Role of radiation therapy in primary mediastinal large B-cell lymphoma in rituximab era: A US population-based analysis

Prognostic factors and clinical survival outcome in patients with primary mediastinal diffuse large B-cell lymphoma in rituximab era: A population-based study

The goal of this study was to investigate the clinical characteristics, prognostic variables, and survival of patients with primary mediastinal diffuse large B cell lymphoma (PMBCL) in the rituximab era. The Surveillance, Epidemiology, and End Results (SEER) database was used to identify PMBCL patients diagnosed between 2000 and 2019. The Kaplan-Meier (K-M) technique and log-rank test were used to assess overall survival (OS) and disease-specific survival (DSS). The independent prognostic variables for OS and DSS were identified using univariate and multivariate Cox regression analysis. Nomograms were created to predict survival prospects according to identified prognostic indicators. Totally, 841 patients were enrolled with PMBCL. One-year, 5-year, and 10-year OS rates were 93.99%, 85.04%, and 81.76%, and the corresponding DSS rates were 95.27%, 87.37%, and 85.98%. The results of multivariate Cox regression analysis demonstrated that age, years of diagnosis, Ann arbor staging, and chemotherapy were independent prognostic factors for survival. Nomograms designed exclusively for PMBCL were created to forecast the likelihood of 1-year, 5-year, and 10-year OS and DSS, respectively. The Harrell concordance index (C-index) for the nomograms predictions of OS and DSS were 0.704 and 0.733, respectively, which showed the established model harboring powerful and accurate performance. The present study revealed that incidence of PMBCL has been consistently rising over the last 20 years. Simultaneously, survival rates have improved tremendously. Rituximab based immunochemotherapy has emerged as an effective treatment option, leading to enhanced OS and DSS outcomes. Furthermore, the nomograms specifically developed for PMBCL have demonstrated robustness and accuracy in forecasting OS and DSS rates at 1, 5, and 10 years. These predictive tools can be valuable for clinicians in accurately estimating prognosis and establishing personalized treatment plans and follow-up protocols.

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.

Primary mediastinal/thymic diffuse large B-cell lymphoma: a population-based study on incidence and survival

Primary mediastinal large B-cell lymphoma is a rare subtype of lymphoma. The contemporary incidence of primary mediastinal large B-cell lymphoma remains unknown, and a large population-based study has not been reported. It is essential to provide guidance for further strategies in reducing the disease burden via population-based preventive initiatives. This study aims to explore the epidemiology and effect of therapeutic advances on the survival of patients with primary mediastinal large B-cell lymphoma. This population-based study was conducted using the Surveillance, Epidemiology, and End Results Program (SEER), covering the period from 1975 to 2018. A total of 774 patients in the SEER 9 and 1654 patients in the SEER 18 were analyzed. The age-adjusted incidence rate of primary mediastinal large B-cell lymphoma increased from 0.05/1,000,000 in 1975 to 2.38/1,000,000 in 2018. A significant positive linear increase in the incidence trend was found in primary mediastinal large B-cell lymphoma, with an annual percent change of 8.47% (95% confidence interval 7.7-9.2%, P < 0.001, z test). The survival in primary mediastinal large B-cell lymphoma was significantly superior to nodal diffuse large B-cell lymphoma. The incidence of PMBCL increases over the year. The survival of patients with primary mediastinal large B-cell lymphoma has improved over time.

Primary mediastinal Large B-cell Lymphoma

Primary mediastinal large B-cell lymphoma (PMBCL) is a separate entity in the WHO classification based on clinico-pathologic features and a distinct molecular signature which overlaps with nodular sclerosis classical Hodgkin lymphoma (NScHL). Molecular classifiers can distinguish PMBCL from diffuse large B-cell lymphoma (DLBCL) using RNA derived from paraffin-embedded tissue and are integral to future studies. However, given that ~5% of DLBCL can have a 'molecular' PMBCL phenotype in the absence of mediastinal involvement, clinical information will remain critical for diagnosis. Studies over the last 10-20 years have elucidated the biologic hallmarks of PMBCL which are reminiscent of cHL, including the importance of JAK-STAT and NFKB signaling pathways as well as an immune evasion phenotype through multiple converging genetic aberrations. The outcome of PMBCL has improved in the modern rituximab era, however controversies remain whether there is a single standard treatment for all patients and when to integrate radiotherapy. Regardless of the frontline therapy, refractory disease can occur in up to 10% of patients and correlates with poor outcome. With emerging data supporting high efficacy of PD1 inhibitors in PMBCL, studies are underway integrating them into the up-front setting.

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.

Continuous infusion chemotherapy, radiotherapy, and FDG-PET are feasible during extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) may be used in extreme circumstances for patients with a mediastinal mass and respiratory failure. We report on a young man with primary mediastinal B-cell lymphoma invading into the trachea, requiring a 40-day ECMO run who underwent fluorodeoxyglucose positron emission tomography (FDG-PET) imaging and treatment with concurrent mediastinal irradiation and continuous infusion chemotherapy while on this life-saving technology. This case illustrates that oncology patients may be managed by multidisciplinary teams for extended periods in extraordinary circumstances using multimodality therapies. Additionally, to our knowledge this is the first case to demonstrate the feasibility of FDG-PET imaging while on ECMO.

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.

Spanish Lymphoma Group (GELTAMO) guidelines for the diagnosis, staging, treatment, and follow-up of diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) accounts for approximately 30% of non-Hodgkin lymphoma (NHL) cases in adult series. DLBCL is characterized by marked clinical and biological heterogeneity, encompassing up to 16 distinct clinicopathological entities. While current treatments are effective in 60% to 70% of patients, those who are resistant to treatment continue to die from this disease. An expert panel performed a systematic review of all data on the diagnosis, prognosis, and treatment of DLBCL published in PubMed, EMBASE and MEDLINE up to December 2017. Recommendations were classified in accordance with the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework, and the proposed recommendations incorporated into practical algorithms. Initial discussions between experts began in March 2016, and a final consensus was reached in November 2017. The final document was reviewed by all authors in February 2018 and by the Scientific Committee of the Spanish Lymphoma Group GELTAMO.

Atypical chronic myeloid leukemia: a rare entity with management challenges

The aim of our study was to review the clinicopathologic features and management of atypical chronic myeloid leukemia (aCML). Relevant manuscripts published in English were searched using PubMed. aCML is diagnosed as per WHO 2016 classification in the presence of leukocytosis ≥13 × 109/l with circulating neutrophil precursors ≥10%, monocytes less than 10%, minimal basophils, hypercellular bone marrow with granulocytic proliferation and dysplasia, bone marrow blast less than 20% and absence of BCR/ABL fusion gene. Common cytogenetic features and mutations include trisomy 8, and mutations in SETBP1 and ETNK1. Median survival is 1-2 years. Hematopoietic stem cell transplant may be the only curative option. Ruxolitinib and dasatinib are emerging therapeutic options. Thus, aCML is a rare entity with poor survival. Novel therapies are needed.

Patient characteristics, prognostic factors and outcome of dogs with high-grade primary mediastinal lymphoma

The goals of this retrospective study were to determine the patient characteristics of dogs with high-grade primary mediastinal lymphoma and to determine outcome and associated prognostic factors. A total of 42 dogs were identified, in which 36 received treatment and had follow-up information available. The most common clinical signs included lethargy, anorexia and polyuria/polydipsia. Hypercalcemia and pleural effusion were common findings at diagnosis. The phenotype was almost exclusively T-cell, most often in association with lymphoblastic cytomorphology as defined by the World Health Organization (WHO) lymphoma classification scheme. The overall progression-free survival (PFS) and overall survival (OS) were 133 and 183 days, respectively. Treatment with a CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) protocol was associated with an improved PFS (144 days) and OS (194 days) when compared with dogs that received other medical therapies (P = .005 and P = .002, respectively); the absence of pleural effusion at diagnosis was associated with an increased OS but not PFS. These results suggest that while the prognosis for dogs with mediastinal lymphoma is poor, survival may be improved with treatment using a CHOP-based protocol.

Optimizing Outcomes in Primary Mediastinal B-cell Lymphoma

Primary mediastinal B-cell lymphoma is characterized by a high chance of cure, and cured patients have a long disease-free life-expectancy; however, prognosis is severe in the case of relapsed or refractory disease. The initial use of the most effective chemoimmunotherapy regimen is therefore crucial. Understanding who will benefit from postinduction radiotherapy is also of paramount importance; positron emission tomography may be a reliable guide for physicians in determining which patients will require consolidation. New drugs with mechanisms of action including the most relevant biologic features of the tumor may allow better disease control.

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

The aim of this study is to investigate the incidence and clinical outcomes of primary mediastinal large B-cell lymphoma (PMBL).Here we did a retrospective analysis using the surveillance, epidemiology, and end results (SEER) database to analyze the incidences and survival of patients with PMBL diagnosed during 2001-2012 among major ethnic groups.During 2001-2012, a total of 426 PMBL patients were identified, including 336 whites, 46 blacks, and 44 others. The incidence rates of female to male ratios in white, black, and other were 1.4938, 1.1202, and 1.7303 respectively, suggesting that the female-prominent disease occurrence was seen only in whites and others, but not in black population. Compared to white, the other had a worse 5-year overall survival (OS); however, factors including age, race, socioeconomic status, and stage associated with OS showed no significant difference among ethnic groups; thus, biology factors should be explored to explain the racial difference in OS.In conclusion, our findings revealed diversities in demographic features and prognosis among different racial groups.

Improved survival with combined modality therapy in the modern era for primary mediastinal B-cell lymphoma

Primary mediastinal B-cell lymphoma (PMBCL) is an uncommon lymphoma for which existing data is limited. We utilized the National Cancer Database (NCDB) to evaluate PMBCL and the impact of radiotherapy (RT) on outcomes in the years following FDA approval of rituximab. We queried the NCDB for patients with PMBCL diagnosed from 2006 to 2011 and treated with multiagent chemotherapy. Kaplan-Meier overall survival (OS) estimates, univariate (UVA), and multivariate (MVA) Cox proportional hazards regression analyses were performed. Propensity score matched analysis (PSMA) was performed to account for indication bias and mitigate heterogeneity between treatment groups. 465 patients were identified with a median follow-up of 36 months. Median age was 36 years; 43% received RT. 5-year OS for the entire cohort was 87%, and for the no-RT and RT groups, 83% versus 93%, respectively. On UVA, OS was improved with RT (HR 0.34, P = 0.002). On MVA, RT remained significantly associated with improved OS (HR 0.44, P = 0.028) while Medicaid insurance status and increasing stage remained significantly associated with OS decrement. PSMA confirmed the OS benefit associated with RT. This analysis is the largest PMBCL dataset to date and demonstrates a significant survival benefit associated with RT in patients receiving multiagent chemotherapy in the rituximab era. More than half of patients treated in the United States during this time period did not receive RT. In the absence of phase III data to support omission, combined modality therapy with its associated survival benefit should be the benchmark against which other therapies are compared.

Favorable outcome of primary mediastinal large B-cell lymphoma patients treated with sequential RCHOP-RICE regimen without radiotherapy

PURPOSE

Outcomes in primary mediastinal B cell lymphoma (PMBL) improved with the introduction of dose intense treatments, consolidation radiotherapy and rituximab. DA-EPOCH-R, which omits radiotherapy has been adopted with worldwide enthusiasm, despite lack of proven superiority in randomized trials. We aimed to evaluate the course and outcome of PMBL using an alternative intensive rituximab-containing regimen, RCHOP-RICE. We also evaluated the prognostic value of (18)FDG-PET-CT (PET-CT).

METHODS

We reviewed the clinical, laboratory and imaging data of PMBL patients receiving 1st-line treatment in Hadassah Medical Center between 8/2002 and 10/2014.

RESULTS

Of 47 PMBL patients, 24 (51 %) were treated with RCHOP-RICE and 23 (49 %) with other protocols. Overall, the 5-year progression-free survival was 93 % and the overall survival was 98 % (87 and 100 %, respectively, for the RCHOP-RICE regimen). Patient characteristics and treatment toxicities were balanced among protocols. A mean of 11.1 ± 1.3 hospitalization days/patient were needed to administer RCHOP-RICE regimen compared to 37 ± 2 days/patient for DA-EPOCH-R (n = 2). Radiotherapy was given to 3 patients (12 %) treated with RCHOP-RICE compared to 18 patients (78 %) treated with other protocols (p < 0.01). For patients followed with interim and end of treatment (EOT) PET-CT, we observed a significant reduction in the uptake between the two (p < 0.0001). Using a Deauville score cutoff of 3, the negative and positive predictive values (NPV and PPV) of EOT PET-CT were 94 and 33 %, respectively.

CONCLUSIONS

The RCHOP-RICE protocol results in excellent survival outcomes, generally permits omission of RT and is simpler to administer than DA-EPOCH-R. Interim PET-CT in PMBL may be unjustified; however, EOT Deauville scores ≤3 predicts a favorable outcome.