Racial patterns of patients with primary mediastinal large B-cell lymphoma: SEER analysis

Major impact of prognosis by age and sex in patients with primary mediastinal large B‑cell lymphoma

The effective prognostic factors for primary mediastinal large B-cell lymphoma (PMLBCL) vary among published studies. The aim of the present study was to explore the factors influencing the overall survival (OS) and progression-free survival (PFS) of patients with PMLBCL at a single institute in Taiwan. This retrospective study was conducted to analyze the prognostic impact of age, sex, disease stage, International Prognostic Index (IPI) score, treatment modality and initial response. A total of 72 patients with a median age of 28 years were included in the study. The mean OS and PFS were 171.40 and 159.77 months, respectively. Female sex, age ≤60 years, receiving radiotherapy (RT) and achieving a complete response were found to be associated with a significantly improved OS and PFS. In addition, high-intensity chemotherapy and an IPI score ≤1 were associated with longer OS, and early-stage disease was associated with a PFS superior to that of advanced-stage disease. The predictive value of IPI is limited in PMLBCL. Therefore, it is necessary to develop a novel prognostic system. The present study revealed the impact of sex on prognosis and, therefore, this factor should be considered in future prognostic evaluations. Since a complete post-treatment response was found to be important, high-intensity chemotherapy is recommended. However, low-intensity treatment followed by RT consolidation appears to be a feasible approach in elderly patients.

Updates in the Management of Primary Mediastinal B Cell Lymphoma

Primary mediastinal B cell lymphoma (PMBCL) is considered a distinct pathology according to the WHO classification of lymphoid malignancies. Patients have a better prognosis after the addition of Rituximab to anthracycline-based chemotherapy. The role of consolidative radiotherapy is controversial after the approval of dose-adjusted R-EPOCH and the selection of patients to undergo radiotherapy is based on end-of-therapy PET CT. In the relapsed/refractory setting, new approved drugs and other under investigation have improved patient outcomes. This review summarizes the different treatment modalities in (PMBCL) in the frontline and the relapsed/refractory settings.

Nivolumab combined with brentuximab vedotin for R/R primary mediastinal large B-cell lymphoma: a 3-year follow-up

Patients with relapsed/refractory primary mediastinal large B-cell lymphoma (R/R PMBL) have poor responses to salvage therapy. Nivolumab and brentuximab vedotin (BV) showed promising early efficacy in patients with R/R PMBL in the phase 1/2 open-label, multicenter CheckMate 436 study; we report safety and efficacy findings from the 3-year follow-up. Patients who were eligible were aged ≥15 years with R/R PMBL previously treated with either high-dose chemotherapy plus autologous hematopoietic cell transplantation (HCT) or ≥2 prior multiagent chemotherapies, and had Eastern Cooperative Oncology Group performance status scores of 0 to 1 and CD30 expression of ≥1%. Patients were treated with nivolumab 240 mg and BV 1.8 mg/kg once every 3 weeks until disease progression or unacceptable toxicity. Primary end point was objective response rate (ORR); secondary end points included complete response rate, duration of response, progression-free survival (PFS), and overall survival (OS). Safety was monitored throughout. At final database lock (30 March 2022), 29 patients had received nivolumab plus BV; median follow-up was 39.6 months. Investigator-assessed ORR was 73.3%; median time to response was 1.3 months (range, 1.1-4.8). Median PFS was 26.0 months; median OS was not reached. PFS and OS rates at 24 months were 55.5% (95% confidence interval [CI], 32.0-73.8) and 75.5% (95% CI, 55.4-87.5), respectively. The most frequently occurring grade 3/4 treatment-related adverse event was neutropenia. Consolidative HCT was received by 12 patients, with a 100-day complete response rate of 100.0%. This 3-year follow-up showed long-term efficacy for nivolumab plus BV in R/R PMBL, with no new safety signals. This trial was registered at www.clinicaltrials.gov as #NCT02581631.

Sex differences in lymphoma incidence and mortality by subtype: A population-based study

It is well established that the male sex is associated with increased risk for, as well as poorer survival of, most cancers. A similar pattern has been described in lymphomas but has not yet been comprehensively assessed. In this nationwide population-based cohort study, we used the Swedish Lymphoma Register to investigate sex differences in lymphoma subtype incidence and excess mortality in adults (age 18-99) diagnosed in 2000-2019. Male-to-female incidence rate ratios (IRRs) and excess mortality ratios (EMRs) adjusted for age and calendar year were predicted using Poisson regression. We identified 36 795 lymphoma cases, 20 738 (56.4%) in men and 16 057 (43.6%) in women. Men were at significantly higher risk of 14 out of 16 lymphoma subtypes with IRRs ranging from 1.15 (95% confidence interval [CI] 1.09-1.22) in follicular lymphoma to 5.95 (95% CI 4.89-7.24) in hairy cell leukemia. EMRs >1 were seen in 13 out of 16 lymphoma subtypes indicating higher mortality in men, although only statistically significant for classical Hodgkin lymphoma 1.26 (95% CI 1.04-1.54), aggressive lymphoma not otherwise specified 1.29 (95% CI 1.08-1.55), and small lymphocytic lymphoma 1.52 (95% CI 1.11-2.07). A corresponding analysis using data from the Danish Lymphoma Register was performed with comparable results. In conclusion, we demonstrate a significantly higher incidence and trend toward higher mortality in men for most lymphoma subtypes. Future studies with large patient material that include detailed clinicopathological prognostic factors are warranted to further delineate and explain sex differences in lymphoma survival to enable optimal management of lymphoma patients regardless of sex.

Outcomes after first-line immunochemotherapy for primary mediastinal B-cell lymphoma: a LYSA study

Primary mediastinal B-cell lymphoma (PMBL) is a rare type of aggressive lymphoma typically affecting young female patients. The first-line standard of care remains debated. We performed a large multicenter retrospective study in 25 centers in France and Belgium to describe PMBL patient outcomes after first-line treatment in real-life settings. A total of 313 patients were enrolled and received rituximab (R) plus ACVBP (doxorubicin, cyclophosphamide, vindesine, bleomycin, and prednisone) (n = 180) or CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) delivered every 14 days (R-CHOP14, n = 76) or 21 days (R-CHOP21, n = 57) and consolidation strategies in modalities that varied according to time and institution, mainly guided by positron emission tomography. Consolidation autologous stem cell transplantation was performed for 46 (25.6%), 24 (31.6%), and 1 (1.8%) patient in the R-ACVBP, R-CHOP14, and R-CHOP21 groups, respectively (P < .001); only 17 (5.4%) patients received mediastinal radiotherapy. The end-of-treatment complete metabolic response rates were 86.3%, 86.8%, and 76.6% (P = .23) in the R-ACVBP, R-CHOP14, and R-CHOP21 groups. The median follow-up was 44 months, and the R-ACVBP, R-CHOP14, and R-CHOP21 three-year progression-free survival probabilities were 89.4% (95% confidence interval [CI], 84.8-94.2), 89.4% (95% CI, 82.7-96.6), and 74.7% (95% CI, 64-87.1) (P = .018). A baseline total metabolic tumor volume (TMTV) ≥360 cm3 was associated with a lower progression-free survival (hazard ratio, 2.18; 95% CI, 1.05-4.53). Excess febrile neutropenia (24.4% vs 5.3% vs 5.3%; P < .001) and mucositis (22.8% vs 3.9% vs 1.8%; P < .001) were observed with R-ACVBP compared with the R-CHOP regimens. Patients with PMBL treated with dose-dense immunochemotherapy without radiotherapy have excellent outcomes. R-ACVBP acute toxicity was higher than that of R-CHOP14. Our data confirmed the prognostic importance of baseline TMTV.

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 in the Positron-Emission Tomography Era Executive Summary of the American Radium Society Appropriate Use Criteria

PURPOSE

Primary mediastinal B cell lymphoma (PMBCL) is a highly curable subtype of non-Hodgkin lymphoma that is diagnosed predominantly in adolescents and young adults. Consequently, long-term treatment-related morbidity is critical to consider when devising treatment strategies that include different chemoimmunotherapy strategies with or without radiation therapy. Furthermore, adaptive approaches using the end-of-chemotherapy (EOC) positron emission tomography (PET)/computed tomography (CT) scanning may help to determine which patients may benefit from additional therapies. We aimed to develop evidence-based guidelines for treating these patients.

METHODS AND MATERIALS

We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline using the PubMed database. The ARS expert committee, composed of radiation oncologists, hematologists, and pediatric oncologists, developed consensus guidelines using the modified Delphi framework.

RESULTS

Nine studies met the full criteria for inclusion based on reporting outcomes on patients with primary mediastinal B cell lymphoma with EOC PET/CT response scored with the 5-point Deauville scale. These studies formed the evidence for these guidelines in managing patients with PMBCL according to the EOC PET response, including after a 5-point Deauville scale of 1 to 3, 4, or 5, and for patients with relapsed and refractory disease. The expert group also developed guidance on radiation simulation, treatment planning, and plan evaluation based on expert opinion.

CONCLUSIONS

Various treatment approaches exist in the management of PMBCL, including different chemoimmunotherapy regimens, the use of consolidative radiation therapy, and adaptive approaches based on EOC PET/CT response. These guidelines can be used by practitioners to provide appropriate treatment according to different disease scenarios.

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.

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.

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.

Pediatric mediastinal lymphoma

The mediastinum is the visceral compartment of thoracic cavity divided into the superior and inferior mediastinum, further inferior compartmentalize into anterior, middle, and posterior mediastinum. Lymphoma in the mediastinum may be primary or secondary to systemic disease. Lymphoma may arise from lymphoid organs-like thymus, mediastinal lymph nodes or other mediastinal organs like heart, lung, pleura, and pericardium. It comprises about 12% of all the mediastinal tumors in adults however, it constitutes 50% of the pediatric mediastinal mass. Anatomically lymphoma most commonly involves anterior mediastinum. Among the pediatric mediastinal lymphomas, lymphoblastic lymphoma (LBL) predominate followed by Hodgkin lymphoma (HL), primary mediastinal large B cell lymphoma (PMBCL) and very rarely Grey zone lymphoma. Other types of non-HLs (NHLs) are rare among pediatric population. Radiologically and clinically present as an anterior mediastinal mass with symptoms of dyspnea, cough, and superior vena cava syndrome. Also, clinically and radiologically all the pediatric mediastinal mass shares the overlapping features, hence, for treatment and prognostic points of view its essential to differentiate the three entities, i.e., LBL, HL and PMBCL. The pathological diagnosis of pediatric mediastinal lymphomas is quite challenging for general histopathologists. In this review, we describe the pathology, genetics, differential diagnosis, treatment, prognosis, and a simplified histopathological and immunophenotypical approach to differentiate the pediatric mediastinal lymphomas.

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.

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.

MiRNA Dysregulation in Childhood Hematological Cancer

For decades, cancer biology focused largely on the protein-encoding genes that have clear roles in tumor development or progression: cell-cycle control, apoptotic evasion, genome instability, drug resistance, or signaling pathways that stimulate growth, angiogenesis, or metastasis. MicroRNAs (miRNAs), however, represent one of the more abundant classes of cell modulators in multicellular organisms and largely contribute to regulating gene expression. Many of the ~2500 miRNAs discovered to date in humans regulate vital biological processes, and their aberrant expression results in pathological and malignant outcomes. In this review, we highlight what has been learned about the roles of miRNAs in some of the most common human pediatric leukemias and lymphomas, along with their value as diagnostic/prognostic factors.

Superior vena cava syndrome related to mediastinal lymphoma in late pregnancy: A case report

We report the initial diagnosis in a 28-year-old nulliparous woman of a primary mediastinal B-cell lymphoma in late pregnancy. For several weeks the patient had had symptoms of mediastinal obstruction, such as dyspnea, cough, swelling of the face and upper limbs. However, these symptoms had been misattributed to the pregnancy and a common cold. Due to a rapid decline in the patient's cardiovascular performance, she was transferred to the closest perinatal center in the 34th week of pregnancy, whereupon a cesarean section was performed. The diagnosis of a primary mediastinal B-cell lymphoma was made postpartum from a biopsy. This case emphasizes the importance of timely antenatal investigation in pregnant women with symptoms consistent with mediastinal obstruction. Thoracic ultrasonography can be a valuable tool for the detection of tumor-associated pleural and pericardial effusions.

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The incidence of primary mediastinal B-cell lymphoma (PMBCL) is disproportionately high in women of reproductive age.

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The diagnosis is made at a median age of 35 years.

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Physiological changes during pregnancy can mask mediastinal malignancies since both conditions share similar clinical signs.

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Symptoms of mediastinal obstruction during pregnancy should therefore lead to immediate diagnostic workup.

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Thoracic ultrasound examination can aid in the diagnosis of lymphoma-associated pleural and pericardial effusions.

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.