diffuse large B-cell lymphoma (DLBCL), seven (23%) showed EBV expression. In contrast to EBV^- tumours, EBV⁺ DLBCLs derived predominantly from IGVH-hypermutated CLL, and they also showed CLL-unrelated IGVH sequences more frequently. Intriguingly, despite having different cellular origins, clonally related and unrelated EBV⁺ DLBCLs shared a previous history of immunosuppressive chemo-immunotherapy, a non-germinal centre DLBCL phenotype, EBV latency programme type II or III, and very short survival. These data suggested that EBV reactivation during therapy-related immunosuppression can transform either CLL cells or non-tumoural B lymphocytes into EBV⁺ DLBCL. To investigate this hypothesis, xenogeneic transplantation of blood cells from 31 patients with CLL and monoclonal B-cell lymphocytosis (MBL) was performed in Rag2^-/- IL2γc^-/- mice. Remarkably, the recipients' impaired immunosurveillance favoured the spontaneous outgrowth of EBV⁺ B-cell clones from 95% of CLL and 64% of MBL patients samples, but not from healthy donors. Eventually, these cells generated monoclonal tumours (mostly CLL-unrelated but also CLL-related), recapitulating the principal features of EBV⁺ DLBCL in patients. Accordingly, clonally related and unrelated EBV⁺ DLBCL xenografts showed indistinguishable cellular, virological and molecular features, and synergistically responded to combined inhibition of EBV replication with ganciclovir and B-cell receptor signalling with ibrutinib in vivo. Our study underscores the risk of RT driven by EBV in CLL patients receiving immunosuppressive therapies, and provides the scientific rationale for testing ganciclovir and ibrutinib in EBV⁺ DLBCL. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Plasmablastic Lymphoma with Coexistence of Chronic Lymphocytic Leukemia in an Immunocompetent Patient: A Case Report and Mini-Review

Background

Plasmablastic lymphoma (PBL) is a rare, aggressive B-cell lymphoma with poor prognosis usually found in the oral cavity of HIV-positive patients. Chronic lymphocytic leukemia (CLL) is an indolent B-cell lymphoma with a variable clinical course. Transformation of CLL to PBL as Richter's syndrome is rare while coexistence of CLL and PBL at diagnosis is even rarer.

Case Report

We describe a case of a male immunocompetent patient with an ileum-cecum valve mass and a soft tissue mass at the left humerus with histologic evidence of PBL with coexistence of CLL in the bone marrow and peripheral blood. Amputation of the patient's left arm was inevitable, and the patient was started on bortezomib and dexamethasone. However, prolonged hospitalization was complicated by aspiration pneumonia, and the patient passed away.

Conclusions

No standard of care exists for patients with PBL, and prognosis remains dismal. Concomitant presentation of hematological malignancies becomes increasingly recognized, and further insight is needed in order to delineate whether they originate from the same clone or from different ones.

Second lung malignancy and Richter syndrome in chronic lymphocytic leukemia: case report and literature review

BACKGROUND

Chronic lymphocytic leukemia (CLL) is the most frequent lymphoproliferative disease. Transformation into Richter disease and occurrence of second malignancies involving the lungs are rare complications. The hallmarks of any thoracic involvement are still unknown.

CASE PRESENTATION

We report a case of a 56-year-old male patient, with history of tobacco smoking, who presented with recurrent hemoptysis, fatigue and weight loss. Physical examination was normal except a slightly enlarged supraclavicular lymph node. Chest x-ray revealed a mediastinal widening due to enlarged paratracheal nodes and a left parahilar infiltrate. Blood tests showed a hyperlymphocytosis and a biological inflammatory syndrome. CT scan showed bilateral mediastinal and axillary lymphadenopathy, as well as left supraclavicular lymphadenopathy, with a left upper lobe alveolar attenuation and a solitary contralateral pulmonary nodule. Examination of Virchow's node and bone marrow biopsies confirmed metastasis of a pulmonary adenocarcinoma, as well as chronic lymphocytic leukemia with Richter's transformation. The clinical course was unfavorable since the first days of therapy as the patient passed away in a matter of a few days.

CONCLUSIONS

Steady surveillance of CLL patients and systematic screening for second solid tumors, particularly lung cancer, and Richter's transformation seem to be relevant more than ever. Early diagnosis might help us understand the pathways leading to these complications and adapt therapy.

Richter Transformation: An Unexpected Diffuse Large B-Cell Lymphoma Within a Fatty Mesenteric Mass in a Patient With Refractory Chronic Lymphocytic Leukemia

Richter transformation is the development of a high-grade lymphoma from chronic lymphocytic leukemia. This rare disease manifestation is difficult to predict and carries a poor prognosis. We describe the case of a 75-year-old man with refractory chronic lymphocytic leukemia who presented with multiple growing fatty abdominal masses on computed tomography and vague abdominal distension. The patient underwent exploratory laparotomy with mass resection due to the nonspecific imaging findings. A mesenteric mass was found to contain nodules of diffuse large B-cell lymphoma. This case highlights the importance of radiologists to consider the prospect tumor transformation in the differential diagnosis of enlarging abdominal masses.