Favorable outcome of primary mediastinal large B-cell lymphoma in a single institution: the British Columbia experience

Isolated central nervous system relapse in two adolescents with primary mediastinal large B-cell lymphoma after treatment with R-DA-EPOCH

The addition of rituximab to standard regimens for primary mediastinal large B-cell lymphoma (PMBCL) has significantly improved overall survival. However, the optimal management of isolated central nervous system (CNS) relapse and role of CNS prophylaxis remains undefined. We present cases of two adolescents with PMBCL who developed isolated CNS relapses. While isolated CNS relapse may be managed with high-dose chemotherapy and autologous stem cell transplant with or without CNS radiotherapy, review of these cases and the literature highlight the need for further work to define risk factors for CNS relapse, and identify patients who may benefit from CNS prophylaxis.

Diffuse large B-cell lymphoma presenting with pulmonary artery compression symptoms, case reports

Mediastinal diffuse large B-cell lymphoma (DLBC) may manifest in different presentations including systemic symptoms and local mass symptoms. We report two cases of diffuse large B-cell lymphoma presenting with pulmonary artery compression symptoms. The first case is of a 38-year-old Asian man which mimicked pulmonary embolism, and the second one is of a 27-year-old Asian woman who presented with fainting and respiratory symptoms due to local mass effect. Both cases were significantly improved after treatment. Local mass effect symptoms may be the first clinical presentation in DLBC lymphoma and should not be overlooked.

Improved survival for dose-intensive chemotherapy in primary mediastinal B-cell lymphoma: a systematic review and meta-analysis of 4,068 patients

Primary mediastinal B-cell lymphoma (PMBCL) is a distinct clinicopathologic entity. Currently, there is a paucity of randomized prospective data to inform on optimal front-line chemoimmunotherapy (CIT) and use of consolidative mediastinal radiation (RT). To assess if distinct CIT approaches are associated with disparate survival outcomes, we performed a systematic review and meta-analysis comparing dose-intensive (DI-CIT) versus standard CIT for the front-line treatment of PMBCL. Standard approach (S-CIT) was defined as R-CHOP-21/CHOP-21, with or without RT. DI-CIT were defined as regimens with increased frequency, dose, and/or number of systemic agents. We reviewed data on 4,068 patients (2,517 DI-CIT; 1,551 S-CIT) with a new diagnosis of PMBCL. Overall survival for DI-CIT patients was 88% (95% CI: 85-90) compared to 80% for the S-CIT cohort (95% CI: 74-85). Meta-regression revealed an 8% overall survival (OS) benefit for the DI-CIT group (P<0.01). Survival benefit was maintained when analyzing rituximab only regimens; OS was 91% (95% CI: 89-93) for the rituximab-DI-CIT arm compared to 86% (95% CI: 82-89) for the R-CHOP-21 arm (P=0.03). Importantly, 55% (95% CI: 43-65) of the S-CIT group received RT compared to 22% (95% CI: 15-31) of DI-CIT patients (meta-regression P<0.01). To our knowledge, this is the largest meta-analysis reporting efficacy outcomes for the front-line treatment of PMBCL. DI-CIT demonstrates a survival benefit, with significantly less radiation exposure, curtailing long-term toxicities associated with radiotherapy. As we await results of randomized prospective trials, our study supports the use of dose-intensive chemoimmunotherapy for the treatment of PMBCL.

Development and validation of a novel risk stratification model and a survival rate calculator for diffuse large B-cell lymphoma in the rituximab era: a multi-institutional cohort study

BACKGROUND

This study aimed to develop and validate a novel risk stratification model and a web-based survival rate calculator to improve discriminative and predictive accuracy for diffuse large B-cell lymphoma (DLBCL) in the rituximab era.

METHODS

We retrospectively collected pre-treatment data from 873 primary DLBCL patients who received R-CHOP-based immunochemotherapy regimens at the Cancer Hospital, Chinese Academy of Medical Sciences, from January 1, 2005, to December 31, 2018. An independent cohort of 175 DLBCL patients from Fujian Cancer Hospital was used for external validation.

FINDINGS

Age, ECOG PS, number of extranodal sites, Ann Arbor stage, bulky disease, and LDH levels were screened to develop the nomogram and web-based survival rate calculator. The C-index of the nomogram in the training, internal validation, and external validation cohorts was 0.761, 0.758, and 0.768, respectively. The risk stratification model generated based on the nomogram effectively stratified patients into three distinct risk groups. K-M survival curves demonstrated that the novel risk stratification model exhibited a superior level of predictive accuracy compared to IPI, R-IPI, and NCCN-IPI both in training and two validation cohorts. Additionally, the area under the curve (AUC) value of the novel model (0.763) for predicting 5-year overall survival rates was higher than those of IPI (0.749), R-IPI (0.725), and NCCN-IPI (0.727) in the training cohort. Similar results were observed in both internal and external validation cohort.

CONCLUSIONS

In conclusion, we have successfully developed and validated a novel risk stratification model and a web-based survival rate calculator that demonstrated superior discriminative and predictive accuracy compared to IPI, R-IPI, and NCCN-IPI in the rituximab era.

Efficacy and safety of geptanolimab (GB226) for relapsed/refractory primary mediastinal large B-cell lymphoma: an open-label phase II study (Gxplore-003)

BACKGROUND

This study aimed to assess the efficacy and safety of geptanolimab (GB226), a fully humanized, recombinant anti-programmed cell death-1 monoclonal antibody, in Chinese patients with refractory or relapsed (r/r) primary mediastinal large B-cell lymphoma (PMBCL).

METHODS

This was a multicenter, open-label, single-arm phase II study (Gxplore-003), conducted at 43 hospitals in China (NCT03639181). Patients received geptanolimab intravenously at a dose of 3 mg/kg every 2 weeks until documented confirmed disease progression, intolerable toxicity, or any other cessation criteria was met. The primary endpoint was objective response rate (ORR) in the full analysis set assessed by the independent review committee (IRC) according to the Lugano Classification 2014.

RESULTS

This study was prematurely terminated due to the slow rate of patient accrual. Between Oct 15th, 2018 and Oct 7th, 2020, 25 patients were enrolled and treated. By the data cutoff date on Dec 23rd, 2020, the IRC-assessed ORR was 68.0% (17/25; 95% confidence interval [CI] 46.5-85.1%), with the complete response rate of 24%. The disease control rate was 88% (22/25; 95%CI 68.8-97.5%). Median duration of response was not reached (NR) (95%CI, 5.62 months to NR), with 79.5% of patients having response durations of more than 12 months. Median progression-free survival was NR (95%CI, 6.83 months to NR). Treatment-related adverse events (TRAEs) were reported in 20 of 25 (80.0%) patients, and grade 3 or higher TRAEs occurred in 11 of 25 (44%) patients. No treatment-related deaths occurred. The immune-related adverse events (irAEs) of any grade were observed in 6 (24.0%) patients, and no grade 4 or grade 5 irAEs were reported.

CONCLUSION

Geptanolimab (GB226) demonstrated promising efficacy and a manageable safety profile in Chinese patients with r/r PMBCL.

Evolving therapeutic landscape of diffuse large B-cell lymphoma: challenges and aspirations

Diffuse large B-cell lymphoma (DLBCL) represents the commonest subtype of non-Hodgkin lymphoma and encompasses a group of diverse disease entities, each harboring unique molecular and clinico-pathological features. The understanding of the molecular landscape of DLBCL has improved significantly over the past decade, highlighting unique genomic subtypes with implications on targeted therapy. At the same time, several new treatment modalities have been recently approved both in the frontline and relapsed settings, ending a dearth of negative clinical trials that plagued the past decade. Despite that, in the real-world setting, issues like drug accessibility, reimbursement policies, physician and patient preference, as well as questions regarding optimal sequencing of treatment options present difficulties and challenges in day-to-day oncology practice. Here, we review the recent advances in the therapeutic armamentarium of DLBCL and discuss implications on the practice landscape, with a particular emphasis on the context of the healthcare system in Singapore.

Outcome of Primary Mediastinal Large B Cell Lymphoma Treated with RCHOP

Purpose

Primary mediastinal large B-cell Lymphoma (PMLBCL) is a rare aggressive lymphoma with unique clinical, pathological, and molecular features. The optimal frontline therapy is subject of ongoing debate. Our study aims to evaluate the outcomes of PMLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP) at King Hussein Cancer Center.

Patients and Methods

Adult patients >18 years of age with PMLBCL treated with RCHOP from January 2011 to July 2020 were identified. All demographics, disease and treatment related variables were retrospectively collected. Correlations of clinical and laboratory variables with progression-free survival (PFS) and overall survival (OS) were determined by univariate and multivariate analyses using backward stepwise Cox regression models. The PFS and OS were plotted using Kaplan‒Meier curves.

Results

49 patients were included with a median age of 29 years. 14 (28.6%) had stage III or IV, 31 (63.3%) had mediastinal bulky disease. International prognostic index (IPI) was 0-1 in 35 (71.4%). Radiotherapy was given to 32 (65.3%) patients. End of treatment (EOT) response was complete (CR) in 32 (65.3%), partial response (PR) in 8 (16.3%) and progressive disease (PD) in 9 (18.4%). Patients who achieved CR at EOT, compared favorably with those who did not in regard to 4-year OS (92.5% vs 26.9%, p=<0.001). Overall objective response to salvage chemotherapies was 26.7%. At a median follow-up of 46 months, 4-year PFS and OS were 60% and 71% respectively. In multivariate analysis, IPI > one correlated with the EOT response (p=0.009), PFS (p=0.004) and OS (p= 0.019).

Conclusion

In PMLBCL, RCHOP chemotherapy backbone in the frontline therapy is suboptimal but can be used in patients with low IPI. Adapting more intensive chemoimmunotherapy regimens may be considered for patients with high IPI. Salvage chemotherapy has limited activity in patients with relapsed or refractory disease.

Incidence and risk factors for central nervous system relapse in patients with primary mediastinal large B-cell lymphoma in the rituximab era

Central nervous system (CNS) involvement is rare in primary mediastinal large B-cell lymphoma (PMLBCL). We aimed to evaluate the incidence of CNS relapse as first treatment failure event and the effect of the induction chemotherapy regimen, central nervous system - international prognostic index (CNS-IPI) and other clinical and laboratory variables on the risk of CNS relapse in 564 PMLBCL patients treated with immunochemotherapy. Only 17 patients (3.0%) received CNS prophylaxis. During a 55-month median follow-up only 8 patients experienced CNS relapse as first event, always isolated. The 2-year cumulative incidence of CNS relapse (CI-CNSR) was 1.47% and remained unchanged thereafter. The CI-CNSR was not affected by the chemotherapy regimen (R-CHOP or R-da-EPOCH). None of the established International Prognostic Index factors for aggressive lymphomas predicted CNS relapse in PMLBCL. The 2-year CI-CNSR in patients with versus without kidney involvement was 13.3% versus 0.96% (p < 0.001); 14.3% versus 1.13% with versus without adrenal involvement (p < 0.001); and 10.2% versus 0.97% with versus without either kidney or adrenal involvement. CNS-IPI was also predictive (2-year CI-CNSR in high-risk vs. intermediate/low-risk: 10.37% vs. 0.84%, p < 0.001). However, this association may be driven mainly by kidney and/or adrenal involvement. In conclusion, in PMLBCL, CNS relapse is rare and appears to be strongly associated with kidney and/or adrenal involvement.

Malignant Tracheoparenchymal Fistula in Primary Mediastinal B-Cell lymphoma detected on Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography

Acquired tracheobronchial fistulas are a relatively uncommon complication. Among them, tracheo-mediastinal-parenchymal fistulas are particularly rare. Most of the reported cases are associated with concurrent chemoradiotherapy in lung cancer. It has not been reported in lymphomas. These fistulas are associated with high mortality due to infection and bleeding, and there is no consensus on a definitive optimal therapy. Here, we present a case of tracheoparenchymal fistula in a follow-up primary mediastinal B-cell lymphoma case. This case highlights the utility of fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in the initial diagnosis and follow-up of lymphoma. The PET/CT could show demonstrate the residual disease and differentiate it from other therapy-related benign changes.

Less Intensive Regimens May Still Be Suitable for the Initial Treatment of Primary Mediastinal B-Cell Lymphoma in Resource-Limited Settings

Primary mediastinal B-cell lymphoma (PMBCL) is an uncommon disease, consisting of 2–4% of non-Hodgkin lymphomas. Radiotherapy-free DA-EPOCH-R and R-CHOP plus radiotherapy (RT) have been the upfront standard regimens worldwide. However, performing DA-EPOCH-R in resource-constrained settings can be burdensome, especially in low/middle-income countries, where data on PMBCL are still largely unknown. We retrospectively analyzed 93 patients with PMBCL diagnosed between 2008 and 2018 with the intention of comparing the characteristics of the patients and the results obtained with each protocol and to verify if the use of less intensive chemotherapy is still possible to be used. The median age was 28 years, 59.1% were female, 42.3% were in advanced stages, and 92.1% were with bulky disease. DA-EPOCH-R (41.9%), R-CHOP (35.5%), and R-CHOEP (22.6%) were the regimens used, and no difference was observed in the characteristics of the patients. After four cycles of chemotherapy, complete response (CR), partial response (PR), and progressive disease (PD) rates were 40%, 55.7%, and 4.5%, respectively. At the end of treatment, metabolic CR and PD rates were 56.8% and 11.1%. RT was performed in 42.1% of DA-EPOCH-R, 75% of R-CHOP, and 83% of R-CHOEP, and switched PR to CR in 73.7%. Estimated 5-year PFS and OS were 77.2% and 77.4%, respectively. Only LDH levels remained independently associated with PFS, and type of treatment was not associated with OS, PFS, or relapse rate. Therefore, we conclude that in a resource-constrained setting, R-CHOP or R-CHOEP could be still safely adopted in upfront treatment for PMBCL.

Symptomatic ovarian involvement as the initial presentation of primary mediastinal large b-cell lymphoma

•

PMLBCL is an uncommon thymic B-cell neoplasm accounting for about 2.5% of NHLs.

•

Patients present with bulky mediastinal lymphadenopathy,causing dyspnea and dry cough.

•

Extrathoracic distal extranodal sites is a rare event at disease presentation.

•

This is a unique case of a young female patient with symptomatic, bulky ovarian tumor.

•

PMLBCL was finally diagnosed with a clinically silent bulky mediastinal mass.

Primary mediastinal large B- cell lymphoma (PMLBCL) is a mature aggressive B-cell lymphoma which affects mainly young and middle-aged women. The majority of patients present with bulky mediastinal lymphadenopathy. Extranodal involvement is a rare phenomenon at disease presentation. Herein, we describe a case of a young female with PMLBCL presenting with symptomatic, bulky ovarian involvement. The 23-year old patient presented at the Emergency Department with abdominal pain. The chest X-ray film revealed a mediastinal mass and CT scan revealed a large pelvic mass, possibly involving the ovaries. Due to the development of signs of acute abdomen, she was urgently transferred to the operation room where surgical resection of the right ovary and the adjacent mass was performed. The histological examination of the resected material revealed proliferation of PMLBCL cells. This is the first report in the scientific literature describing symptomatic ovarian mass as the initial mode of presentation of PMLBCL.

An Overview of Selected Rare B-Cell Lymphoproliferative Disorders: Imaging, Histopathologic, and Clinical Features

Lymphoproliferative disorders (LPD) are conditions characterized by the uncontrolled proliferation of B or T-cell lines. They encompass a wide spectrum of abnormalities, which may be broadly classified as reactive processes or malignant diseases, such as lymphoma, based on their cellular clonality and clinical behavior. While some of these disorders are rare, they may be encountered sporadically in clinical practice, causing diagnostic dilemmas owing to overlap in their clinical and imaging features with more common disorders. The updated 4th edition WHO classification of lymphoid neoplasms was released in 2016 to incorporate the rapid clinical, pathological, molecular biology and cytogenetic advances of some of these disorders. Despite these updates, very little information is presented in the literature from the radiology perspective. The aim of this article is to familiarize radiologists and other physicians with certain rare variants of B-cell lymphoproliferative disorders with a focus on imaging features of these disorders, as well as to provide an overview of some important updates contained within the new WHO classification of lymphoid neoplasms.

Primary mediastinal large B cell lymphoma

Primary mediastinal large B cell lymphoma (PMBCL) is an aggressive large B cell lymphoma originating in the mediastinum, that mainly expresses B cell surface molecules, such as CD19, CD20, CD22, andCD79a. Clinically, they are characterized by rapidly increasing anterior mediastinal masses, which can cause compression of the surrounding tissues. The diagnosis of PMBCL mainly depends on the pathological features, imaging examination and clinical features. Currently, the most commonly used therapeutic regimens are R‐CHOP and R‐EPOCH. Radiotherapy is beneficial in some patients, but it can also lead to long‐term toxicity. The research and development of novel therapies are ongoing, and some studies have achieved encouraging results, including those conducted on chimeric antigen receptor‐modified T (CAR‐T) cell therapy and anti‐PD‐1 drugs. However, randomized controlled trials with larger sample sizes are still needed. Positron emission tomography‐computed tomography (PET‐CT) is mainly used to assess the curative effect after treatment and to guide the subsequent treatment strategy.

How I Diagnose Primary Mediastinal (Thymic) Large B-Cell Lymphoma

OBJECTIVES

Primary mediastinal (thymic) large B-cell lymphoma (PMBL) is an uncommon large B-cell neoplasm recognized by the World Health Organization as a distinct entity on the basis of its unique clinical features, histogenesis, phenotype, and pathogenetic mechanisms. The diagnosis of PMBL can be challenging because of features that may overlap with other (Hodgkin and non-Hodgkin) lymphoma types. This review describes our approach to the diagnosis of PMBL.

METHODS

Two cases are presented to illustrate how we diagnose PMBL and separate PMBL from related histologic and biological mimickers, such as Hodgkin lymphoma and gray zone lymphoma.

RESULTS

A diagnosis of PMBL requires correlation of morphology and immunophenotype with clinical and staging data. Gene expression analysis is not typically performed in clinical labs but has expanded our understanding of the functional pathways underlying this disease and helped identify biomarkers that can be translated to diagnostic practice and possibly to future therapeutic options.

CONCLUSIONS

PMBL and closely related entities can pose diagnostic challenges. It is important to understand the borders between PMBL and other closely related lymphoma types so that patients receive successful primary treatment with curative intent.

Mediastinal Lymphoproliferative Disorders

Lymphoproliferative disorders comprise 50% to 60% of all mediastinal malignancies in both children and adults. Primary mediastinal involvement is rare (∼5%), whereas secondary mediastinal involvement by systemic disease is more common (10% to 25%). Primary mediastinal disease is defined as involvement by a lymphoproliferative disorder of mediastinal lymph nodes, the thymus, and/or extranodal mediastinal organs without evidence of systemic disease at presentation. In this review, the clinical, radiologic, histopathologic, immunohistochemical, and genetic features of some of the most characteristic mediastinal lymphoproliferative disorders are presented. The entities discussed here include: classic Hodgkin lymphoma with emphasis on nodular sclerosis and mixed cellularity types, and non-Hodgkin lymphomas, including primary mediastinal (thymic) large B-cell lymphoma, mediastinal gray zone lymphoma, mediastinal diffuse large B-cell lymphoma, thymic marginal zone lymphoma, mediastinal plasmacytoma, T-lymphoblastic lymphoma, and anaplastic large cell lymphoma. Although not a malignant process, hyaline vascular Castleman disease is also discussed here as this disorder commonly involves the mediastinum. Despite multiple advances in hematopathology in recent decades, the day-to-day diagnosis of these lesions still requires a morphologic approach and a proper selection of immunohistochemical markers. For this reason, it is crucial for general pathologists to be familiar with these entities and their particular clinicoradiologic presentation.

Primary Mediastinal B-Cell Lymphoma: A 2021 Update on Genetics, Diagnosis, and Novel Therapeutics

Primary mediastinal large B-cell lymphoma (PMBCL) is an aggressive B-cell lymphoma arising from thymic B-cells having clinicopathologic features distinct from systemic diffuse large B-cell lymphoma (DLBCL). PMBCL comprises 2% to 4% of all non-Hodgkin lymphomas (NHL), 7% of DLBCL and seen predominantly in young females with a median age of 35 years at diagnosis. The annual incidence of PMBCL is 0.4 per million with a 5-year survival rate exceeding 70% with improving supportive care and genetic characterization of the disease. Pathogenesis involves dysregulation of Janus kinase-signal transducer and activator of transcription (JAK-STAT), nuclear factor-kB (NF-kB) pathways and amplification of the 9p24.1 region of chromosome 9. PMBCL patients have a prolonged life expectancy necessitating the need for treatment approaches that are based on maximizing cure with minimal long-term toxicity. Due to rarity and its recognition as a distinct entity, therapeutic decisions are guided by clinical presentation, clinician and center experience, and analysis of patients with PMBCL within DLBCL registries. Historically R-CHOP has been the usual first line treatment for PMBCL followed by involved site radiotherapy (ISRT), however clinical practice varies across centers with emerging consensus to avoid upfront RT by utilizing dose intense regimens (DA-EPOCH-R) in younger and fit patients. Prognosis of relapsed refractory PMBCL not responding to salvage chemotherapy is dismal, however there are many emerging options including Brentuximab Vedotin, immune check point inhibitors and chimeric antigen receptor T-cell therapy. In this article, we focus on the pathogenesis, current and evolving treatments, and provide recommendations for optimal management of patients with PMBCL.

Identification of Very Low-Risk Subgroups of Patients with Primary Mediastinal Large B-Cell Lymphoma Treated with R-CHOP

BACKGROUND

R-CHOP can cure approximately 75% of patients with primary mediastinal large B-cell lymphoma (PMLBCL), but prognostic factors have not been sufficiently evaluated yet. R-da- EPOCH is potentially more effective but also more toxic than R-CHOP. Reliable prognostic classification is needed to guide treatment decisions.

MATERIALS AND METHODS

We analyzed the impact of clinical prognostic factors on the outcome of 332 PMLBCL patients ≤65 years treated with R-CHOP ± radiotherapy in a multicenter setting in Greece and Cyprus.

RESULTS

With a median follow-up of 69 months, 5-year freedom from progression (FFP) was 78% and 5-year lymphoma specific survival (LSS) was 89%. On multivariate analysis, extranodal involvement (E/IV) and lactate dehydrogenase (LDH) ≥2 times upper limit of normal (model A) were significantly associated with FFP; E/IV and bulky disease (model B) were associated with LSS. Both models performed better than the International Prognostic Index (IPI) and the age-adjusted IPI by Harrel's C rank parameter and Akaike information criterion. Both models A and B defined high-risk subgroups (13%-27% of patients [pts]) with approximately 19%-23% lymphoma-related mortality. They also defined subgroups composing approximately one-fourth or one-half of the patients, with 11% risk of failure and only 1% or 4% 5-year lymphoma-related mortality.

CONCLUSION

The combination of E/IV with either bulky disease or LDH ≥2 times upper limit of normal defined high-risk but not very-high-risk subgroups. More importantly, their absence defined subgroups comprising approximately one-fourth or one-half of the pts, with 11% risk of failure and minimal lymphoma-related mortality, who may not need more intensive treatment such as R-da-EPOCH.

IMPLICATIONS FOR PRACTICE

By analyzing the impact of baseline clinical characteristics on outcomes of a large cohort of patients with primary mediastinal large B-cell lymphoma homogeneously treated with R-CHOP with or without radiotherapy, we developed novel prognostic indices which can aid in deciding which patients can be adequately treated with R-CHOP and do not need more intensive regimens such as R-da-EPOCH. The new indices consist of objectively determined characteristics (extranodal disease or stage IV, bulky disease, and markedly elevated serum lactate dehydrogenase), which are readily available from standard initial staging procedures and offer better discrimination compared with established risk scores (International Prognostic Index [IPI] and age-adjusted IPI).

Antibody Therapies for Large B-Cell Lymphoma

Large B-cell lymphomas (LBCLs) constitute a subgroup of aggressive but highly curable lymphoproliferative diseases. Treatment of relapsed/refractory (R/R) patients still represents an unmet clinical need, and novel drugs and combinations are in continuous development. The pan–B cell panel of surface antigens that characterizes LBCL leads to a large umbrella of druggable targets. Monoclonal antibodies (mAbs) express their activity against lymphoma by targeting multiple tumor-specific antigens. This category consists of a number of molecules with different mechanisms of action, including naked mAbs, radioimmunoconjugates, antibody-drug conjugates, checkpoint inhibitors, and bispecific antibodies. In the last decade, apart from the well-known role of the anti-CD20 mAb rituximab, novel mAbs have led to remarkable steps forward in the treatment of R/R LBCL in monotherapy and combined with chemotherapy. Multiple studies are in development trying to bring these novel compounds into the frontline setting to empower the RCHOP effect or as alternative chemotherapy-free options for elderly/unfit patients. This review provides insight into antilymphoma mAbs, focused on the efficacy and safety of the main molecules approved or in development for LBCL andperspectives on the treatment of this disease.

Primary Mediastinal B-Cell Lymphoma: Novel Precision Therapies and Future Directions

Primary mediastinal large B-cell lymphoma (PMBCL) is a distinct clinicopathologic disease from other types of diffuse large B-cell lymphoma (DLBCL) with unique prognostic features and limited availability of clinical data. The current standard treatment for newly diagnosed PMBCL has long been dependent on a dose-intensive, dose-adjusted multi-agent chemotherapy regimen of rituximab plus etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin (DA-R-EPOCH). Recent randomized trials have provided evidence that R-CHOP followed by consolidation radiotherapy (RT) is a valuable alternative option to first-line treatment. For recurrent/refractory PMBCL (rrPMBCL), new drugs such as pembrolizumab and CAR-T cell therapy have proven to be effective in a few studies. Positron emission tomography-computed tomography (PET-CT) is the preferred imaging modality of choice for the initial phase of lymphoma treatment and to assess response to treatment. In the future, baseline quantitative PET-CT can be used to predict prognosis in PMBCL. This review focuses on the pathology of PMBCL, underlying molecular basis, treatment options, radiotherapy, targeted therapies, and the potential role of PET-CT to guide treatment choices in this disease.

AYA Considerations for Aggressive Lymphomas

PURPOSE OF REVIEW

Lymphoma is the one of the most common cancer diagnoses among adolescents and young adults (AYAs) aged 15-39. Despite significant advances in outcomes observed in older adults and younger children, improvements in AYAs have lagged behind. The reasons for this are likely multifactorial including disparities in access to health insurance, low rates of enrollment to clinical trials, potential differences in disease biology, and unique psychosocial challenges. Here we will review Hodgkin lymphoma (HL) and primary mediastinal B cell lymphoma (PMBCL), two of the most common aggressive lymphomas that occur in AYAs. We will discuss the current knowledge about disease biology in AYAs, adult and pediatric treatment strategies, novel targeted therapies, and ongoing AYA clinical trials in these lymphoma subtypes. We also will review unique considerations for treatment-related toxicities in AYAs and psychosocial issues relevant to this population.

RECENT FINDINGS

Pediatric and adult trials in HL and PMBCL have demonstrated that treatment with dose-intense chemotherapeutic regimens with or without radiation results in high cure rates but can also be associated with long-term toxicity which must be considered in this young population. Novel targeted agents such as the antibody-drug conjugate brentuximab vedotin and/or antibodies targeted against PD-1/PD-L1 have demonstrated activity in the relapsed setting and are currently being evaluated in the upfront setting, which may reduce our reliance on therapies associated with long-term toxicity. AYA-focused clinical trials are currently underway to better elucidate the optimal therapy for lymphomas in this age group. There is an urgent need for clinical trials including AYAs in order to increase the knowledge of age-specific outcomes, toxicities, disease biology, and the need to develop comprehensive AYA care models that meet the unique and complex care needs of this patient population.

Outcomes of Patients with Primary Mediastinal B-Cell Lymphoma Treated with Dose Adjusted R-EPOCH Regimen: A Single Centre Experience

Introduction

Primary Mediastinal B cell lymphoma (PMBCL) is a biologically and clinically distinct subset of diffuse large B cell lymphoma. We analysed the outcomes of our cohort of PMBCL patients treated with Dose adjusted (DA)-R-EPOCH regimen.

Patients and Methods

This is a retrospective analysis of consecutive PMBCL patients who received chemotherapy consisting of DA-R-EPOCH with filgrastim support. Survival analysis was done using Kaplan-Meier method. All calculations were performed using SPSS version 20 for windows.

Results

A total of 43 consecutive suspected PMBCL patients were reviewed for this study, 6 patients were excluded as diagnosis of PMBCL could not be established. All patients except one (97.3%) received 6 cycles of R-DA-EPOCH regimen. Median age of the patients was 27 years (range 15-58). Bulky disease (> 7 cm) was present in 97% patients and 54% patients had extranodal disease. With a median follow up of 40 months, 3-year overall survival was 80.6% (95% CI: 74.0-87.2). The 3-year event free survival was 78.4% (95% CI: 71.6-85.2). There were 6 (16.2%) relapses, 1 (2.7%) primary progression and 7 (23%) deaths. Mediastinal radiotherapy was administered to 17 (45.9%) patients. All the deaths were due to disease progression. Grade III/IV toxicities were seen in 28 (75.7%) patients, febrile neutropenia being the most common one.

Conclusions

DA-R-EPOCH regimen is an effective and tolerable regimen in PMBCL patients even with adverse features.

The effect of bulky mass on prognosis in diffuse large-B-cell lymphoma: still poor?

The introduction of rituximab to the CHOP protocol has demonstrated an improvement in PFS and OS in DLBCL patients with both early and advanced stages. Most studies in the pre-rituximab period indicated that bulky disease has an unfavorable impact on clinical outcomes of DLBCL. The effect of bulky mass on the outcome of DLBCL patients undergoing R-CHOP therapy remained uncertain. One-hundred-twelve newly diagnosed DLBCL patients aged 18 and older were enrolled in the study. Patients were divided into groups-based presence of bulky disease. 56 patients with bulky disease and their age, gender, ECOG score, Ann Arbor stage, immunohistochemical origin, treatment, radiotherapy and comorbidity 1:1 matched 56 control patients with non-bulky disease included. Overall response rate at end of treatment was similar among groups (p = 0.1). Patients with bulky disease and non-bulky disease were comparable regarding overall survival (p = 0,9). All cohort investigated for predictors for survival, after multivariate analysis, ECOG score, Ann arbor stage, IPI score and LDH level were found significant. Here, we found no impact of bulky disease on remission and survival. We believe, with increasing available data, poor prognostic value of bulky disease will be weakening in the rituximab era.

Positron emission tomography after response to rituximab-CHOP in primary mediastinal large B-cell lymphoma: impact on outcomes and radiotherapy strategies

End-of-treatment (EoT) PET/CT is used as a guide to omit radiotherapy (RT) patients with primary mediastinal large B-cell lymphoma (PMBCL). We present the mature and extended results of a retrospective study evaluating the prognostic significance of EoT-PET/CT after adequate response to R-CHOP. Among 231 consecutive PMLBCL patients, 182 underwent EoT-PET/CT and were evaluated according to the Deauville 5-point scale (D5PS) criteria. Freedom from progression (FFP) was measured from the time of PET/CT examination. Among 182 patients, 72 (40%) had D5PS score 1 (D5PSS-1), 33 (18%) had 2, 28 (15%) had 3, 29 (16%) had 4, and 20 (11%) had 5. The 5-year FFP was 97, 94, 92, 82, and 44% for D5PSS-1, D5PSS-2, D5PSS-3, D5PSS-4, and D5PSS-5, respectively. Among 105 patients with unequivocally negative PET/CT (D5PSS-1/D5PSS-2), 49 (47%) received RT (median dose 3420 cGy) and 56 (53%) did not with relapses in 0/49 vs. 4/56 patients (2 mediastinum and 2 isolated CNS relapses).The 5-year FFP for those who received RT or not was 100% versus 96%, when isolated CNS relapses were censored (p = 0.159). Among D5PSS-3 patients (27/28 irradiated-median dose 3600 cGy), the 5-year FFP was 92%. The 5-year FFP for D5PSS-4 and D5PSS-5 was 82 and 44%; 44/49 patients received RT (median dose 4000 and 4400 cGy for D5PSS-4 and D5PSS-5). Our study supports the omission of RT in a sizeable fraction of PET/CT-negative patients and definitely discourages salvage chemotherapy and ASCT in patients with PMLBCL who conventionally respond to R-CHOP, solely based on PET/CT positivity in the absence of documented progressive or multifocal disease. The persistence of positive PET/CT with D5PSS < 5 after consolidative RT should not trigger the initiation of further salvage chemotherapy in the absence of conventionally defined PD.

Treatment patterns, healthcare resource utilization, and costs of patients diagnosed with primary mediastinal B-cell lymphoma in the United States

AIMS

With the advent of ICD-10-CM codes for PMBCL on 10/01/2015, assessment of treatment patterns and healthcare burden among US patients is possible. This study sought to describe the real-world treatment patterns and economic outcomes of patients with PMBCL.

METHODS

Data from the Optum Clinformatics DataMart database was used (January 2013-March 2018). Patients with a first PMBCL ICD-10-CM diagnosis (with or without an antecedent ICD-10-CM diagnosis of DLBCL/other lymphoma, which may have been assigned before PMBCL confirmation) after 10/01/2015 (index date) and no ICD-9-CM diagnosis code for unspecified PMBCL/DLBCL were identified as incident patients. Those with PMBCL ICD-10-CM and unspecified ICD-9-CM diagnosis for PMBCL/DLBCL before 10/01/2015 (index date) were identified as prevalent patients. Patients were observed from the index date up to the earliest among death, end of data availability, or end of continuous health plan enrollment. An adapted algorithm was used to identify lines of therapy (LOT).

RESULTS

Among 118 incident and 30 prevalent PMBCL patients, 14% and 20% of patients received ≥2 LOTs, respectively. In incident patients, 48% received ≥1 LOT, 14% ≥2, and 4% ≥3 LOTs. Among prevalent patients, 63% received ≥1 LOT and 20% ≥2 LOTs. The most frequently recorded 1 L therapy was R-CHOP both among incident and prevalent patients. Mean total healthcare costs for incident and prevalent patients were $149,340 and $92,799 per patient per year, respectively, with higher costs ≤12 months ($187,241 and $167,553). Outpatient costs were the main driver (accounting for 60.5% and 64.6% for incident and prevalent patients, respectively).

LIMITATIONS

Potential underuse of ICD-10-CM codes shortly after discontinuation of ICD-9-CM codes in 01/2015; regimens identified for each LOT using the claims-based algorithm may not reflect the regimen administered.

CONCLUSION

The multiple LOTs necessary for a sizeable minority of patients and the high costs of care highlight the significant unmet needs of PMBCL patients.

Treatment and outcomes of primary mediastinal B cell lymphoma: a three-decade monocentric experience with 151 patients

Primary mediastinal B cell lymphoma is a rare entity and often should be promptly treated as a hematological emergency: The initial treatment decision is crucial for the management of this disease. An observational retrospective study was conducted with the aim to improve information on treatment and outcomes of primary mediastinal B cell lymphoma in real practice. After 12 cycles of MACOP-B regimen (methotrexate, doxorubicin, cyclophosphamide, vincristine, bleomycin , and prednisone) with or without rituximab, 120 patients out of 151 (79.5%) achieved a complete response and 12 (7.9%) a partial response leading to a global response of 87.4%. The 21-year overall survival is 82.6%; progression-free and disease-free survivals are 69.3% and 86.4%, respectively. Regarding the role of radiotherapy (RT), patients with a negative PET scan after MACOP-B did not undergo RT: One out of these 48 (2.1%) showed a relapse at 11 months. All relapsed/refractory patients who achieved a response with checkpoint inhibitors are still in continuous complete response with a median follow-up of 14 months. Data that we have gathered over a 30-year experience in the treatment of primary mediastinal B cell lymphoma patients clearly indicate that a third-generation chemotherapy regimen such as MACOP-B is feasible and easily deliverable on an outpatient basis. Regarding the unmet medical need of relapsed/refractory patients, new encouraging results occurred with the advent of the checkpoint inhibitors.

Saudi Lymphoma Group's Clinical Practice Guidelines for Diagnosis, Management and Follow-up of Patients with Various Types of Lymphoma during the Coronavirus Disease 2019 Pandemic

The Saudi Lymphoma Group had previously published recommendations on the management of the major subtypes of lymphoma. However, the effect the currently ongoing coronavirus disease 2019 (COVID-19) pandemic has on the management of patients with lymphoma has been paramount. Therefore, the Saudi Lymphoma Group has decided to provide clinical practice guidelines for the diagnosis, management and follow-up of patients with various types of lymphoma during the COVID-19 pandemic.

Current Challenges in Providing Good Leukapheresis Products for Manufacturing of CAR-T Cells for Patients with Relapsed/Refractory NHL or ALL

Background: T lymphocyte collection through leukapheresis is an essential step for chimeric antigen receptor T (CAR-T) cell therapy. Timing of apheresis is challenging in heavily pretreated patients who suffer from rapid progressive disease and receive T cell impairing medication. Methods: A total of 75 unstimulated leukaphereses were analyzed including 45 aphereses in patients and 30 in healthy donors. Thereof, 41 adult patients with Non-Hodgkin’s lymphoma (85%) or acute lymphoblastic leukemia (15%) underwent leukapheresis for CAR-T cell production. Results: Sufficient lymphocytes were harvested from all patients even from those with low peripheral lymphocyte counts of 0.18/nL. Only four patients required a second leukapheresis session. Leukapheresis products contained a median of 98 × 10⁸ (9 - 341 × 10⁸) total nucleated cells (TNC) with 38 × 10⁸ (4 - 232 × 10⁸) CD3+ T cells. Leukapheresis products from healthy donors as well as from patients in complete remission were characterized by high TNC and CD3+ T lymphocyte counts. CAR-T cell products could be manufactured for all but one patient. Conclusions: Sufficient yield of lymphocytes for CAR-T cell production is feasible also for patients with low peripheral blood counts. Up to 12–15 L blood volume should be processed in patients with absolute lymphocyte counts ≤ 1.0/nL.

Lymphomas of the Mediastinum and Their Differential Diagnosis

Lymphoma is the most common malignancy involving the mediastinum but can be challenging to diagnose on small biopsy specimens. This review provides a pattern-based approach to help triage small tissue samples for the diagnosis of mediastinal lymphoid proliferations, with focus on the main primary mediastinal lymphomas. The use of ancillary studies is highlighted, along with considerations to avoid misdiagnosis and scenarios to request additional tissue.

Prognostic factors, therapeutic approaches, and distinct immunobiologic features in patients with primary mediastinal large B-cell lymphoma on long-term follow-up

Primary mediastinal large B-cell lymphoma (PMBCL) is a rare and distinct subtype of diffuse large B-cell lymphoma (DLBCL) without prognostic factors or a single standard of treatment clearly defined. In this study we performed retrospective analysis for clinical outcomes of 166 patients with PMBCL. In overall PMBCL, higher International Prognostic Index, stage, Ki-67 proliferation index, and positron emission tomography (PET) maximum standardized uptake values (SUVmax) at diagnosis were significantly associated with poorer survival, whereas MUM1 expression and higher peripheral blood lymphocyte/monocyte ratios were significantly associated with better survival. Patients who received R-HCVAD or R-EPOCH had better clinical outcome than did those who received the standard treatment R-CHOP. Treatment response and end-of-treatment PET SUVmax had remarkable correlations with survival outcome. In patients with refractory or relapsed PMBCL, stem cell transplant significantly improved overall survival. PMBCL had distinct gene expression signatures compared with overall DLBCL–NOS but not with DLBCL with PD-L1/PD-L2 amplification. PMBCL also showed higher PD-L2 expression in B-cells, lower PD-1 expression in T-cells, and higher CTLA-4 expression in T-cells and distinct miRNA signatures compared with DLBCL-NOS. The prognostic factors, effectiveness of treatment, transcriptional and epigenetic signatures, and immunologic features revealed by this study enrich our understanding of PMBCL biology and support future treatment strategy.

Primary Mediastinal Large B-Cell Lymphoma: A Review for Radiologists

OBJECTIVE. The purpose of this article is to provide a primer for radiologists focused on integrating the radiologic, pathologic, and clinical features of primary mediastinal large B-cell lymphoma (PMLBCL). CONCLUSION. PMLBCL is a unique subtype of lymphoma that poses diagnostic and therapeutic challenges to the fields of radiology and oncology. Knowledge of this distinctive clinical-pathologic entity and its associated imaging and clinical features is critical for radiologists.

Front-Line Treatment of High Grade B Cell Non-Hodgkin Lymphoma

PURPOSE OF REVIEW

Rituximab-based chemoimmunotherapy has resulted in a marked improvement in the survival of diffuse large B cell lymphoma (DLBCL). We reflect upon the history front-line (1L) therapy and highlight advances in management.

RECENT FINDINGS

Since the introduction of R-CHOP, the majority of randomized studies in the front-line treatment of DLBCL have failed to show a benefit. Such studies have involved treatment intensification, adding novel agents to the R-CHOP backbone and targeting such novel agents to biologically defined subgroups. R-CHOP therefore remains standard-of-care for most but new insights into the molecular biology of these diseases, and the development of active targeted molecules offers promise for the future. Accumulating evidence in the very elderly suggests dose attenuation does not compromise survival. Intensification in primary mediastinal B cell lymphoma may avoid the need for radiotherapy, but must be balanced against the risks. PET-CT- and ctDNA-based response assessment may now enable response adapted therapy and early prognostication, improving patient selection and potentially outcomes. Novel technologies and therapies in combination with novel molecular diagnostics will likely become the standard-of-care approach for the personalized therapy of DLBCL but need to be proven in well-designed and conducted randomized trials.

Hitting back at lymphoma: How do modern diagnostics identify high-risk diffuse large B-cell lymphoma subsets and alter treatment?

Diffuse large B-cell lymphoma (DLBCL) is a clinically and biologically heterogeneous disease. Diagnostic tools in the clinic can now identify distinct subsets characterized by unique molecular features, which are increasingly transforming how these patients are managed. Activated B-cell-like DLBCL is characterized by NF-κB activation and chronic B-cell receptor signaling and may be targeted with lenalidomide or ibrutinib in the relapsed setting. Germinal center-like DLBCL is enriched for activating EZH2 mutations, and encouraging activity has been observed for the EZH2 inhibitor tazemetostat, which now has a fast-track US Food and Drug Administration designation. Double-hit lymphoma is a high-grade B-cell lymphoma characterized by translocations of MYC and BCL2 and/or BCL6 and carries a poor prognosis. Intensive chemoimmunotherapy strategies appear to be superior to standard R-CHOP (rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone) as initial therapy, and anti-CD19 chimeric antigen receptor T cells are inducing remission in patients with relapsed/refractory disease who previously had few available options. Primary mediastinal (thymic) large B-cell lymphoma is a molecularly distinct large-cell lymphoma with clinical and molecular features that overlap with those of classical Hodgkin lymphoma. R-CHOP has been associated with an unacceptably high rate of primary treatment failure in this young population, whereas dose-adjusted EPOCH-R (etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin plus rituximab) produces durable remissions without the need for radiotherapy in most patients. For relapsed/refractory disease, immune checkpoint inhibitors targeting PD-1 have shown promising activity in chemotherapy-refractory disease, as have anti-CD19 chimeric antigen receptor T cells. Additional therapeutic targets, including JAK2, continue to be evaluated. The identification of discrete biological subsets is steadily moving us away from a "one-size-fits-all" approach in DLBCL.

Real world experience of R-CHOP with or without consolidative radiotherapy vs DA-EPOCH-R in the first-line treatment of primary mediastinal B-cell lymphoma

Primary mediastinal large B‐cell lymphoma (PMBCL) is a distinct clinico‐pathological subtype of diffuse large B‐cell lymphoma with unclear prognostic factors and limited clinical data. Optimal treatment and role for radiotherapy is not fully defined. We performed a multicenter retrospective review of 124 patients with newly diagnosed PMBCL between 2001 and 2016. Treatment regimens were R‐CHOP (n = 41), R‐CHOP + RT (n = 37), and DA‐EPOCH‐R (n = 46). 6% (n = 3) in the DA‐EPOCH‐R group received RT. With a median follow up of 45 months, the overall 5‐year OS and PFS was 89.4% and 82.4%, respectively. The type of chemo‐radiotherapy regimen, B symptoms and Ann‐Arbor staging showed a significant association with OS on univariate analysis but only B symptoms remained prognostic (P = 0.012) after multivariate analysis. The chemo‐radiotherapy regimen, Japanese IPI and Ann‐Arbor stage was significantly associated with PFS in univariate analysis, but only chemo‐radiotherapy regimen remained significant (P = 0.02) after multivariate analysis. Patients who received R‐CHOP + RT or DA‐EPOCH‐R had better PFS than those receiving R‐CHOP alone, with 5‐year PFS of 90% vs 88.5% vs 56%, respectively (P = 0.02). In the subgroup analysis of patients with bulk (n = 71), R‐CHOP alone (n = 21) had inferior 5‐year PFS 56.6% compared to those who received R‐CHOP + RT (n = 23) 91.3% or DA‐EPOCH‐R (n = 27) 92.6% (P = 0.007). In contrast, in patients without bulk (n = 42), there was no impact of treatment regimen on PFS (P = 0.25). In conclusion, R‐CHOP + RT and DA‐EPOCH‐R provide excellent outcomes in patients with PMBCL. In patients with bulky disease, the use of DA‐EPOCH‐R may be preferable as it allows omission of RT without reduction in efficacy.

Role of Radiation Therapy in Younger and Older Adults with Primary Mediastinal Large B Cell Lymphoma in Rituximab Era: A U.S. Population-Based Analysis

The role of mediastinal radiotherapy (RT) in primary mediastinal large B cell lymphoma is controversial. We used the Surveillance, Epidemiology and End Results program 18 database to identify the role after rituximab approval. Among 474 patients included, 65.8% were 18-39 years old and 34.2% were 40-59 years old; 45.8% received RT. Univariate analysis showed that disease stage and race could affect survival. After adjusting for stage and race, RT was correlated with prognosis in patients aged 40-59 years (none/unknown vs. RT, hazard ratio = 2.898, p = 0.034). However, in patients aged 18-39 years, this impact was not significant. Omission of RT in selected young patients may be considered.

Biology and therapy of primary mediastinal B-cell lymphoma: current status and future directions

Primary mediastinal B-cell lymphoma (PMBCL) is a distinct disease closely related to classical nodular sclerosing Hodgkin lymphoma. Conventional diagnostic paradigms utilising clinical, morphological and immunophenotypical features can be challenging due to overlapping features with other B-cell lymphomas. Reliable diagnostic and prognostic biomarkers that are applicable to the conventional diagnostic laboratory are largely lacking. Nuclear factor kappa B (NF-κB) and Janus kinase/signal transducers and activators of transcription (JAK-STAT) signalling pathways are characteristically dysregulated in PMBCL and implicated in several aspects of disease pathogenesis, and the latter pathway in host immune evasion. The tumour microenvironment is manipulated by PMBCL tumours to avoid T-cell mediated destruction via strategies that include loss of tumour cell antigenicity, T-cell exhaustion and activation of suppressive T-regulatory cells. R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) and DA-EPOCH-R (dose-adjusted etoposide, prednisolone, vincristine, cyclophosphamide, doxorubicin, rituximab) are the most common first-line immunochemotherapy regimens. End of treatment positron emission tomography scans are the recommended imaging modality and are being evaluated to stratify patients for radiotherapy. Relapsed/refractory disease has a relatively poor outcome despite salvage immunochemotherapy and subsequent autologous stem cell transplantation. Novel therapies are therefore being developed for treatment-resistant disease, targeting aberrant cellular signalling and immune evasion.

How I treat primary mediastinal B-cell lymphoma

The World Health Organization now recognizes primary mediastinal B-cell lymphoma (PMBCL) as a unique clinical and biologic entity. PMBCL is distinct from other B-cell non-Hodgkin lymphoma subtypes and has features that overlap with classical Hodgkin lymphoma, including a peak incidence in the adolescent and young adult population, mediastinal presentation of disease, and molecular alterations in JAK2 and programmed death ligands. Because PMBCL is rare, there are few prospective clinical trials to guide therapy, resulting in no single standard of care. Given the long life expectancy of survivors of PMBCL, treatment approaches must balance maximizing cure while minimizing long-term toxicity. In this article, I review my approach to the treatment of PMBCL, incorporating data from adult and pediatric studies, as well as recent advances in our understanding of the molecular basis of PMBCL.

Serum IL-6, IL-8, IL-10 and Beta2-Microglobulin in Association with International Prognostic Index in Diffuse Large B Cell Lymphoma

Aims and Background

Diffuse large B-cell lymphoma displays striking heterogeneity at clinical, genetic and molecular levels. The International Prognostic Index is useful to predict the outcome of diffuse large B-cell lymphoma patients. However, patients with identical International Prognostic Index values in clinical practice exhibit marked variability in survival, suggesting the presence of significant residual heterogeneity within each category. Since cytokines such as interleukin-6, -8 and -10 play important roles in the pathogenesis of lymphomas, and plasma level of beta2-microglobulin is associated with the outcome of patients with diffuse large B-cell lymphoma, the aim of the present study was to determine whether these parameters combined with the International Prognostic Index would better stratify these patients to predict their prognosis.

Patients and Methods

The study included 46 untreated diffuse large B-cell lymphoma patients.

Results

All study parameters (International Prognostic Index, Ann Arbor stage, extra-nodal involvement, performance status, lactate dehydrogenase, beta2-microglobulin, interleukin-6 and -10, and response to therapy) except for patient age and serum interleukin-8 level were associated with overall survival. In addition, the International Prognostic Index was strongly correlated with beta2-microglobulin, interleukin-6, -8 and -10, and when combined these parameters significantly better stratified patients according to survival. On multivariate analysis, therapeutic response to the primary treatment, elevated interleukin-6 and -10 levels, and the International Prognostic Index were significant predictors of overall survival.

Conclusions

Our data imply that interleukins and beta2-microglobulin evaluation should be used in association with the International Prognostic Index to define prognostic subgroups in diffuse large B-cell lymphoma patients.

R-CHOP versus dose-adjusted R-EPOCH in frontline management of primary mediastinal B-cell lymphoma: a multi-centre analysis

Primary mediastinal (thymic) large B-cell lymphoma (PMBCL) is an uncommon subtype of non-Hodgkin lymphoma (NHL) that presents with a mediastinal mass and has unique clinicopathological features. Historically, patients with PMBCL were treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) chemotherapy ± involved field radiation. Since a phase II trial, published in April 2013, demonstrated excellent results using dose-adjusted (DA) R-EPOCH (rituximab, etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin), this treatment has gained popularity. We performed a retrospective, multicentre analysis of patients aged ≥18 years with PMBCL since January 2011. Patients were stratified by frontline regimen, R-CHOP versus DA-R-EPOCH. 132 patients were identified from 11 contributing centres (56 R-CHOP and 76 DA-R-EPOCH). The primary outcome was overall survival. Secondary outcomes included progression-free survival, complete response (CR) rate, and rates of treatment-related complications. Demographic characteristics were similar in both groups. DA-R-EPOCH use increased after April 2013 (79% vs. 45%, P < 0·001), and there was less radiation use after DA-R-EPOCH (13% vs. 59%, P < 0·001). While CR rates were higher with DA-R-EPOCH (84% vs. 70%, P = 0·046), these patients were more likely to experience treatment-related toxicities. At 2 years, 89% of R-CHOP patients and 91% of DA-R-EPOCH patients were alive. To our knowledge, this represents the largest series comparing outcomes of R-CHOP to DA-R-EPOCH for PMBCL.

Primary mediastinal B-cell lymphoma: biology and evolving therapeutic strategies

Primary mediastinal B-cell lymphoma (PMBCL) is recognized as a distinct clinicopathologic entity that predominantly affects adolescents and young adults and is more common in female subjects. Although PMBCL is considered to be a subtype of diffuse large B-cell lymphoma, its clinical, morphologic, and biological characteristics overlap significantly with those of nodular sclerosing Hodgkin lymphoma (NSHL). Over the past few years, the shared biology of these 2 entities has been highlighted in several studies, and mediastinal gray zone lymphoma, with features intermediate between PMBCL and NSHL, has been recognized as a unique molecular entity. Although there is a lack of consensus about the optimal therapeutic strategy for adolescent and young adult patients newly diagnosed with PMCBL, highly curative strategies that obviate the need for mediastinal radiation are favored by most. Progress in understanding the biology of PMBCL and its close relationship to NSHL have helped pave the way for the investigation of novel approaches such as immune checkpoint inhibition. Other strategies such as adoptive T-cell therapy and targeting CD30 are also being studied.