Fatal anterior mediastinal mass in a pregnant lady.

We report a fatal case of a 26-year-old nulliparous woman who presented with an anterior mediastinal mass in her late pregnancy. She had complained of a progressively increasing neck swelling and occasional dry cough in the early second trimester, which was associated with worsening dyspnoea, reduced effort tolerance and orthopnoea. Ultrasound of the neck showed an enlarged lymph node, and chest X-ray revealed mediastinal widening. At 35 weeks' gestation, the patient was referred to a tertiary centre for a computed tomography (CT) scan of the neck and thorax under elective intubation via awake fibreoptic nasal intubation as she was unable to lie flat. However, she developed sudden bradycardia, hypotension and desaturation soon after being positioned supine, which required resuscitation. She succumbed after 3 days in the intensive care unit. An autopsy revealed a large anterior mediastinal mass extending to the right supraclavicular region, displacing the heart and lungs, encircling the superior vena cava and right internal jugular vein with tumour thrombus extending into the right atrium. Histopathology examination of the mediastinal mass confirmed the diagnosis of a primary mediastinal large B-cell lymphoma. This report emphasizes the severe and fatal outcome resulting from the delay and misinterpretation of symptoms related to a mediastinal mass.

Exploring the cell-free total RNA transcriptome in diffuse large B-cell lymphoma and primary mediastinal B-cell lymphoma patients as biomarker source in blood plasma liquid biopsies.

Introduction: Diffuse large B-cell lymphoma (DLBCL) and primary mediastinal B-cell lymphoma (PMBCL) are aggressive histological subtypes of non-Hodgkin's lymphoma. Improved understanding of the underlying molecular pathogenesis has led to new classification and risk stratification tools, including the development of cell-free biomarkers through liquid biopsies. The goal of this study was to investigate cell-free RNA (cfRNA) biomarkers in DLBCL and PMBCL patients. Materials and methods: Blood plasma samples (n=168) and matched diagnostic formalin-fixed paraffin-embedded (FFPE) tissue samples (n=69) of DLBCL patients, PMBCL patients and healthy controls were collected between 2016-2021. Plasma samples were collected at diagnosis, at interim evaluation, after treatment, and in case of refractory or relapsed disease. RNA was extracted from 200 µl plasma using the miRNeasy serum/plasma kit and from FFPE tissue using the miRNeasy FFPE kit. RNA was subsequently sequenced on a NovaSeq 6000 instrument using the SMARTer Stranded Total RNA-seq pico v3 library preparation kit. Results: Higher cfRNA concentrations were demonstrated in lymphoma patients compared to healthy controls. A large number of differentially abundant genes were identified between the cell-free transcriptomes of DLBCL patients, PMBCL patients, and healthy controls. Overlap analyses with matched FFPE samples showed that blood plasma has a unique transcriptomic profile that significantly differs from that of the tumor tissue. As a good concordance between tissue-derived gene expression and the immunohistochemistry Hans algorithm for cell-of-origin (COO) classification was demonstrated in the FFPE samples, but not in the plasma samples, a 64-gene cfRNA classifier was developed that can accurately determine COO in plasma. High plasma levels of a 9-gene signature (BECN1, PRKCB, COPA, TSC22D3, MAP2K3, UQCRHL, PTMAP4, EHD1, NAP1L1 pseudogene) and a 5-gene signature (FTH1P7, PTMAP4, ATF4, FTH1P8, ARMC7) were significantly associated with inferior progression-free and overall survival in DLBCL patients, respectively, independent of the NCCN-IPI score. Conclusion: Total RNA sequencing of blood plasma samples allows the analysis of the cell-free transcriptome in DLBCL and PMBCL patients and demonstrates its unexplored potential in identifying diagnostic, cell-of-origin, and prognostic cfRNA biomarkers.

Mature B-cell lymphomas in adolescents and young adults.

Pediatric non-Hodgkin lymphoma includes over 30 histologies (many with subtypes), with approximately 800 cases per year in the US, compared to >60,000 cases of adult NHL annually. Improvements in survival in pediatric and adolescent mature B cell NHL over the past 5 decades align with the overall success of the cooperative trial model with dramatic improvements in outcomes through dose escalation of chemotherapy and, more recently, targeted therapy with rituximab. Pediatric dose-intense strategies carry risks of long-term consequences, but treatment failure is nearly universally fatal. By comparison, adult mature B cell lymphoma is typically less aggressive and treated with less intense chemotherapy. Optimizing therapy for adolescents and young adults remains a major challenge that requires creative solutions, including engineering study groups to combine biologically comparable adult and pediatric populations and developing effective salvage strategies that will ultimately be required for investigations of front-line dose reduction. In this review, we discuss challenges and opportunities for improving outcomes for adolescents and young adults with high-grade mature B cell lymphomas, diffuse large B cell lymphoma, and primary mediastinal B cell lymphoma.

Case Report: Severe cutaneous adverse event associated with checkpoint inhibition in the setting of CAR T-cell therapy: beyond CRS.

Anti-CD19 chimeric antigen receptor (CAR) T cell therapy actually represents the standard of care for multiple relapsed or refractory primary mediastinal B-cell lymphoma (r/r PMBCL). Checkpoint inhibitors, such as pembrolizumab, appear to be a safe and effective treatment strategy for patients who are ineligible for or resistant to autologous stem cell transplantation. Although preclinical studies suggested that checkpoint inhibitors may enhance the vitality and anti-tumor activity of CAR T cells, there are no substantial/robust clinical data about the immune-mediated toxicity of their association. We describe a case of a severe cutaneous adverse event arising immediately after Cytokine Release Syndrome (CRS) on day +6 from CAR T cells infusion in a young r/r PMBCL patient who previously received pembrolizumab. These skin lesions were interpreted as an immune mediated adverse event, considering their prompt improvement and fully recovering achieved with the addition of immunoglobulin infusion to systemic steroid therapy. This case of life-threatening cutaneous adverse event calls for further investigations about off-target immune-related adverse events deriving from the combination of CAR T cell therapy and checkpoint inhibition, whose synergic therapeutic effect is promising.

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.

Neuropsychiatric disorders in adults undergoing chimeric antigen receptor T cells therapy for aggressive lymphomas and acute lymphoblastic leukemia.

Objective: To evaluate risk factors for neuropsychiatric disorders (NPD) in recipients of CART therapy. Methods: Patients ≥ 18 years with acute lymphoblastic leukemia (ALL), and aggressive B-cell lymphomas who received CART in 2018 were evaluated. Patients with and without NPD were compared. Results: NPD was diagnosed in 31.2% of patients. Compared to patients without NPD, patients with NPD were likely to be females (P = 0.035) and have ALL (P = 0.039). NPD was significantly associated with female gender (OR = 2.03) and diagnosis of ALL (OR = 2.76). No association between NPD and outcomes. Conclusions: Female gender and ALL were risk factors for NPD.

Case Report: Primary Mediastinal Large B-Cell Lymphoma Invasion of Extranodal Thyroid Tissue Mimicking Tuberculosis and Confounded by Similar Ultrasonic Appearance.

Background: Primary mediastinal large B-cell lymphoma (PMBCL) is a rare type of diffuse large B-cell lymphoma, which has significant features that overlap with those of Hodgkin's lymphoma. Ultrasound is a commonly used modality to characterize superficial lymph no5des, and ultrasonic findings are often used to distinguish lymphoma from lymph node tuberculosis in daily clinical practice. Although a common malignancy, lymphoma rarely involves extranodal tissues. Case Presentation: Here we report the case of a 42-year-old Chinese male patient with PMBCL who was misdiagnosed with tuberculosis because of extranodal invasion. He visited our hospital for a neck mass that he had been noting for 1 week. Ultrasound revealed multiple enlarged lymph nodes on both sides of the neck. The lesions appeared to involve the surrounding soft tissue and thyroid gland, resembling a tuberculous sinus tract formation. Cervical spine computed tomography showed no obvious abnormalities in the cervical cone or bone damage. Contrast-enhanced ultrasound indicated that one of the enlarged lymph nodes in the right neck was rich in blood supply and exhibited centripetal enhancement, with uniform high enhancement at the peak. The patient underwent two ultrasound-guided punctures; the first puncture was performed for an enlarged lymph node in the right neck at Hangzhou Red Cross Hospital. Hodgkin's lymphoma was suspected based on pathological and immunohistochemical findings, whereas a rare type of diffuse large B-cell lymphoma was suspected at Zhejiang Cancer Hospital. Conclusions: Lymphoma is often misdiagnosed, causing delayed treatment initiation and affecting patient outcomes as the disease progresses. The present case demonstrates that the ultrasonic appearance of lymphoma may sometimes be confused with that of tuberculosis. Although ultrasound-guided needle biopsy has a high diagnostic accuracy, it may also cause diagnostic deviation because of insufficient sampling volume. Moreover, owing to the enlargement of multiple lymph nodes due to lymphoma or lymph node tuberculosis, puncturing different lymph nodes may provide different results.

STR Profiling Reveals Tumor Genome Instability in Primary Mediastinal B-Cell Lymphoma.

Primary mediastinal B-cell lymphoma (PMBCL) is the only non-Hodgkin's lymphoma variant responding to immune checkpoint inhibitor (ICI) therapy, approximately in half of the cases; however, no molecular markers predicting a response to ICI therapy in PMBCL have been described so far. In this study, we assessed the incidence of the loss of heterozygosity (LOH), elevated microsatellite alteration at selected tetranucleotides (EMAST), and microsatellite instability (MSI) in the tumor genomes of 72 patients with PMBCL undergoing high-dose chemotherapy treatment at the National Research Center for Hematology (Moscow, Russia). Tumor DNA was isolated from biopsy samples taken at diagnosis. Control DNA was isolated from the blood of patients in complete remission or from buccal epithelium. STR-profiles for LOH and EMAST were assessed by PCR with COrDIS Plus multiplex kit (Gordiz Ltd., Moscow, Russia). LOH was detected in 37 of 72 patients (51.4%). EMAST was found in 40 patients (55.5%); 24 had a combination of EMAST with LOH. MSI-high was not found, while MSI-low was detected only in one patient. The association of certain genetic lesions with the clinical outcome in patients receiving treatment according to the standard clinical protocol R-Da-EPOCH-21 has been estimated (58 patients out of 72) and no associations with the worst overall or event-free survival were found.

Dose-adjusted EPOCH-R is not superior to sequential R-CHOP/R-ICE as a frontline treatment for newly diagnosed primary mediastinal B-cell lymphoma: Results of a bi-center retrospective study.

PURPOSE: Primary mediastinal B-cell lymphoma (PMBCL) is a rare subtype of diffuse large B-cell lymphoma (DLBCL). Despite its aggressive course, PMBCL is considered curable. While in recent years dose-adjusted (DA) EPOCH-R (rituximab, etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin) has become widely endorsed as first-line therapy for newly-diagnosed PMBCL, the optimal treatment for this disease and the role of radiotherapy (RT) remains unclear. DA-EPOCH-R provides good clinical outcomes, albeit is associated with short- and long-term toxicity. To address this issue, the current retrospective bi-icenter analysis compared efficacy and toxicity of DA-EPOCH-R and a less toxic R-CHOP/R-ICE regimen used for the treatment of newly-diagnosed PMBCL. PATIENTS AND METHODS: The study included all patients with a histologically confirmed PMBCL diagnosis treated with DA-EPOCH-R or R-CHOP/R-ICE between 01/2013-12/2020 at two tertiary medical centers. Patient demographic and clinical data were derived from institutional electronic medical records. The analysis included 56 patients: 31 received DA-EPOCH-R and 25 - R-CHOP/R-ICE. RESULTS: At a median follow-up of 1.9 years (IQR 3.1 years), similar progression-free survival (2.1 versus 2.4 years; p = 0.7667), overall survival (2.5 versus 2.7 years; p = 0.8047) and complete response (80%) were observed in both groups. However, DA-EPOCH-R was associated with significantly longer hospitalization required for its administration (p < 0.001) and a trend for higher frequency of infections, stomatitis, thrombotic complications and febrile neutropenia-related hospitalizations. CONCLUSION: DA-EPOCH-R and R-CHOP/R-ICE provide similarly encouraging outcomes in newly-diagnosed PMBCL patients. R-CHOP/R-ICE is associated with lower toxicity and significantly reduced hospitalization. Our findings suggest that this regimen may be considered as an alternative to DA-EPOCH-R in this patient population.

Salvage Therapy With Polatuzumab Vedotin, Bendamustine, and Rituximab Prior to Allogeneic Hematopoietic Transplantation in Patients With Aggressive Lymphomas Relapsing After Therapy With Chimeric Antigen Receptor T-Cells-Report on Two Cases.

Up to 60% of patients with aggressive B-cell lymphoma who receive chimeric antigen receptor (CAR) T-cell therapy experience treatment failure and subsequently have a poor prognosis. Allogeneic hematopoietic stem cell transplantation (alloHSCT) remains a potentially curative approach for patients in this situation. Induction of a deep response prior to alloHSCT is crucial for long-term outcomes, but the optimal bridging strategy following relapse after CAR T-cell therapy has not yet been established. Polatuzumab vedotin, an antibody drug conjugate targeting CD79b, is a novel treatment option for use in combination with rituximab and bendamustine (Pola-BR) in relapsed or refractory disease. Patients: We report two heavily pretreated patients with primary refractory diffuse large B-cell lymphoma (DLBCL) and primary mediastinal B-cell lymphoma (PMBCL) respectively who relapsed after therapy with CAR T-cells with both nodal and extranodal manifestations of the disease. After application of three courses of Pola-BR both patients achieved a complete metabolic remission. Both patients underwent alloHSCT from a human leukocyte antigen (HLA)-mismatched donor following conditioning with busulfan and fludarabine and are disease free 362 days and 195 days after alloHSCT respectively. We conclude that Pola-BR can be an effective bridging therapy before alloHSCT of patients relapsing after CAR T-cell therapy. Further studies will be necessary to define the depth and durability of remission of this salvage regimen before alloHSCT.

Current and emerging treatment options in primary mediastinal B-cell lymphoma.

Previously considered a subtype of diffuse large B-cell lymphoma (DLBCL), primary mediastinal B-cell lymphoma (PMBCL) is now recognized by the World Health Organization as an independent entity. PMBCL has clinicopathologic features that are separate from systemic DLBCL and harbors some biologic characteristics which overlap with nodular sclerosing classic Hodgkin's lymphoma (cHL). Similar to cHL, copy number alterations of 9p24.1 are frequently seen in PMBCL, which leads to increased expression of key genes in the region, including programmed death-ligand 1( PD-L1), PD-L2, and JAK2. In addition, PMBCL cells express CD30 in a mostly patchy fashion. In the upfront setting, dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab (i.e., DA-EPOCH-R) is the only regimen that has been shown in a prospective setting to result in outstanding outcomes without consolidative radiation to the mediastinum, with a 5-year event-free survival rate of 93% and overall survival rate of 97%. Thus, in recent years, DA-EPOCH-R has been recognized as the preferred frontline regimen. Despite the encouraging results in the frontline setting, the outcomes in the relapsed/refractory setting remain poor. The current approach of salvage chemotherapy followed by autologous stem cell transplantation, as used in patients with DLBCL, does not result in high rates of cure in patients with rrPMBCL. In recent years, the characteristic molecular features identified in PMBCL have provided more treatment opportunities for this patient population. In the relapsed setting, single-agent PD-1 inhibitor pembrolizumab have demonstrated high and durable remission rates. Despite the expression of CD30, the CD30 antibody drug-conjugate brentuximab vedotin (BV) as a single agent has been deemed inactive in this disease. On the contrary, the combinations of BV and PD-1 inhibitor have shown higher response rates than PD-1 inhibitor alone. Moreover, anti-CD19 chimeric antigen receptor T-cell (CAR T-cell) therapy has been positioned as another successful strategy for patients with rrPMBCL. Axicabtagene ciloleucel and lisocabtagene maraleucel are two products used in rrPMBCL.

Chemotherapy During Active SARS-CoV2 Infection: A Case Report and Review of the Literature.

COVID-19 has become the biggest public health problem and one of the most important causes of death in many countries in the world. SARS-CoV-2 infection is most likely to be fatal in elderly patients with concomitant diseases. In this article we present two cases of asymptomatic SARS-CoV-2-positive patients suffering from cancer who were treated with chemotherapy. The first case, a patient with primary mediastinal B-cell lymphoma, shows that confirmed SARS-CoV-2 infection does not have to be a contraindication to chemotherapy. We describe the course of disease and discuss doubts related to the choice of chemotherapy regimen. The second patient was a male with metastatic sigmoid cancer treated with FOLFOX4 as first-line palliative chemotherapy. This case draws attention to asymptomatic SARS-CoV-2 carriers who underwent chemotherapy. Our patient was safely treated with chemotherapy without long break caused by viral infection. It should be remembered that there are asymptomatic carriers among cancer patients and that they may spread infection to others. On the other hand, delaying chemotherapy can cause rapid disease progression and reduce overall survival of our patients.

Concurrent application of blinatumomab and haploidentical donor leukocyte infusions for refractory primary mediastinal large B-cell lymphoma.

Primary mediastinal large B-cell lymphoma (PMBCL) is a rare hematologic malignancy with distinct clinical and immunopathological features. We report a case of a young male with disease refractory to multiple lines of therapy, including chimeric antigen receptor-T cells, who achieved his first complete remission after haploidentical bone marrow transplantation (haplo-BMT), following donor leukocyte infusions (DLIs) given concurrently with blinatumomab. While DLI has been used after T-replete haplo-BMT with post-transplant cyclophosphamide, there are no reports on its use for PMBCL. Similarly, blinatumomab is active against B-cell lymphomas, but literature is lacking in patients with PMBCL. Our experience illustrates that blinatumomab can be used concurrently with DLI in a haploidentical setting to achieve disease response in PMBCL. Despite our encouraging experience with this case, we would not recommend this approach outside of a clinical trial as blinatumomab may exacerbate the graft versus host disease risks of DLI, especially in a haploidentical setting. Evaluating this treatment combination in high-risk patients in the setting of a clinical trial may be meaningful.

Primary Mediastinal (Thymic) Large B-Cell Lymphoma: Fidelity of Diagnosis Using WHO Criteria.

PURPOSE: Diagnosing primary mediastinal (thymic) large B-cell lymphoma (PMBCL) is challenging because it is a clinicopathologic entity that shares characteristics with other lymphomas and lacks pathognomonic features. We sought to investigate the fidelity between a working diagnosis of PMBCL at our institution and the clinicopathologic criteria established within the 2017 World Health Organization (WHO) classification. PATIENTS AND METHODS: Medical records and archived tissue of patients treated for stage I-II PMBCL from 1998 to 2018 were retrospectively reviewed for clinical and pathologic conformity with current WHO criteria. Disease was characterized as definitely PMBCL if all of the following were present: anterior mediastinal mass with or without lymph node involvement, no extranodal disease, B-cell antigen expression, Epstein-Barr virus negativity, and at least one supportive feature: female gender under age 40, bulky primary tumor, CD30 weakly positive, compartmentalizing alveolar fibrosis, lack of surface immunoglobulin expression, and MUM1 or CD23 positivity. Disease without supportive features or other pathologic findings more suggestive of other entities was characterized as equivocal for PMBCL. Lack of an anterior mediastinal mass, presence of distant lymph node involvement or extranodal disease, lack of B-cell antigen expression, or Epstein-Barr virus positivity were characterized as definitely not PMBCL. Clinical management and outcomes were also assessed. RESULTS: Of 63 patients treated for presumed stage I-II PMBCL, 58 (92%) met the criteria for PMBCL. The most common reason for a discordant diagnosis was lack of an anterior mediastinal mass (n = 3). Two additional patients were characterized as having disease equivocal for PMBCL. In retrospect, one patient most likely had a mediastinal gray zone lymphoma due to CD15 positivity and another diffuse large B cell, not otherwise specified, at pathologic review. Five-year progression-free and overall survival were 67% (95% confidence interval, 54-77) and 81% (95% confidence interval, 68-89), respectively, for all patients. CONCLUSION: Despite the complexity of the clinicopathologic criteria of PMBCL, most patients (92%) who were treated for stage I-II PMBCL at our institution appear to have been accurately diagnosed.

Excellent survival after R-Hyper-CVAD in hospitalized patients with high-risk large B-cell lymphoma: The Karolinska experience.

Patients with high-risk aggressive B-cell lymphoma exhibit poor survival after R-CHOP. More intensive regimens yield higher rates of remission but also of complication. We investigated all 401 patients < 70 years with high-risk (age-adjusted [aa] international prognostic index [IPI] ≥2, extranodal, or bulky) aggressive B-cell lymphoma hospitalized at Karolinska for urgent start of immunochemotherapy (129 R-Hyper-CVAD; 261 R-CHOP/R-CHOEP). Patients showed IPI 3-5 (70%), WHO PS ≥2 (49%), bulky disease (70%), extranodal (75%) and CNS (8%) involvement. Five-year overall/progression-free survival (OS/PFS) was better in patients who started R-Hyper-CVAD (84%/77%) compared with R-CHOP/R-CHOEP (66%/55%). Differences were independent in multivariable analysis, seen in all patient categories, and accentuated in extreme high-risk disease: R-Hyper-CVAD vs. R-CHOP/R-CHOEP showed 5-year PFS 69% vs.40% in aaIPI 3 and 88% vs. 38% in CNS involvement. For validation, survival was compared between the two Karolinska sites and calendar periods. Survival was superior 2006-2010 at the site that introduced R-Hyper-CVAD/R-MA 2006, identical at both sites 2011-2017 after the other site adopted R-Hyper-CVAD/R-MA 2011, and excellent 2018-2020 when R-Hyper-CVAD/R-MA use increased to 75% of patients. Despite considerable toxicity, also patients aged 61-69 years showed better survival with R-Hyper-CVAD/R-MA. This is the largest single-centre series of patients treated with R-Hyper-CVAD/R-MA, showing favourable outcome in high-risk aggressive B-cell lymphoma.

Relapsed/refractory primary mediastinal large B-cell lymphoma: a structured review of epidemiology, treatment guidelines and real-world treatment practices.

Background: Primary mediastinal (thymic) large B-cell lymphoma (PMBCL) is an uncommon subtype of diffuse large B-cell lymphoma. Approximately 10-30% of patients experience refractory or relapsed PMBCL (rrPMBCL) after first-line therapy. Data and treatment guidelines for rrPMBCL are scarce, and management is based on clinical experience.Methods: Two structured literature reviews were undertaken to determine the incidence, prevalence, and mortality rates associated with rrPMBCL, and to identify clinical practice guidelines and real-world patterns of care.Results: Epidemiology studies included reported lymphomas (n = 1), non-Hodgkin lymphoma (n = 1), lymphoid neoplasm (n = 1), PMBCL (n = 6), and rrPMBCL (n = 1). Of 12 published treatment guidelines, only four provided recommendations for rrPMBCL. Sixteen studies provided data on real-world treatment patterns, but most were single-center studies with small patient numbers. Chemotherapy/immunochemotherapy, followed by high-dose treatment (HDT) and stem cell transplantation, was a mainstay of salvage therapy in most studies; real-world care generally followed treatment guidelines.Conclusions: Salvage chemotherapy (often with rituximab and radiotherapy), followed by HDT and stem cell transplantation, appears to be the standard real-world treatment for rrPMBCL. However, large prospective and retrospective studies are warranted to improve our knowledge of real-world treatment patterns.

The Unsolved Puzzle of c-Rel in B Cell Lymphoma.

Aberrant constitutive activation of Rel/NF-κB transcription factors is a hallmark of numerous cancers. Of the five Rel family members, c-Rel has the strongest direct links to tumorigenesis. c-Rel is the only member that can malignantly transform lymphoid cells in vitro. Furthermore, c-Rel is implicated in human B cell lymphoma through the frequent occurrence of REL gene locus gains and amplifications. In normal physiology, high c-Rel expression predominates in the hematopoietic lineage and a diverse range of stimuli can trigger enhanced expression and activation of c-Rel. Both expression and activation of c-Rel are tightly regulated on multiple levels, indicating the necessity to keep its functions under control. In this review we meta-analyze and integrate studies reporting gene locus aberrations to provide an overview on the frequency of REL gains in human B cell lymphoma subtypes, namely follicular lymphoma, diffuse large B cell lymphoma, primary mediastinal B cell lymphoma, and classical Hodgkin lymphoma. We also summarize current knowledge on c-Rel expression and protein localization in these human B cell lymphomas and discuss the co-amplification of BCL11A with REL. In addition, we highlight and illustrate key pathways of c-Rel activation and regulation with a specific focus on B cell biology.

Application of PD-1 Blockade in Cancer Immunotherapy.

The programmed cell death protein 1 (PD-1) pathway has received considerable attention due to its role in eliciting the immune checkpoint response of T cells, resulting in tumor cells capable of evading immune surveillance and being highly refractory to conventional chemotherapy. Application of anti-PD-1/PD-L1 antibodies as checkpoint inhibitors is rapidly becoming a promising therapeutic approach in treating tumors, and some of them have successfully been commercialized in the past few years. However, not all patients show complete responses and adverse events have been noted, suggesting a better understanding of PD-1 pathway mediated immunosuppression is needed to predict patient response and improve treatment efficacy. Here, we review the progresses on the studies of the mechanistic role of PD-1 pathway in the tumor immune evasion, recent clinical development and commercialization of PD-1 pathway inhibitors, the toxicities associated with PD-1 blockade observed in clinical trials as well as how to improve therapeutic efficacy and safety of cancer immunotherapy.

Mediastinal Lymphoma Presenting in Cardiogenic Shock with Superior Vena Cava Syndrome in a Primigravida at Full Term: Salvage Resection after Prolonged Extracorporeal Life Support.

Primary mediastinal large B-cell lymphoma (PMBCL) is a rare type of non-Hodgkin lymphoma that typically has a good response rate to first line chemotherapy regimens. There have been reports of successful chemotherapy, but with a residual mass from fibrosis. Here, we report the case of a 19-year-old primigravida presenting with cardiogenic shock and superior vena cava (SVC) syndrome at full term who was found to have a PMBCL. Following delivery via urgent cesarean section, she was put on veno-arterial extra corporeal membrane oxygenation (VA-ECMO) and once hemodynamically stable was started on chemotherapy. In view of limited change in tumor size on consecutive CT scans and questionable response to chemotherapy, there were multidisciplinary meetings wherein withdrawing support was discussed and put forward to the family. At that point, surgical debulking was offered on compassionate grounds to be able to wean her off the VA-ECMO. This case report highlights the role of salvage resection when there are no other options.