Primary mediastinal B-cell lymphoma and mediastinal gray zone lymphoma: do they require a unique therapeutic approach?

What is new in the 5th edition of the World Health Organization classification of mature B and T/NK cell tumors and stromal neoplasms?

The classification of tumors is essential in the diagnosis and clinical management of patients with malignant neoplasms. The World Health Organization (WHO) provides a globally applicable classification scheme of neoplasms and it was updated several times. In this review, we briefly outline the cornerstones of the upcoming 5th edition of the World Health Organization Classification of Haematolymphoid Tumours on lymphoid neoplasms. As is adopted throughout the 5th edition of the WHO classification of tumors of all organ systems, entities are listed by a hierarchical system. For the first time, tumor-like lesions have been included in the classification, and modifications of nomenclature for some entities, revisions of diagnostic criteria or subtypes, deletion of certain entities, and introduction of new entities are presented along with mesenchymal lesions specific to the stroma of lymph nodes and the spleen. In addition to specific outlines on constitutional and somatic genetic changes associated with given entities, a separate chapter on germline predisposition syndromes related to hematologic neoplasms has been added.

A first-in-class inhibitor of HSP110 to potentiate XPO1-targeted therapy in primary mediastinal B-cell lymphoma and classical Hodgkin lymphoma

BACKGROUND

Primary mediastinal B-cell lymphoma (PMBL) and classical Hodgkin lymphoma (cHL) are distinct hematological malignancies of B-cell origin that share many biological, molecular, and clinical characteristics. In particular, the JAK/STAT signaling pathway is a driver of tumor development due to multiple recurrent mutations, particularly in STAT6. Furthermore, the XPO1 gene that encodes exportin 1 (XPO1) shows a frequent point mutation (E571K) resulting in an altered export of hundreds of cargo proteins, which may impact the success of future therapies in PMBL and cHL. Therefore, targeted therapies have been envisioned for these signaling pathways and mutations.

METHODS

To identify novel molecular targets that could overcome the treatment resistance that occurs in PMBL and cHL patients, we have explored the efficacy of a first-in-class HSP110 inhibitor (iHSP110-33) alone and in combination with selinexor, a XPO1 specific inhibitor, both in vitro and in vivo.

RESULTS

We show that iHSP110-33 decreased the survival of several PMBL and cHL cell lines and the size of tumor xenografts. We demonstrate that HSP110 is a cargo of XPO1wt as well as of XPO1E571K. Using immunoprecipitation, proximity ligation, thermophoresis and kinase assays, we showed that HSP110 directly interacts with STAT6 and favors its phosphorylation. The combination of iHSP110-33 and selinexor induces a synergistic reduction of STAT6 phosphorylation and of lymphoma cell growth in vitro and in vivo. In biopsies from PMBL patients, we show a correlation between HSP110 and STAT6 phosphorylation levels.

CONCLUSIONS

These findings suggest that HSP110 could be proposed as a novel target in PMBL and cHL therapy.

Modulating Cholesterol Metabolism via ACAT1 Knockdown Enhances Anti-B-Cell Lymphoma Activities of CD19-Specific Chimeric Antigen Receptor T Cells by Improving the Cell Activation and Proliferation

CD19-specific CAR-T immunotherapy has been extensively studied for the treatment of B-cell lymphoma. Recently, cholesterol metabolism has emerged as a modulator of T lymphocyte function and can be exploited in immunotherapy to increase the efficacy of CAR-based systems. Acetyl-CoA acetyltransferase 1 (ACAT1) is the major cholesterol esterification enzyme. ACAT1 inhibitors previously shown to modulate cardiovascular diseases are now being implicated in immunotherapy. In the present study, we achieved knockdown of ACAT1 in T cells via RNA interference technology by inserting ACAT1-shRNA into anti-CD19-CAR-T cells. Knockdown of ACAT1 led to an increased cytotoxic capacity of the anti-CD19-CAR-T cells. In addition, more CD69, IFN-γ, and GzmB were expressed in the anti-CD19-CAR-T cells. Cell proliferation was also enhanced in both antigen-independent and antigen-dependent manners. Degranulation was also improved as evidenced by an increased level of CD107a. Moreover, the knockdown of ACAT1 led to better anti-tumor efficacy of anti-CD19 CAR-T cells in the B-cell lymphoma mice model. Our study demonstrates novel CAR-T cells containing ACAT1 shRNA with improved efficacy compared to conventional anti-CD19-CAR-T cells in vitro and in vivo.

Brentuximab vedotin as a bridge to combination chemotherapy in gray zone lymphoma with severe liver impairment: a case report

Background

Gray zone lymphoma (GZL) is a rare lymphoma subtype characterized by features intermediate between diffuse large B-cell lymphoma (DLBCL) and classic Hodgkin lymphoma (cHL). The optimal first-line treatment for GZL remains undefined, particularly for patients with poor performance status or baseline organ impairment. Brentuximab vedotin (BV), a targeted therapy that binds to CD30, a TNFR superfamily member involved in NF-kB signaling, has shown promise in the treatment of CD30-positive lymphomas. However, its use in GZL, especially in patients with severe liver impairment, has not been reported previously.

Case description

We present a case of a 37-year-old male with GZL and severe liver impairment at initial presentation. The patient initially received monotherapy with BV, which resulted in a marked improvement in liver enzymes and bilirubin levels. Subsequently, combination cytotoxic chemotherapy consisting of dose-adjusted etoposide, prednisone, cyclophosphamide, and doxorubicin (DA-EP_CH) was added. Repeat imaging revealed near complete resolution of lymphadenopathy and significant reduction in hepatosplenomegaly. The patient completed a full course of chemotherapy and achieved a complete response. Follow-up examinations showed no evidence of recurrent disease, and the patient resumed full-time work.

Discussion

GZL poses diagnostic challenges due to its overlapping features with DLBCL and cHL. Accurate diagnosis relies on comprehensive histopathological evaluation, immunophenotyping, and molecular analysis. The optimal first-line treatment for GZL remains uncertain. BV shows promise as an addition to chemotherapy in GZL, even in the presence of severe liver impairment. The molecular pathogenesis of GZL is complex and heterogeneous, frequently involving aberrant NF-kB signaling and impaired apoptosis regulation via loss of TP53 expression. Understanding the underlying molecular mechanisms is essential for developing targeted therapies and identifying predictive biomarkers for treatment response.

Conclusion

This case demonstrates the successful use of BV as a bridge to cytotoxic chemotherapy in a GZL patient with severe liver impairment, highlighting its potential safety and efficacy even in the setting of end-organ failure. Further investigation is warranted to define optimal treatment strategies, identify predictive biomarkers, and improve outcomes for patients with this rare and challenging lymphoma subtype.

Cost-effectiveness of axicabtagene ciloleucel versus tisagenlecleucel for the treatment of 3L + relapsed/refractory large B-cell lymphoma in the United States: incorporating longer survival results

AIMS

To provide an update on the cost-effectiveness of the chimeric antigen receptor (CAR) T-cell therapies axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) for the treatment of relapsed/refractory (r/r) large B-cell lymphoma (LBCL) among patients who have previously received ≥2 lines of systemic therapy using more mature clinical trial data cuts (60 months for axi-cel overall survival [OS] and 45 months for tisa-cel OS and progression-free survival [PFS]).

METHODS

A partitioned survival model consisting of three health states (pre-progression, post-progression and death) was used to estimate quality-adjusted life years (QALYs) and costs associated with axi-cel and tisa-cel over a lifetime horizon. PFS and OS inputs for axi-cel and tisa-cel were based on a previously published matching-adjusted indirect treatment comparison (MAIC). Long-term OS and PFS were extrapolated using parametric survival mixture cure models (PS-MCMs). Costs of CAR-T cell therapy drug acquisition and administration, conditioning chemotherapy, apheresis, CAR T-specific monitoring, stem cell transplant, hospitalization, adverse events, routine care, and terminal care were sourced from US cost databases. Health state utilities were derived from previous publications. Model inputs were varied using a range of sensitivity and scenario analyses.

RESULTS

Compared with tisa-cel, axi-cel resulted in 2.51 additional QALYs and $50,185 additional costs (an incremental cost-effectiveness ratio [ICER] of $19,994 per QALY gained). In probabilistic sensitivity analysis (PSA), the ICER for axi-cel versus tisa-cel was ≤$50,000/QALY in 99.4% of simulations and ≤$33,500 in 99% of simulations. Axi-cel remained cost-effective versus tisa-cel (assuming a willingness-to-pay threshold of $150,000 per QALY) across a range of scenarios.

CONCLUSIONS

With longer-term survival data, axi-cel continues to represent a cost-effective option versus tisa-cel for treatment of r/r LBCL among patients who have previously received ≥2 lines of systemic therapy, from a US payer perspective.

Mediastinal large B cell lymphoma and surrounding gray areas: a report of the lymphoma workshop of the 20th meeting of the European Association for Haematopathology

Session 3 of the 2021 European Association for Haematopathology/Society for Hematopathology Workshop focused on mediastinal large B cell lymphomas and surrounding gray areas. One half of the session was dedicated to primary mediastinal large B cell lymphoma (PMBL) and included cases with classic clinicopathologic features, as well as cases with either morphologic or immunophenotypic variation, and PMBL-like cases with primary extramediastinal disease. The role of additional immunophenotyping and/or molecular testing to aid in the diagnosis of PMBL was discussed. The second half of the session focused on mediastinal and non-mediastinal gray zone lymphomas (GZL) with features intermediate between diffuse large B cell lymphoma (DLBCL) and classic Hodgkin lymphoma (CHL). Several cases illustrating the current challenges in separating this entity from PMBL/DLBCL and CHL were presented. There was discussion regarding the clinical and genetic differences between mediastinal and non-mediastinal GZLs. Rare cases of PMBL and GZL associated with EBV or follicular lymphoma were reviewed. Finally, several cases included in the session highlighted composite or sequential CHL and PMBL/DLBCL and/or GZL, highlighting challenges in separating such cases from GZL.

Aggressive non-Hodgkin lymphoma in the pediatric and young adult population; diagnostic and molecular pearls of wisdom

Mature non-Hodgkin lymphomas (NHLs) of the pediatric and young adults(PYA), including Burkitt lymphoma (BL), diffuse large B cell lymphoma (DLBCL), high-grade B cell lymphoma (HGBCL), primary mediastinal large B cell lymphoma (PMBL) and anaplastic large cell lymphoma (ALCL), generally have excellent prognosis compared to the adult population. BL, DLBCL and HGBCL are usually of germinal center (GCB) origin in the PYA population. PMBL neither belongs to the GCB nor the activated B cell subtype and is associated with a poorer outcome than BL or DLBCL of comparable stage. Anaplastic large cell lymphoma is the most frequent peripheral T cell lymphoma occurring in the PYA and accounts for 10-15% of childhood NHL. Most pediatric ALCL, unlike in the adult, demonstrate expression of anaplastic lymphoma kinase (ALK). In recent years, the understanding of the biology and molecular features of these aggressive lymphomas has increased tremendously. This has led to reclassification of newer PYA entities including Burkitt-like lymphoma with 11q aberration. In this review, we will discuss the current progress discovered in frequently encountered aggressive NHLs in the PYA, highlighting the clinical, pathologic and molecular features that aid in the diagnosis of these aggressive lymphomas. We will be updating the new concepts and terminologies used in the new classification systems.

Molecular Characterization of Primary Mediastinal Large B-Cell Lymphomas

Since the description of primary mediastinal large B-cell lymphoma (PMBL) as a distinct entity from diffuse large B-cell lymphomas (DLBCL), numerous studies have made it possible to improve their definition. Despite this, this differential diagnosis can be challenging in daily practice. However, in some centers, PMBL may be treated according to a particular regimen, distinct from those used in DLBCL, emphasizing the importance of accurate identification at diagnosis. This study aimed to describe the histological and molecular characteristics of PMBL to improve the accuracy of their diagnosis. Forty-nine cases of PMBL were retrospectively retrieved. The mean age at diagnosis was 39 years (21-83), with a sex ratio of 0.88. All cases presented a fibrous background with diffuse growth of intermediate to large cells with an eosinophil (26/49, 53%) or retracted cytoplasm (23/49, 47%). "Hodgkin-like" cells were observed in 65% of cases (32/49, 65%). The phenotype was: BCL6+ (47/49, 96%), MUM1+ (40/49, 82%), CD30+ (43/49, 88%), and CD23+ (37/49, 75%). Genomic DNAs were tested by next generation sequencing of 33 cases using a custom design panel. Pathogenic variants were found in all cases. The most frequent mutations were: SOCS1 (30/33, 91%), TNFAIP3 (18/33, 54.5%), ITPKB (17/33, 51.5%), GNA13 (16/33, 48.5%), CD58 (12/33, 36.4%), B2M (12/33; 36.4%), STAT6 (11/33, 33.3%) as well as ARID1A (10/33, 30.3%), XPO1 (9/33, 27.3%), CIITA (8/33, 24%), and NFKBIE (8/33, 24%). The present study describes a PMBL cohort on morphological, immunohistochemical, and molecular levels to provide pathologists with daily routine tools. These data also reinforce interest in an integrated histomolecular diagnosis to allow a precision diagnosis as early as possible.

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.

Primary Mediastinal B-Cell Lymphoma Presenting as Cardiac Tamponade

Primary mediastinal B-cell lymphoma (PMBCL) is a rare subtype of non-Hodgkin lymphoma. Typical symptoms include cough, chest pain, and dyspnea; however, cardiac tamponade as the primary manifestation is exceedingly rare. We hereby present a case of a 34-year-old male with a past medical history of obesity, who presented to our emergency department with a chronic dry cough for 4 months. On admission, computed tomography demonstrated a large 11.1-cm diameter anterior mediastinal mass, and echocardiography demonstrated cardiac tamponade physiology. The patient underwent further workup including pericardiocentesis, subsequent pericardial window, and mediastinal biopsy, which demonstrated histopathology consistent with PMBCL. Our case highlights the importance of a complete and thorough workup for patients with chronic untraditional symptoms. This case is unique in that PMBCL is rarely associated with cardiac tamponade as the primary clinical presentation. Additionally, we recommend an extensive cardiac workup for patients presenting with a large mediastinal mass, as failure to do so may result in patient morbidity and mortality.

A case of suspected primary mediastinal large B-cell lymphoma: An uncommon cause of sudden death

Primary mediastinal large B-cell lymphoma (PMLBCL) is an aggressive tumor originating from thymic B-cells. Clinically, it presents with general signs such as cough, chest pain and dyspnea. Although these symptoms are not specific, they are severe enough to reveal the disease. We report an autopsy case of a 25-year-old man, with a recent past history of cough and dyspnea, for which he consulted twice the emergency department and no diagnosis was made. He presented to the Emergency Unit, with a sudden onset of a dyspnea followed by a loss of consciousness. He was shortly declared dead after, a medico-legal autopsy was requested. On external examination, no traumatic lesions on the body were found, an important cyanosis of the face and ears, was, however, found. On autopsy, a mediastinal mass was found, measuring 19 cm × 25 cm and weighing 600 g, extending to the infra-hyoid region and to the thoracic cage and infiltrating the pericardium. Trachea had a necrotic mucosa with a partially obstructive lymph node mass. The diagnosis of a primary mediastinal large B-cell lymphoma was suspected based on pathological and immunohistochemical findings. The cause of death was finally attributed to respiratory failure due to this tumor.

Health-related quality of life with lisocabtagene maraleucel vs standard of care in relapsed or refractory LBCL

Lisocabtagene maraleucel (liso-cel) has shown promising efficacy in clinical trials for patients with relapsed/refractory large B-cell lymphoma (LBCL). We present health-related quality of life (HRQOL) results from the TRANSFORM study, the first comparative analysis of liso-cel vs standard of care (SOC) as second-line therapy in this population. Adults with LBCL refractory or relapsed ≤12 months after first-line therapy and eligible for autologous stem cell transplantation were randomized 1:1 to the liso-cel or SOC arms (3 cycles of immunochemotherapy in which responders proceeded to high-dose chemotherapy and autologous stem cell transplantation). HRQOL was assessed by European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire - 30 items and the Functional Assessment of Cancer Therapy-Lymphoma subscale. Patients with baseline and ≥1 postbaseline assessment were analyzed (liso-cel, n = 47; SOC, n = 43). The proportion of patients with meaningful improvement in global health status/quality of life (QOL) was higher, whereas deterioration was lower in the liso-cel arm vs SOC arm from day 126 to month 6. Mean change scores showed meaningful worsening in global health status/QOL at month 6, fatigue at day 29 and month 6, and pain at month 6 with SOC; mean scores for other domains were maintained or improved in both arms. Time to confirmed deterioration favored the liso-cel arm vs SOC arm in global health status/QOL (median: not reached vs 19.0 weeks, respectively; hazard ratio, 0.47; 95% confidence interval, 0.24-0.94). HRQOL was either improved or maintained from baseline in patients with relapsed/refractory LBCL in the liso-cel arm vs SOC arm as second-line treatment. This study is registered at clinicaltrials.gov as #NCT0357531.

The Cost Effectiveness of Axicabtagene Ciloleucel Versus Best Supportive Care in the Treatment of Adult Patients with Relapsed or Refractory Large B-Cell Lymphoma (LBCL) After Two or More Lines of Systemic Therapy in Canada

BACKGROUND AND OBJECTIVE

Axicabtagene ciloleucel (axi-cel) received marketing authorisation in Canada for the treatment of relapsed or refractory large B-cell lymphoma after two or more lines of systemic therapy, and the clinical and economic value of axi-cel to patients and the healthcare system should be examined. The objective of this analysis is to determine, from societal and public healthcare payer perspectives, the cost effectiveness of axi-cel versus best supportive care for patients with relapsed or refractory large B-cell lymphoma in Canada.

METHODS

A pharmacoeconomic model was developed and populated with clinical data derived from the ZUMA-1 and SCHOLAR-1 studies using a propensity score-matched comparison. A partitioned survival mixture-cure modelling approach was taken to characterise the potential curative effect of axi-cel therapy in large B-cell lymphoma. Healthcare resource utilisation and adverse event data were based on results from ZUMA-1, and utility values were derived from ZUMA-1 data supplemented with published literature. Costs (in 2021 Canadian dollars) were taken from publicly available Canadian cost databases and published literature. Benefits and costs were discounted at 1.5% per year, and sensitivity analyses were conducted to assess the robustness of the results.

RESULTS

In the base case, axi-cel generated an incremental 6.2 life-years compared to best supportive care, corresponding to 4.6 additional quality-adjusted life-years, and was associated with $606,010 in additional costs. The incremental cost-utility ratio was $132,747 per quality-adjusted life-year gained compared with best supportive care from a societal perspective ($106,392 per quality-adjusted life-year gained from a public healthcare payer perspective). Key drivers of the analysis included progression-free survival and overall survival values for axi-cel.

CONCLUSIONS

The results of this analysis suggest that axi-cel may be considered a cost-effective allocation of resources compared with best supportive care for the treatment of adult patients with relapsed or refractory large B-cell lymphoma in Canada.

Cost-effectiveness analysis of axicabtagene ciloleucel vs. salvage chemotherapy for relapsed or refractory adult diffuse large B-cell lymphoma in China

PURPOSE

Axicabtagene ciloleucel (Axi-Cel, 2 × 10⁶ CAR-T cells/kg, single intravenous injection) is a chimeric antigen receptor cell immunotherapy that exhibits favorable clinical efficacy and safety in patients with relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL). However, this treatment is expensive in China. This study aimed to evaluate the cost-effectiveness of Axi-Cel versus salvage chemotherapy for the treatment of R/R DLBCL from the perspective of the Chinese healthcare system.

METHODS

A decision analysis model containing a short-term decision tree and long-term semi-Markov partitioned survival model was developed. The time horizon was 40 years and the period from 10 to 40 years was included in sensitivity analysis. The model was developed based on data from the ZUMA-1 and SCHOLAR-1 trials. Life years, quality-adjusted life years (QALYs), overall costs, and the incremental cost-effectiveness ratio (ICER) were estimated at a willingness to pay (WTP) threshold of US $31,320 per QALY, which is three times the gross domestic product per capita.

RESULTS

The base case analysis revealed that treatment with Axi-Cel is associated with an increased overall cost of US $175,380 and improved effectiveness of 3.43 LYs and 2.61 QALYs compared to salvage chemotherapy, leading to an ICER of US $51,190 per LY and US $67,250 per QALY. The developed model is sensitive to the discount rate, utility of progression-free survival (PFS), and cost of Axi-Cel. The ICER of Axi-Cel was greater than the WTP threshold in the sensitivity and scenario analyses. To achieve cost-effectiveness, the price of Axi-Cel must be reduced by 59.19% to US $71,000.

CONCLUSION

At its current price, Axi-Cel is not likely to be a cost-effective option compared to salvage chemotherapy for adult patients with R/R DLBCL.

A case of solitary plasmacytoma of bone showing co-expression of both immunoglobulin light chains

Background

Solitary plasmacytoma of bone (SPB) is a rare plasma cell neoplasm. It arises in bone as a single locus in the absence of any plasma cell myeloma lesions. Plasma cell neoplasms intrinsically express only one immunoglobulin light chain (IgL)—kappa or lambda—and using this fact, kappa/lambda deviation is the decisive factor for diagnosis. Co-expression of both IgLs in a single tumor cell is extremely rare.

Case presentation

We report a case of SPB that arose in the vertebra of a 52-year-old Japanese woman. Histologically, the resected mass showed diffuse plasma cell proliferation. Dual IgL expression was detected by flow cytometry, immunohistochemistry, and in situ hybridization (ISH) targeting IgL mRNA.

Conclusion

We have presented an extremely rare case of SPB showing dual expression of kappa and lambda IgLs. This unusual case of plasma cell neoplasia might represent a possible exceptional example of failure of “IgL isotypic exclusion.”

Multiple site place-of-care manufactured anti-CD19 CAR-T cells induce high remission rates in B-cell malignancy patients

Chimeric antigen receptor (CAR) T cells targeting the CD19 antigen are effective in treating adults and children with B-cell malignancies. Place-of-care manufacturing may improve performance and accessibility by obviating the need to cryopreserve and transport cells to centralized facilities. Here we develop an anti-CD19 CAR (CAR19) comprised of the 4-1BB co-stimulatory and TNFRSF19 transmembrane domains, showing anti-tumor efficacy in an in vivo xenograft lymphoma model. CAR19 T cells are manufactured under current good manufacturing practices (cGMP) at two disparate clinical sites, Moscow (Russia) and Cleveland (USA). The CAR19 T-cells is used to treat patients with relapsed/refractory pediatric B-cell Acute Lymphocytic Leukemia (ALL; n = 31) or adult B-cell Lymphoma (NHL; n = 23) in two independently conducted phase I clinical trials with safety as the primary outcome (NCT03467256 and NCT03434769, respectively). Probability of measurable residual disease-negative remission was also a primary outcome in the ALL study. Secondary outcomes include complete remission (CR) rates, overall survival and median duration of response. CR rates are 89% (ALL) and 73% (NHL). After a median follow-up of 17 months, one-year survival rate of ALL complete responders is 79.2% (95%CI 64.5‒97.2%) and median duration of response is 10.2 months. For NHL complete responders one-year survival is 92.9%, and median duration of response has not been reached. Place-of-care manufacturing produces consistent CAR-T cell products at multiple sites that are effective for the treatment of patients with B-cell malignancies.

Strategies to address the challenges associated with product manufacturing can improve chimeric antigen receptor (CAR) cell–based therapeutics. Here the authors report the results of two clinical trials in patients with B-cell malignancies, showing that place-of-care manufacturing has a low production failure rate with CD19-directed CAR-T cell products inducing high remission rates.

Comparative analysis of international prognostic indices in gray-zone lymphoma

Gray-zone lymphoma (GZL) reflects an aggressive B-cell neoplasm with features intermediate between diffuse large B-cell lymphoma (DLBCL) and classical Hodgkin lymphoma (cHL). The International Prognostic Index (IPI) and its derivatives (R-IPI, NCCN-IPI, and the Hasenclever IPS) have been established for DLBCL or cHL while the most suitable scoring system for GZL remains undetermined. In an exploratory multi-centric cohort of GZL (n = 61), we performed a comparative analysis of prognostic indices with regard to model fit and mutual concordance. The calculation of the corrected Akaike's information criterion (cAIC) and Harrel's concordance index (c-index) for each scoring system identified the NCCN-IPI to harbor the most convincing prognostic capabilities regarding both overall survival (OS) and progression-free survival (PFS) compared to its enhanced derivatives. The current results affirm the clinical utility of the NCCN-IPI and suggest its preferential use in clinical practice in GZL-patients.

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.

Pembrolizumab in the treatment of refractory primary mediastinal large B-cell lymphoma: safety and efficacy

Introduction: Primary mediastinal large B-cell lymphoma (PMBL) is a rare subtype of lymphoma, clinically and biologically distinct from diffuse large B-cell lymphoma (DLBCL) that shows overlapping features with classical Hodgkin lymphoma (cHL). If first-line strategies lead to 80-85% of curability, relapse occurs early with a chemo-refractory disease and a poor outcome. The presence of 9p24.1 rearrangement, conducting to the overexpression of the immune checkpoint molecules PDL1 and 2, has paved the way for immune checkpoint blockers development in these entities. Pembrolizumab, an anti PD-1 checkpoint antibody, was initially approved in solid cancer and later on in the lymphoma field in cHL.Areas covered: We summarize the biology and clinical need in PMBL, leading to the rationale for checkpoint inhibitors development, as well as pembrolizumab clinical studies in this entity. To do so, we performed a PubMed search using the terms: 'PMBCL,' 'lymphoma,' 'Immune checkpoint,' and 'Pembrolizumab.'Expert opinion: Pembrolizumab showed tolerable safety profile and efficacy data in patients with PMBL who have relapsed after, or are ineligible for autologous stem cell transplant (ASCT). Some combination strategies have shown promising preliminary results, while others are currently being conducted.

Survival among patients with composite and sequential lymphoma between primary mediastinal lymphoma/diffuse large B-cell lymphoma and classical Hodgkin lymphoma: A population-based study

BACKGROUND

Data on composite and sequential lymphoma between primary mediastinal lymphoma/diffuse large B-cell lymphoma (LBCL) and classical Hodgkin lymphoma (cHL) are rare.

METHODS

We identified 25 cases with composite lymphoma (CL), 116 cases developing LBCL as a second primary cancer after cHL (cHL-LBCL), and 74 cases developing cHL as a second primary cancer after LBCL (LBCL-cHL) from the Surveillance, Epidemiology, and End Results (SEER) 18 database. Comparisons of overall survival (OS) and lymphoma cause-specific survival (CSS) between patients with cHL-LBCL or cHL-LBCL and their de novo counterparts were performed.

RESULTS

The 5-year OS of patients with CL was 74.8 %. No significant difference in unadjusted OS and lymphoma CSS were observed between patients with de novo LBCL (LBCL-1 group) and patients with cHL-LBCL. However, the age- and stage-adjusted cHL-LBCL group had inferior OS and lymphoma CSS compared with that in the LBCL-1 group. The unadjusted and adjusted OS and lymphoma CSS in the LBCL-cHL group were significantly worse than patients with de novo cHL.

CONCLUSIONS

CL between LBCL and cHL may have good outcomes. cHL survivors had poorer outcomes after a LBCL diagnosis versus patients with LBCL-1. Significantly poor outcomes were observed in patients with LBCL-cHL compared with patients with de novo cHL.

Innovative therapeutic strategy for B-cell malignancies that combines obinutuzumab and cytokine-induced killer cells

Background

Patients affected by aggressive B-cell malignancies who are resistant to primary or salvage chemoimmunotherapy have an extremely poor prognosis and limited therapeutic options. Promising therapeutic success has been achieved with the infusion of CD19 chimeric antigen receptor-T cells, but several limits still restrain the administration to a limited proportion of patients. This unmet clinical need might be fulfilled by an adoptive immunotherapy approach that combines cytokine-induced killer (CIK) cells and monoclonal antibodies (mAb) to the CD20 antigen. Indeed, CIK cells are an effector population endowed with antitumor activity, which can be further improved and antigen-specifically redirected by clinical-grade mAb triggering antibody-dependent cell-mediated cytotoxicity.

Methods

CIK cells were generated from peripheral blood of patients affected by different B-cell malignancies using a blinatumomab-based cell culture protocol. Effector cells were combined with the anti-CD20 mAb obinutuzumab and their therapeutic activity was assessed both in vitro and in vivo.

Results

CIK cells were successfully expanded in clinically relevant numbers, starting from small volumes of peripheral blood with extremely low CD3⁺ counts and high tumor burden. This relied on the addition of blinatumumab in culture, which leads to the simultaneous expansion of effector cells and the complete elimination of the neoplastic component. Moreover, CIK cells were highly cytotoxic in vitro against both B-cell tumor cell lines and autologous neoplastic targets, and had a significant therapeutic efficacy against a B-cell malignancy patient-derived xenograft on in vivo transfer.

Conclusions

The combination of an easily expandable CIK cell effector population with a mAb already in clinical use establishes a tumor antigen-specific redirection strategy that can be rapidly translated into clinical practice, providing an effective therapeutic alternative for B-cell malignancies without any need for genetic modifications. Additionally, the approach can be potentially applied to an extremely vast array of different tumors by simply substituting the targeting mAb.

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.

The impact of modern radiotherapy on radiation-induced late sequelae: Focus on early-stage mediastinal classical Hodgkin Lymphoma. A critical review by the Young Group of the Italian Association of Radiotherapy and Clinical Oncology (AIRO)

INTRODUCTION

The historically feared radiation-induced secondary cancers and cardiac toxicities observed among mediastinal classical Hodgkin Lymphoma (cHL) patients may still negatively burden the benefit of radiotherapy among long-term survivors. Modern radiotherapy (RT) delivery techniques, including intensity-modulated RT (IMRT) and deep inspiration breath-hold (DIBH) solutions, are drastically changing this scenario. Results of a literature overview are reported and discussed in this paper.

MATERIALS AND METHODS

Key references were derived from a PubMed query. Hand searching and clinicaltrials.gov were also used.

RESULTS

This paper contains a narrative report and a critical discussion of organs-at-risk dose-volume metrics linked with radiation-induced toxicities in cHL patients.

CONCLUSIONS

The scenario of early-stage cHL presents long-life expectancies, thus the goal of treatment should aim at maintaining high cure rates and limiting the onset of late complications. Further evaluations of dosimetric measures and clinical outcomes are warranted to identify patients at higher risk to target treatment tailoring.

Cell-Free DNA for the Management of Classical Hodgkin Lymphoma

Cell-free DNA (cfDNA) testing, is an emerging “liquid biopsy” tool for noninvasive lymphoma detection, and an increased amount of data are now available to use this technique with accuracy, especially in classical Hodgkin lymphoma (cHL). The advantages of cfDNA include simplicity of repeated blood sample acquisition over time; dynamic, noninvasive, and quantitative analysis; fast turnover time; reasonable cost; and established consistency with results from tumor genomic DNA. cfDNA analysis offers an easy method for genotyping the overall molecular landscape of pediatric and adult cHL and may help in cases of diagnostic difficulties between cHL and other lymphomas. cfDNA levels are correlated with clinical, prognostic, and metabolic features, and may serve as a therapeutic response evaluation tool and as a minimal residual disease (MRD) biomarker in complement to positron emission tomography (PET). Indeed, cfDNA real-time monitoring by fast high-throughput techniques enables the prompt detection of refractory disease or may help to address PET residual hypermetabolic situations during or at the end of treatment. The major recent works presented and described here demonstrated the clinically meaningful applicability of cfDNA testing in diagnostic and theranostic settings, but also in disease risk assessment, therapeutic molecular response, and monitoring of cHL treatments.

Immune-Checkpoint Inhibitors in B-Cell Lymphoma

Simple Summary

Immune-based treatment strategies, which include immune checkpoint inhibition, have recently become a new frontier for the treatment of B-cell-derived lymphoma. Whereas checkpoint inhibition has given oncologists and patients hope in specific lymphoma subtypes like Hodgkin lymphoma, other entities do not benefit from such promising agents. Understanding the factors that determine the efficacy and safety of checkpoint inhibition in different lymphoma subtypes can lead to improved therapeutic strategies, including combinations with various chemotherapies, biologics and/or different immunologic agents with manageable safety profiles.

Abstract

For years, immunotherapy has been considered a viable and attractive treatment option for patients with cancer. Among the immunotherapy arsenal, the targeting of intratumoral immune cells by immune-checkpoint inhibitory agents has recently revolutionised the treatment of several subtypes of tumours. These approaches, aimed at restoring an effective antitumour immunity, rapidly reached the market thanks to the simultaneous identification of inhibitory signals that dampen an effective antitumor response in a large variety of neoplastic cells and the clinical development of monoclonal antibodies targeting checkpoint receptors. Leading therapies in solid tumours are mainly focused on the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed death 1 (PD-1) pathways. These approaches have found a promising testing ground in both Hodgkin lymphoma and non-Hodgkin lymphoma, mainly because, in these diseases, the malignant cells interact with the immune system and commonly provide signals that regulate immune function. Although several trials have already demonstrated evidence of therapeutic activity with some checkpoint inhibitors in lymphoma, many of the immunologic lessons learned from solid tumours may not directly translate to lymphoid malignancies. In this sense, the mechanisms of effective antitumor responses are different between the different lymphoma subtypes, while the reasons for this substantial difference remain partially unknown. This review will discuss the current advances of immune-checkpoint blockade therapies in B-cell lymphoma and build a projection of how the field may evolve in the near future. In particular, we will analyse the current strategies being evaluated both preclinically and clinically, with the aim of fostering the use of immune-checkpoint inhibitors in lymphoma, including combination approaches with chemotherapeutics, biological agents and/or different immunologic therapies.

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.

Primary CD20-positive mediastinal diffuse large B-cell lymphoma

Primary mediastinal B-cell lymphoma (PMBCL) is a rare tumour with different characteristics from other type of lymphomas. Clinical manifestations may vary and cause delay in diagnosis and management. We present a 22-year-old patient with symptoms of shortness of breath, weight loss, and night sweats. Laboratory studies only showed a markedly high lactate dehydrogenase (LDH) level and thoracic computed tomography (CT)scan revealed a large mediastinal mass. Core biopsy-guided CT scan was performed and the pathological and immunohistochemistry established a PMBCL diagnosis. We administered Rituximab Dose-Adjusted Etoposide Prednisolone Vincristine Cyclophosphamide Doxorubicin (R-DA-EPOCH) chemotherapy regimen and the patient responded well to treatment. This is an example of rare case of mediastinal lymphoma with challenges to overcome to achieve diagnostic and therapeutic success. Failure to differentiate PMBCL with other systemic diffuse large B-cell lymphoma (DLBCL) could skew treatment algorithm and prevent optimal response. Administration of proper systemic therapy, especially in young, low-risk patients could yield excellent outcome.

Patient selection for chimeric antigen receptor (CAR) T-cell therapy for aggressive B-cell non-Hodgkin lymphomas

CAR T-cells have transformed the therapeutic landscape for patients with relapsed/refractory aggressive B-cell lymphomas. Currently, three CAR T-cell products are approved or soon to be approved: axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene maraleucel. These products differ in construct, manufacturing, clinical trial design and toxicity profile. Patient selection for CAR T-cells, and the ideal product for a given patient, involves myriad considerations including age, fitness, prior therapies, comorbid diseases, organ function, logistics of administration, turnaround time, and institutional familiarity. This article reviews the proper patient and product selection for the management of patients with relapsed/refractory aggressive B-cell lymphomas.

Use of checkpoint inhibitors in gray zone lymphoma

Checkpoint inhibitors, cancer immunotherapies, are the new forms of treatment for gray zone lymphoma, a rare subtype that combines the characteristics of both Hodgkin and non-Hodgkin disease forms. Programmed cell death protein 1/programmed cell death ligand 1 (PD-L1/PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) modulate the immune system function. Immunological checkpoints can be stimulatory or inhibitory, and tumors can use these checkpoints to protect against immune system attacks. This is a case report of a difficult diagnosis and describes the most current treatment using checkpoint inhibitors, through the review of the clinical record of a patient diagnosed with gray area lymphoma in August 2019, using a descriptive and cross-sectional analysis of the clinical history and disease evolution. The case showed that pembrolizumab therapy is an effective treatment option for patients with rare gray zone lymphoma refractory to different lines of treatment. Both the diagnosis and treatment of gray area lymphoma remain a challenge for the medical and multiprofessional teams, and collaboration between them ensured effective treatment for the patient.

Comparative pathologic analysis of mediastinal B-cell lymphomas: selective expression of p63 but no GATA3 optimally differentiates primary mediastinal large B-cell lymphoma from classic Hodgkin lymphoma

Background

Interpretation of mediastinal biopsy is often challenging even for experienced pathologists especially when a hematolymphoid neoplasm is suspected. Primary mediastinal large B-cell lymphoma (PMLBCL) and classic Hodgkin lymphoma (CHL) represent two major types of mature B-cell lymphomas of the mediastinum. Although PMLBCL and mediastinal CHL share many clinicopathologic characteristics, their treatment strategies and responses are remarkably different. We therefore aimed to find distinctive histologic or protein markers to better differentiate these two lesions.

Methods

Search for primary mediastinal B-cell lymphomas found 52 consecutive cases from 3 university hospitals of Korea during 2005 to 2012. Among them, 32 cases that were available for additional immunohistochemistry (IHC) assessment were enrolled in this study. These cases consisted of the following: CHL (N = 13), PMLBCL (N = 16), and B-cell lymphoma unclassifiable, with features intermediate between diffuse large B-cell lymphoma and CHL (gray zone lymphoma, N = 3). Along with the clinicopathologic findings, the expression of p63, GATA3 and cyclin E was investigated by IHC in the three categorized lesions mentioned above.

Results

Most clinical features overlapped between PMLBCL and CHL except for the increased disease progression and mortality found in PMLBCL. In the pathologic review, the presence of epithelioid granuloma favored a diagnosis of CHL, whereas reticulated or alveolar patterns of fibrosis were characteristic of PMLBCL. For protein markers, p63 was predominantly positive in PMLBCL (15/16) compared with CHL (2/13), which indicates that p63 is a marker of the highest diagnostic accuracy when calculated by the area under the ROC curve. GATA3 was expressed in the majority of CHL cases (10/13) compared with PMLBCL (0/16), while the expression of cyclin E was only rarely present in a minor population of PMLBCL.

Conclusions

P63 expression in tumor cells, even focal expression, and no GATA3 is the most helpful feature in distinguishing PMLBCL from mediastinal CHL.

Nivolumab Combined With Brentuximab Vedotin for Relapsed/Refractory Primary Mediastinal Large B-Cell Lymphoma: Efficacy and Safety From the Phase II CheckMate 436 Study

PURPOSE

Primary mediastinal B-cell lymphoma (PMBL) is a rare but aggressive non-Hodgkin lymphoma with poor outcomes in patients with relapsed/refractory (R/R) disease. PMBL is characterized by high expression of programmed death-1 ligand and variable expression of CD30. Nivolumab, an anti-programmed death-1 immune checkpoint inhibitor, and brentuximab vedotin (BV), an anti-CD30 antibody-drug conjugate, may have synergistic activity in R/R PMBL.

METHODS

The expansion cohort of the open-label, phase I/II CheckMate 436 study enrolled patients with confirmed R/R PMBL who were previously treated with either autologous hematopoietic cell transplantation or two or more prior chemotherapy regimens if ineligible for autologous hematopoietic cell transplantation. Patients received nivolumab (240 mg intravenously) and BV (1.8 mg/kg intravenously) every 3 weeks until disease progression or unacceptable toxicity. Primary end points were investigator-assessed objective response rate (ORR) per the Lugano 2014 criteria and safety.

RESULTS

Thirty patients with PMBL were treated and evaluable. At a median follow-up of 11.1 months, ORR (95% CI) was 73% (54% to 88%), with a 37% complete remission rate per investigator, and ORR of 70% (51% to 85%), with a 43% complete metabolic response rate per independent review. Median duration of response, median progression-free survival, and median overall survival have not been reached. Eleven responders had consolidation with autologous (n = 5) or allogeneic (n = 6) transplantation. Treatment-related adverse events were reported in 25 patients (83%). Sixteen patients (53%) had grade 3 to 4 treatment-related adverse events; the most common were neutropenia (n = 9), thrombocytopenia (n = 3), and peripheral neuropathy (n = 3). There were no treatment-related deaths.

CONCLUSION

In patients with R/R PMBL, the combination of nivolumab plus BV represents a promising option, with high antitumor activity and a manageable safety profile.

Challenges in the Diagnosis of Gray Zone Lymphomas

The diagnosis of B-cell lymphoma unclassifiable with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, also called gray zone lymphoma (GZL), is frequently challenging. Incorrect diagnosis as either classic Hodgkin lymphoma or diffuse large B-cell lymphoma has significant implications for choice of upfront therapy based on recent large multi-institutional series from the United States and Europe. These studies have clarified some diagnostic challenges and provided guidance on the spectrum of morphologic features in this entity. This article clarifies some of the diagnostic conundrum surrounding GZL and provides an evidence-based approach to GZL diagnosis using morphology and immunohistochemistry.

A Rare Case of Grey Zone Lymphoma Successfully Treated with Brentuximab Vedotin and R-CHP Chemotherapy

Introduction

The diagnosis of B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma (DLBCL) and classical Hodgkin's lymphoma (cHL), also referred to as grey zone lymphoma (GZL), is a challenging diagnosis. There are no standardized guidelines; however, evidence strongly suggests that DLBCL-based regimens are effective in the treatment of GZL. Brentuximab vedotin (BV) is an anti-CD30 antibody drug conjugate that has established efficacy in relapsed/refractory Hodgkin and some T-cell lymphomas. There is some evidence that BV has a positive response in non-Hodgkin lymphoma (NHL) with a wide range of CD30 expressions—including GZL.

Case

We present a case of a patient initially diagnosed with cHL who underwent repeat biopsy which was revealed to be GZL. Based on PET scanning and immunohistochemical studies, she was classified as a stage IIIA CD20+/CD30+ GZL patient. Given her strong CD30 expression, she underwent 6 cycles of R-BV-CHP (rituximab, brentuximab vedotin, cyclophosphamide, doxorubicin, and prednisone) chemotherapy and achieved complete response (CR) both clinically and radiographically.

Discussion

Given the rarity of GZL, this case illustrates the immense challenges in making the diagnosis, discusses the current treatment options, and suggests that BV may be a viable therapeutic candidate in the treatment of GZL.

NOD-like receptors: major players (and targets) in the interface between innate immunity and cancer

Innate immunity comprises several inflammation-related modulatory pathways which receive signals from an array of membrane-bound and cytoplasmic pattern recognition receptors (PRRs). The NLRs (NACHT (NAIP (neuronal apoptosis inhibitor protein), C2TA (MHC class 2 transcription activator), HET-E (incompatibility locus protein from Podospora anserina) and TP1 (telomerase-associated protein) and Leucine-Rich Repeat (LRR) domain containing proteins) relate to a large family of cytosolic innate receptors, involved in detection of intracellular pathogens and endogenous byproducts of tissue injury. These receptors may recognize pathogen-associated molecular patterns (PAMPs) and/or danger-associated molecular patterns (DAMPs), activating host responses against pathogen infection and cellular stress. NLR-driven downstream signals trigger a number of signaling circuitries, which may either initiate the formation of inflammasomes and/or activate nuclear factor κB (NF-κB), stress kinases, interferon response factors (IRFs), inflammatory caspases and autophagy. Disruption of those signals may lead to a number of pro-inflammatory conditions, eventually promoting the onset of human malignancies. In this review, we describe the structures and functions of the most well-defined NLR proteins and highlight their association and biological impact on a diverse number of cancers.

Germinal center-derived lymphomas: The darkest side of humoral immunity

One of the unusual features of germinal center (GC) B cells is that they manifest many hallmarks of cancer cells. Accordingly, most B-cell neoplasms originate from the GC reaction, and characteristically display abundant point mutations, structural genomic lesions, and clonal diversity from the genetic and epigenetic standpoints. The dominant biological theme of GC-derived lymphomas is mutation of genes involved in epigenetic regulation and immune receptor signaling, which come into play at critical transitional stages of the GC reaction. Hence, mechanistic studies of these mutations reveal fundamental insight into the biology of the normal and malignant GC B cell. The BCL6 transcription factor plays a central role in establishing the GC phenotype in B cells, and most lymphomas are dependent on BCL6 to maintain survival, proliferation, and perhaps immune evasion. Many lymphoma mutations have the commonality of enhancing the oncogenic functions of BCL6, or overcoming some of its tumor suppressive effects. Herein, we discuss how unique features of the GC reaction create vulnerabilities that select for particular lymphoma mutations. We examine the interplay between epigenetic programming, metabolism, signaling, and immune regulatory mechanisms in lymphoma, and discuss how these are leading to novel precision therapy strategies to treat lymphoma patients.

Lymphoma in Adolescents and Young Adults: Current Perspectives

Lymphomas in adolescents and young adults represent approximately one quarter of all cancers in this age group. Historically, adolescent and young adult cancer patients represent a unique population with diverging issues surrounding psychosocial hardships/barriers, economics, and lack of standardization of therapeutic approaches.Furthermore, the biologic differences within the adolescent and young adult population seen in various lymphoma subtypes likely play a role in overall outcomes for this group. Without an organized approach to clinical and translational research for adolescent and young adult patients within specialized treatment centers, this population may continue to experience inferior results. Here we look at the current perspectives of adolescent and young adult lymphomas with respect to disease biology, clinical characteristics, treatment, and prognosis of this unique lymphoma population.

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.

The promise of CAR T-cell therapy in aggressive B-cell lymphoma

Relapsed or refractory aggressive B-cell lymphoma has an extremely poor prognosis and efforts to develop novel therapies for these patients have failed for almost four decades until the advent of chimeric antigen receptor (CAR) T-cell therapy. Within the last one year, two anti-CD19 CAR T-cell therapy products, axicabtagene ciloleucel and tisagenlecleucel, were approved by the United States Food and Drug Administration for the treatment of relapsed or refractory large B-cell lymphoma after at least two lines of systemic therapy based on multicenter single-arm phase two clinical trials. Here, we will discuss the different components of the CAR construct and their mechanisms of action, the role of conditioning chemotherapy, the efficacy and toxicity observed with anti-CD19 CAR T-cell therapies in aggressive B-cell lymphomas, and emerging strategies to further improve the safety and efficacy of these highly promising approaches.

NHL in adolescents and young adults: A unique population

Non-Hodgkin lymphoma (NHL) is a heterogeneous group of lymphoid malignancies with high incidence in adolescents and young adults (AYAs). The most common diseases include diffuse large B-cell lymphoma, anaplastic large cell lymphoma, Burkitt lymphoma, lymphoblastic lymphoma, and primary mediastinal large B-cell lymphoma. In comparison to younger children and adults, AYAs (15-39 years) with NHL present a specific set of challenges including variations in tumor biology, inconsistent treatment, pharmacodynamics, and psychosocial barriers. While survival of AYAs with NHL has improved, cure rates remain suboptimal. Incorporation of novel agents into pediatric-inspired treatment regimens specifically designed for NHL in AYAs has led to improved outcomes. Consideration of AYAs as a distinct population in the diagnosis and treatment of NHL is encouraged.

Autologous stem cell transplantation for primary mediastinal B-cell lymphoma: long-term outcome and role of post-transplant radiotherapy. A report of the European Society for Blood and Marrow Transplantation

The purpose of this retrospective registry study was to investigate the outcome of autoSCT for primary mediastinal B-cell lymphoma (PMBCL) in the rituximab era, including the effects of eventual post-transplant radiotherapy (RT) consolidation. Patients with PMBCL aged between 18 and 70 years who were treated with a first autoSCT between 2000 and 2012 and registered with the EBMT were eligible. Eighty-six patients with confirmed PMBCL and the full data set required for this analysis were evaluable. Sixteen patients underwent autoSCT in remission after first-line therapy (CR/PR1), 44 patients were transplanted with chemosensitive relapsed or primary refractory disease (CR/PR >1), and 24 patients were chemorefractory at the time of autoSCT. With a median follow-up of 5 years, 3-year estimates of relapse incidence, progression-free survival, and overall survival were 6%, 94%, and 100% for CR/PR1; 31%, 64%, and 85% for CR/PR >1; and 52%, 39%, and 41% for REF, respectively. Whilst there was no significant benefit of post-transplant RT in the CR/PR >1 group, RT could completely prevent disease recurrence post d100 in the refractory group. In conclusion, autoSCT with or without consolidating RT is associated with excellent outcome in chemoimmunotherapy-sensitive PMBCL, whereas its benefits seem to be limited in chemoimmunotherapy-refractory disease.

Role of Bruton's tyrosine kinase in B cells and malignancies

Bruton’s tyrosine kinase (BTK) is a non-receptor kinase that plays a crucial role in oncogenic signaling that is critical for proliferation and survival of leukemic cells in many B cell malignancies. BTK was initially shown to be defective in the primary immunodeficiency X-linked agammaglobulinemia (XLA) and is essential both for B cell development and function of mature B cells. Shortly after its discovery, BTK was placed in the signal transduction pathway downstream of the B cell antigen receptor (BCR). More recently, small-molecule inhibitors of this kinase have shown excellent anti-tumor activity, first in animal models and subsequently in clinical studies. In particular, the orally administered irreversible BTK inhibitor ibrutinib is associated with high response rates in patients with relapsed/refractory chronic lymphocytic leukemia (CLL) and mantle-cell lymphoma (MCL), including patients with high-risk genetic lesions. Because ibrutinib is generally well tolerated and shows durable single-agent efficacy, it was rapidly approved for first-line treatment of patients with CLL in 2016. To date, evidence is accumulating for efficacy of ibrutinib in various other B cell malignancies. BTK inhibition has molecular effects beyond its classic role in BCR signaling. These involve B cell-intrinsic signaling pathways central to cellular survival, proliferation or retention in supportive lymphoid niches. Moreover, BTK functions in several myeloid cell populations representing important components of the tumor microenvironment. As a result, there is currently a considerable interest in BTK inhibition as an anti-cancer therapy, not only in B cell malignancies but also in solid tumors. Efficacy of BTK inhibition as a single agent therapy is strong, but resistance may develop, fueling the development of combination therapies that improve clinical responses. In this review, we discuss the role of BTK in B cell differentiation and B cell malignancies and highlight the importance of BTK inhibition in cancer therapy.