Different biological risk factors in young poor-prognosis and elderly patients with diffuse large B-cell lymphoma

Myc rearrangement and concurrent high protein expression of C-Myc/Bcl2 carry an adverse prognosis in diffuse large B-cell lymphoma

PURPOSE

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous group of non-Hodgkin lymphoma, characterized by a variety of clinicopathological, histomorphological, immunophenotypic, and molecular genetic features. The subtype of DLBCL known as double-expressor lymphoma (DEL) is associated with an adverse prognosis when treated with R-CHOP. Our study aimed to investigate the clinicopathologic features of DEL and the prognostic roles of Myc rearrangement and C-Myc expression in DEL patients.

PATIENTS AND METHODS

We conducted a retrospective study of 145 patients who were identified through fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) testing.

RESULTS

We found that DEL patients were more likely to have a non-germinal center B-cell (GCB) subtype, stage III/IV disease, and a high International Prognostic Index (IPI) score. Our survival analysis indicated that Myc rearrangement and C-Myc expression were associated with poor prognosis. Although DEL patients with Myc rearrangement exhibited trends towards worse survival compared with patients without Myc rearrangement, the differences were not statistically significant (P = 0.4008). The median overall survival (OS) of DEL patients with ≥70 % C-Myc expression (DEL-C-Mychigh) was 5 months. In the DEL-C-Mychigh group, the non-GCB subtype showed nonsignificant trends towards poorer survival compared with the GCB subtype (P = 0.1042).

CONCLUSION

In conclusion, our study shows that a cut-off of ≥70 % for C-Myc expression in DEL patients can improve risk stratification, and suggests that more intensive treatment regimens may be necessary to improve survival in this high-risk population.

Altered serum lipid levels are associated with prognosis of diffuse large B cell lymphoma and influenced by utility of rituximab

Diffuse large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma, and the prognosis of the disease varied. This research aims to investigate the impact of serum lipid level on the outcome of DLBCL patients and their interaction with rituximab (RTX). Data of newly diagnosed DLBCL in the third affiliated hospital of Soochow University were retrospectively collected. Baseline serum lipid levels, clinical data, and survival information were simultaneously recorded. Data of healthy controls were collected with age matching. Serum lipid levels significantly differed for the patients. All were transformed into categorical variables for the analysis of survival. During a median follow-up of 58 months, 32.8% patients died. Univariate analysis revealed all serum lipid indicators were associated with overall survival (OS); all except for total cholesterol (TC) and apolipoprotein B (apoB) showed significant impact on progression-free survival (PFS). Multivariable analysis confirmed the adverse effect of triglyceride (TG) on PFS (P = 0.013) and favorable impact of high-density lipoprotein (HDL) on OS (P = 0.003). For cases treated without RTX, apolipoprotein A (apoA) had independent favorable effect on both PFS (P = 0.004) and OS (P = 0.001). Comparably, for patients who received RTX, HDL showed remarkably predictive value of PFS (P = 0.011) and OS (P = 0.019). In conclusion, the abnormal serum lipids occurred throughout the course of DLBCL, and the associations of serum lipids and the prognosis of the disease were interfered by RTX. Trial registration: 2022()CL033; June 26, 2022, retrospectively registered.

Genetic Profiling of Diffuse Large B-Cell Lymphoma: A Comparison Between Double-Expressor Lymphoma and Non-Double-Expressor Lymphoma

INTRODUCTION

Data are limited regarding the genetic profiling of diffuse large B-cell lymphoma (DLBCL) with double expression of MYC and BCL2 proteins without underlying rearrangements (double-expressor lymphoma [DEL]). This study aimed to describe the genetic profiling and determine the prognostic significance in patients with DEL and in those with non-DEL.

METHODS

Capture-based targeted sequencing was performed on 244 patients with de novo DLBCL, not otherwise specified. Immunohistochemistry staining was performed for evaluating the MYC and BCL2 expression.

RESULTS

Among 244 patients, 46 patients had DEL, and 198 had non-DEL. KMT2D, CD58, EP300, PRDM1, TNFAIP3 and BCL2 gain or amplification (BCL2^GA/AMP) were significantly more frequently altered in the DEL group. Alterations in the BCR/TLR (p = 0.021), B-cell development and differentiation (p = 0.004), and NF-κB (p = 0.034) pathways occurred more frequently in patients with DEL. Thirty-seven DEL patients and 132 non-DEL patients were included for survival analyses. DEL was not significantly associated with progression-free survival (PFS) (p = 0.60) and overall survival (OS) (p = 0.49). In DEL patients, after adjusting for the International Prognostic Index, BCL2 alteration (HR 2.516, 95% CI 1.027-6.161; p = 0.044) remained an independent predictor of inferior PFS. BCL2^GA/AMP also predicted poor PFS, but with marginal statistical significance (HR 2.489, 95% CI 0.995-6.224; p = 0.051).

CONCLUSION

There was difference in profiling of altered genes and signaling pathways between the DEL group and the non-DEL group. The presence of DEL alone should not be considered as an adverse prognostic indicator, and BCL2 alteration could define a subset of patients with poor prognosis within DEL.

Clinicopathologic Features and Genomic Signature of De Novo CD5+ Diffuse Large B-Cell Lymphoma: A Multicenter Collaborative Study

De novo CD5+ diffuse large B-cell lymphoma (DLBCL) has poor survival in the era of immunochemotherapy. Accurate gene-based typing and prognostic stratification can enhance the development of effective individualized treatments. Therefore, we conducted a multicenter retrospective study to evaluate the clinicopathologic characteristics, genomic profiles, and prognostic parameters of 61 patients with CD5+ DLBCL and 60 patients with CD5- DLBCL, with the goal of facilitating accurate prognostic stratification and potential individualized treatment strategies. Compared with patients with CD5- DLBCL, older age, advanced stage, higher incidence of central nervous system involvement, and MYC/BCL-2 and p53 overexpression were more prevalent in CD5+ DLBCL. Most patients with CD5+ DLBCL had lymph nodes with non-germinal center B-cell-like or activated B-cell-like subtype according to immunohistochemistry or Lymph2Cx assay. Next-generation sequencing showed that the proportion of MCD subtype (based on the co-occurrence of MYD88 and CD79B mutations) in the CD5+ DLBCL cohort was higher than that in the CD5- DLBCL cohort (54.2% vs. 13.0%, P=0.005). Compared with the CD5- cohort, CD5+ DLBCL patients showed poor 5-year overall survival (70.9% vs. 39.0%, P<0.001). Kaplan-Meier survival analysis indicated that cell of origin, MYC/BCL-2, p53, and BCL-6 expression did not have a prognostic impact on patients with CD5+ DLBCL. Multivariate analysis showed that age above 76 years, advanced stage, higher incidence of central nervous system involvement, and hypoalbuminemia were independent factors for poor prognosis in CD5+ DLBCL patients. In summary, CD5+ DLBCL displays poor prognosis, distinctive clinicopathologic characteristics and predominant genetic features of activated B-cell-like and MCD subtypes with worse survival outcome.

Identifying aggressive subsets within diffuse large B-cell lymphoma: implications for treatment approach

INTRODUCTION

While the majority of patients diagnosed with diffuse large B-cell lymphoma (DLBCL) can be cured with front-line chemoimmunotherapy, a subset of patients with high-risk disease remain challenging to treat. Identification of high-risk DLBCL is important as future therapy options are explored.

AREAS COVERED

We discuss the clinical, pathologic and molecular risk stratification in DLBCL and how these factors are incorporated into the decision making for the front-line therapy.

EXPERT OPINION

Clinical and pathological risk stratification has long been the standard for identifying likelihood of future disease progression and overall survival; however, these prediction models lack the granularity of individual patient pathology and response to therapy. Molecular subtypes defined through whole exome sequencing have independent prognostic significance. While identifying molecular drivers of aggressive disease has provided the opportunity to analyze novel therapy combinations with front-line chemoimmunotherapy, only modest benefit has been observed when targeting DLBCL subtypes. Combining clinical, pathologic, and molecular data will likely result in significant improvement in our ability to identify the most aggressive DLBCL subsets. Novel therapies and trial designs will continue to play an important role as we target these at-risk populations in the future.

Molecular Subgroups of Diffuse Large B Cell Lymphoma: Biology and Implications for Clinical Practice

Purpose of Review

Genomic analyses have immensely advanced our conception of the heterogeneity of diffuse large B cell lymphoma (DLBCL), resulting in subgroups with distinct molecular profiles. In this review, we summarize our current knowledge of the biology of DLBCL complexity and discuss the potential implications for precision medicine.

Recent Findings

During the last two decades, gene expression profiling, copy number analysis, and high throughput sequencing enabled the identification of molecular subclasses of DLBCL that are biologically and clinically meaningful. The resulting classifications provided novel prospects of diagnosis, prognostication, and therapeutic strategies for this aggressive disease.

Summary

The molecular characterization of DLBCL offers unprecedented insights into the biology of these lymphomas that can guide precision medicine. The knowledge of the molecular setup of an individual DLBCL patients enables prognostication of patients and will be useful to stratify patients in clinical trials. Future direction should focus to implement the molecular classifications of DLBCL in the clinical practice to evaluate their significance and scope using real-world data.

Genetic Subtyping and Phenotypic Characterization of the Immune Microenvironment and MYC/BCL2 Double Expression Reveal Heterogeneity in Diffuse Large B-cell Lymphoma

PURPOSE

Diffuse large B-cell lymphoma (DLBCL) is molecularly and clinically heterogeneous, and can be subtyped according to genetic alterations, cell-of-origin, or microenvironmental signatures using high-throughput genomic data at the DNA or RNA level. Although high-throughput proteomic profiling has not been available for DLBCL subtyping, MYC/BCL2 protein double expression (DE) is an established prognostic biomarker in DLBCL. The purpose of this study is to reveal the relative prognostic roles of DLBCL genetic, phenotypic, and microenvironmental biomarkers.

EXPERIMENTAL DESIGN

We performed targeted next-generation sequencing; IHC for MYC, BCL2, and FN1; and fluorescent multiplex IHC for microenvironmental markers in a large cohort of DLBCL. We performed correlative and prognostic analyses within and across DLBCL genetic subtypes and MYC/BCL2 double expressors.

RESULTS

We found that MYC/BCL2 double-high-expression (DhE) had significant adverse prognostic impact within the EZB genetic subtype and LymphGen-unclassified DLBCL cases but not within MCD and ST2 genetic subtypes. Conversely, KMT2D mutations significantly stratified DhE but not non-DhE DLBCL. T-cell infiltration showed favorable prognostic effects within BN2, MCD, and DhE but unfavorable effects within ST2 and LymphGen-unclassified cases. FN1 and PD-1-high expression had significant adverse prognostic effects within multiple DLBCL genetic/phenotypic subgroups. The prognostic effects of DhE and immune biomarkers within DLBCL genetic subtypes were independent although DhE and high Ki-67 were significantly associated with lower T-cell infiltration in LymphGen-unclassified cases.

CONCLUSIONS

Together, these results demonstrated independent and additive prognostic effects of phenotypic MYC/BCL2 and microenvironment biomarkers and genetic subtyping in DLBCL prognostication, important for improving DLBCL classification and identifying prognostic determinants and therapeutic targets.

Advances in Lymphoma Molecular Diagnostics

Lymphomas encompass a diverse group of malignant lymphoid neoplasms. Over recent years much scientific effort has been undertaken to identify and understand molecular changes in lymphomas, resulting in a wide range of genetic alterations that have been reported across all types of lymphomas. As many of these changes are now incorporated into the World Health Organization’s defined criteria for the diagnostic evaluation of patients with lymphoid neoplasms, their accurate identification is crucial. Even if many alterations are not routinely evaluated in daily clinical practice, they may still have implications in risk stratification, treatment, prognosis or disease monitoring. Moreover, some alterations can be used for targeted treatment. Therefore, these advances in lymphoma molecular diagnostics in some cases have led to changes in treatment algorithms. Here, we give an overview of and discuss advances in molecular techniques in current clinical practice, as well as highlight some of them in a clinical context.

SPARC-positive macrophages are the superior prognostic factor in the microenvironment of diffuse large B-cell lymphoma and independent of MYC rearrangement and double-/triple-hit status

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease with respect to outcome. Features of the tumor microenvironment (TME) are associated with prognosis when assessed by gene expression profiling. However, it is uncertain whether assessment of the microenvironment can add prognostic information to the most relevant and clinically well-established molecular subgroups when analyzed by immunohistochemistry (IHC).

PATIENTS AND METHODS

We carried out a histopathologic analysis of biomarkers related to TME in a very large cohort (n = 455) of DLBCL treated in prospective trials and correlated with clinicopathologic and molecular data, including chromosomal rearrangements and gene expression profiles for cell-of-origin and TME.

RESULTS

The content of PD1+, FoxP3+ and CD8+, as well as vessel density, was not associated with outcome. However, we found a low content of CD68+ macrophages to be associated with inferior progression-free survival (PFS) and overall survival (OS; P = 0.023 and 0.040, respectively) at both univariable and multivariable analyses, adjusted for the factors of the International Prognostic Index (IPI), MYC break and BCL2/MYC and BCL6/MYC double-hit status. The subgroup of PDL1+ macrophages was not associated with survival. Instead, secreted protein acidic and cysteine rich (SPARC)-positive macrophages were identified as the subtype of macrophages most associated with survival. SPARC-positive macrophages and stromal cells directly correlated with favorable PFS and OS (both, P[log rank] <0.001, P[trend] < 0.001). The association of SPARC with prognosis was independent of the factors of the IPI, MYC double-/triple-hit status, Bcl2/c-myc double expression, cell-of-origin subtype and a recently published gene expression signature [lymphoma-associated macrophage interaction signature (LAMIS)].

CONCLUSIONS

SPARC expression in the TME detected by a single IHC staining with fair-to-good interobserver reproducibility is a powerful prognostic parameter. Thus SPARC expression is a strong candidate for risk assessment in DLBCL in daily practice.

Primary central nervous system lymphoma: status and advances in diagnosis, molecular pathogenesis, and treatment

Primary central nervous system lymphoma (PCNSL) is a rare group of extra-nodal non-Hodgkin lymphoma which is confined to the central nervous system or eyes. This article aims to present a brief profile of PCNSL diagnosis and treatment in immunocompetent patients. The authors retrieved information from the PubMed database up to September 2019. The annual incidence of PCNSL increased over the last four decades. The prognosis of PCNSL has improved mainly due to the introduction and wide-spread use of high-dose methotrexate, which is now the backbone of all first-line treatment polychemotherapy regimens. Gene expression profiling and next-generation sequencing analyses have revealed mutations that induce activation of nuclear factor-κB, B cell antigen receptor, and Janus kinases/signal transducer and activator of transcription proteins signal pathways. Some novel agents are investigated in the treatment of relapsed PCNSL including immunotherapy and targeted therapy. In particular, lenalidomide and ibrutinib have demonstrated durable efficiency. Treatment of PCNSL has evolved in the last 40 years and survival outcomes have improved in most patient groups, but there is still room to improve outcome by optimizing current chemotherapy and novel agents.

Outcomes of patients with limited-stage aggressive large B-cell lymphoma with high-risk cytogenetics

There is a paucity of data regarding outcomes and response to standard therapy in patients with limited-stage (LS) agressive B-cell lymphoma (LS-ABCL) who harbor MYC rearrangement (MYC-R) with or without BCL2 and/or BCL6 rearrangements. We conducted a multicenter retrospective study of MYC-R LS-ABCL patients who received either rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), or more intensive immunochemotherapy (IIC) plus or minus consolidative involved-field radiation therapy (IFRT). One hundred four patients from 15 academic centers were included. Forty four patients (42%) received R-CHOP, of whom 52% had IFRT. Sixty patients (58%) received IIC, of whom 40% had IFRT. Overall response rate was 91% (84% complete response [CR]; 7% partial response). Patients with double-hit lymphoma (DHL; n = 40) had a lower CR rate compared with patients with MYC-R only (75% vs 98%; P = .003). CR rate was higher in the IFRT vs no-IFRT group (98% vs 72%; P < .001). Median follow-up was 3.2 years; 2-year progression-free survival (PFS) and overal survival (OS) were 78% and 86% for the entire cohort, and 74% and 81% for the DHL patients, respectively. PFS and OS were similar across treatment groups (IFRT vs no IFRT, R-CHOP vs IIC) in the entire cohort and in DHL patients. Our data provide a historical benchmark for MYC-R LS-ABCL and LS-DHL patients and show that outcomes for this population may be better than previously recognized. There was no benefit of using IIC over R-CHOP in patients with MYC-R LS-ABCL and LS-DHL.

Rituximab plus high-dose chemotherapy (MegaCHOEP) or conventional chemotherapy (CHOEP-14) in young, high-risk patients with aggressive B-cell lymphoma: 10-year follow-up of a randomised, open-label, phase 3 trial

BACKGROUND

R-MegaCHOEP was the first phase 3 study comparing high-dose chemotherapy plus rituximab followed by autologous haematopoietic stem-cell transplantation (HSCT) with conventional chemotherapy plus rituximab in first-line therapy for patients aged 60 years or younger with high-risk aggressive B-cell lymphoma. Little is known about the long-term outcomes of these patients. We aimed to evaluate the long-term efficacy and safety of conventional chemotherapy versus high-dose chemotherapy after 10 years of follow-up in the R-MegaCHOEP trial.

METHODS

In this open-label, randomised, phase 3 trial done across 61 centres in Germany, patients aged 18-60 years with newly diagnosed, high-risk (age-adjusted International Prognostic Index [IPI] 2 or 3) aggressive B-cell lymphoma were randomly assigned (1:1, using Pocock minimisation) to eight cycles of conventional chemotherapy (cyclosphosphamide, doxorubicin, vincristine, etoposide, and prednisolone) plus rituximab (R-CHOEP-14) or four cycles of high-dose chemotherapy plus rituximab followed by autologous HSCT (R-MegaCHOEP). The trial was unmasked. Patients were stratified by age-adjusted IPI factors, presence of bulky disease (tumour mass ≥7·5 cm diameter), and treatment centre. The primary endpoint was event-free survival, analysed here 10 years after randomisation. 10-year overall survival, progression-free survival, conditional survival, relapse patterns, secondary malignancies, and molecular characteristics were also analysed. All analyses were done on the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT00129090.

FINDINGS

Between March 3, 2003, and April 7, 2009, 275 patients were randomly assigned to R-CHOEP-14 (n=136) or R-MegaCHOEP (n=139). 130 patients in the R-CHOEP-14 group and 132 patients in the R-MegaCHOEP group were included in the intention-to-treat population. After a median follow-up of 9·3 years (IQR 5·1-11·1), 10-year event-free survival was 51% (95% CI 42-61) in the R-MegaCHOEP group and 57% (47-67) in the R-CHOEP-14 group (adjusted hazard ratio [HR] 1·3 [95% CI 0·9-1·8], p=0·23). 10-year progression-free survival was 59% (50-68) in the R-MegaCHOEP group and 60% (51-70) in the R-CHOEP-14 group (adjusted HR 1·1 [0·7-1·7], p=0·64). 10-year overall survival was 66% (57-76) in the R-MegaCHOEP group and 72% (63-81) in the R-CHOEP-14 group (adjusted HR 1·3 [0·8-2·1], p=0·26). Relapse occurred in 30 (16% [95% CI 11-22]) of 190 patients who had complete remission or unconfirmed complete remission; 17 (17%) of 100 patients in the R-CHOEP-14 group and 13 (14%) of 90 patients in the R-MegaCHOEP group. Seven (23%) of 30 patients had low-grade histology at relapse and had better outcomes compared with patients who relapsed with aggressive histologies. Lymphoma affected the CNS in 18 (28%) of 64 patients with treatment failure. 22 secondary malignancies were reported in the intention-to-treat population; in 12 (9%) of 127 patients in the R-CHOEP-14 group and ten (8%) of 126 patients in the R-MegaCHOEP group.

INTERPRETATION

Event-free survival and overall survival were similar between groups after 10 years of follow-up; outcomes were not improved in the R-MegaCHOEP group by high-dose chemotherapy and autologous HSCT. Patients who relapsed with aggressive histology showed a high incidence of CNS involvement and poor prognosis. For these patients, novel therapies are greatly warranted.

FUNDING

Deutsche Krebshilfe (German Cancer Aid).

Applying probability calibration to ensemble methods to predict 2-year mortality in patients with DLBCL

BACKGROUND

Under the influences of chemotherapy regimens, clinical staging, immunologic expressions and other factors, the survival rates of patients with diffuse large B-cell lymphoma (DLBCL) are different. The accurate prediction of mortality hazards is key to precision medicine, which can help clinicians make optimal therapeutic decisions to extend the survival times of individual patients with DLBCL. Thus, we have developed a predictive model to predict the mortality hazard of DLBCL patients within 2 years of treatment.

METHODS

We evaluated 406 patients with DLBCL and collected 17 variables from each patient. The predictive variables were selected by the Cox model, the logistic model and the random forest algorithm. Five classifiers were chosen as the base models for ensemble learning: the naïve Bayes, logistic regression, random forest, support vector machine and feedforward neural network models. We first calibrated the biased outputs from the five base models by using probability calibration methods (including shape-restricted polynomial regression, Platt scaling and isotonic regression). Then, we aggregated the outputs from the various base models to predict the 2-year mortality of DLBCL patients by using three strategies (stacking, simple averaging and weighted averaging). Finally, we assessed model performance over 300 hold-out tests.

RESULTS

Gender, stage, IPI, KPS and rituximab were significant factors for predicting the deaths of DLBCL patients within 2 years of treatment. The stacking model that first calibrated the base model by shape-restricted polynomial regression performed best (AUC = 0.820, ECE = 8.983, MCE = 21.265) in all methods. In contrast, the performance of the stacking model without undergoing probability calibration is inferior (AUC = 0.806, ECE = 9.866, MCE = 24.850). In the simple averaging model and weighted averaging model, the prediction error of the ensemble model also decreased with probability calibration.

CONCLUSIONS

Among all the methods compared, the proposed model has the lowest prediction error when predicting the 2-year mortality of DLBCL patients. These promising results may indicate that our modeling strategy of applying probability calibration to ensemble learning is successful.

Low serum albumin is an independent risk factor in elderly patients with aggressive B‐cell lymphoma: Results from prospective trials of the German High‐Grade Non‐Hodgkin's Lymphoma Study Group

Serum albumin a well‐known risk factor predicting outcome in many solid tumors. We explore the role of low serum albumin (≤3.5 g/dL) as an independent risk factor in elderly patients with aggressive B‐cell lymphoma. Outcome of 429 patients treated with R‐CHOP‐14 in the RICOVER‐60 trial and available serum albumin were analyzed in this retrospective study. Of the 429 patients in the RICOVER‐60 trial, 137 (32%) had low and 292 (68%) had normal serum albumin levels (>3.5 g/dL). In the low albumin group, patients had significantly higher International Prognostic Index (IPI), bulky disease, extralymphatic involvement, and B‐symptoms. Event‐free survival (EFS) (P < .001), progression‐free survival (PFS) (P < .001), and overall survival (OS) (P < .001) were significantly inferior for patients with low compared to those with normal serum albumin. Multivariate analysis adjusted for IPI shows following Hazard ratios (HR) for low serum albumin: EFS (HR = 1.5; 95% confidance interval [CI] [1.1; 2.1], P = .009), PFS (HR = 1.7; 95% CI [1.2; 2.4], P = .001) and OS (HR = 1.6; 95% CI [1.1; 2.3], P = .006). Results were confirmed in 185 patients from the DENSE‐R‐CHOP‐14 and SMARTE‐R‐CHOP‐14 trials. In conclusion, low serum albumin is an independent risk factor in elderly patients with aggressive B‐cell lymphoma treated with R‐CHOP.

Acquired resistance to DZNep-mediated apoptosis is associated with copy number gains of AHCY in a B-cell lymphoma model

BACKGROUND

Enhancer of zeste homolog 2 (EZH2) is considered an important driver of tumor development and progression by its histone modifying capabilities. Inhibition of EZH2 activity is thought to be a potent treatment option for eligible cancer patients with an aberrant EZH2 expression profile, thus the indirect EZH2 inhibitor 3-Deazaneplanocin A (DZNep) is currently under evaluation for its clinical utility. Although DZNep blocks proliferation and induces apoptosis in different tumor types including lymphomas, acquired resistance to DZNep may limit its clinical application.

METHODS

To investigate possible mechanisms of acquired DZNep resistance in B-cell lymphomas, we generated a DZNep-resistant clone from a previously DZNep-sensitive B-cell lymphoma cell line by long-term treatment with increasing concentrations of DZNep (ranging from 200 to 2000 nM) and compared the molecular profiles of resistant and wild-type clones. This comparison was done using molecular techniques such as flow cytometry, copy number variation assay (OncoScan and TaqMan assays), fluorescence in situ hybridization, Western blot, immunohistochemistry and metabolomics analysis.

RESULTS

Whole exome sequencing did not indicate the acquisition of biologically meaningful single nucleotide variants. Analysis of copy number alterations, however, demonstrated among other acquired imbalances an amplification (about 30 times) of the S-adenosyl-L-homocysteine hydrolase (AHCY) gene in the resistant clone. AHCY is a direct target of DZNep and is critically involved in the biological methylation process, where it catalyzes the reversible hydrolysis of S-adenosyl-L-homocysteine to L-homocysteine and adenosine. The amplification of the AHCY gene is paralleled by strong overexpression of AHCY at both the transcriptional and protein level, and persists upon culturing the resistant clone in a DZNep-free medium.

CONCLUSIONS

This study reveals one possible molecular mechanism how B-cell lymphomas can acquire resistance to DZNep, and proposes AHCY as a potential biomarker for investigation during the administration of EZH2-targeted therapy with DZNep.

Upfront autologous hematopoietic stem cell transplantation for high-risk patients with double-expressor diffuse large B cell lymphoma

Although MYC and BCL2 co-expression in diffuse large B cell lymphoma (DLBCL) is associated with inferior prognosis, it remains uncertain whether upfront autologous hematopoietic stem cell transplantation (ASCT) is beneficial in this lymphoma. This study aimed to investigate whether ASCT consolidation could have a positive role for patients with MYC and BCL2 co-expression (double-expressor lymphoma, DEL). We retrospectively evaluated 67 DLBCL patients who underwent upfront ASCT following rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy. The 5-year overall survival (OS) and progression-free survival (PFS) were 82.3% and 79.2%, respectively. There were 23 (34.3%) patients with DEL and 51 (76.1%) patients with non-germinal center B cell (GCB) subtype. The 5-year OS and PFS of patients with DEL were not different from those with non-DEL (P = 0.429 and P = 0.614, respectively). No survival difference for OS and PFS was also observed between GCB and non-GCB subtypes (P = 0.950 and P = 0.901, respectively). The OS and PFS were comparable for patients with DEL and non-DEL and both GCB and non-GCB subtypes. In conclusion, MYC and BCL2 co-expression did not have a poor prognostic impact among high-risk patients with DLBCL treated with upfront ASCT regardless of molecular classification. This preliminary study suggested that the role of consolidative ASCT is needed to be evaluated in a prospective randomized clinical trial.

The clinicopathological and genetic features of ovarian diffuse large B-cell lymphoma

Ovarian lymphoma, whether a primary or secondary condition, is very rare. Little is known about its genetic aberrations. Here, we reviewed the clinical, morphological and immunohistochemical characteristics of nine ovarian diffuse large B-cell lymphoma (DLBCL) cases and performed fluorescence in situ hybridisation (FISH) analysis to detect MYC, BCL2 and BCL6 translocations. We also performed whole exome sequencing analysis to determine their genomic features compared with those of conventional extranodal DLBCL. The results showed that six of nine cases were bilateral and three cases were left-sided. Histologically, the tumour cells were homogeneous and a starry-sky pattern was very common in ovarian DLBCL (Burkitt-like). Immunohistochemically, most of the cases (7/9) were germinal centre B-cell-like (GCB) subtype, and dual expression of MYC and BCL2 was found in three cases of ovarian DLBCL. A double-hit (involving MYC and BCL6) phenotype was found in one case of ovarian DLBCL (GCB subtype). Sequencing analysis revealed that NOTCH4, NCOR2, BCL10 and CARD11 were frequently mutated both in ovarian DLBCL and conventional extranodal DLBCL. COL27A1, PRKCB, HLA-A, NOTCH3 and HDAC4 mutations were found only in ovarian DLBCL but not in conventional DLBCL, and NOTCH3 and HDAC4 mutations were only identified in the GCB subtype. Furthermore, several signalling pathways including the B-cell receptor, Epstein-Barr virus infection, HTLV-1 infection, Notch, PI3K-AKT and mTOR were found to be involved in ovarian DLBCL. Our results broaden the understanding of the clinicopathological and molecular characteristics of ovarian DLBCL and compare their genetic features to those of conventional extranodal DLBCL for the first time.

A novel lymphoma-associated macrophage interaction signature (LAMIS) provides robust risk prognostication in diffuse large B-cell lymphoma clinical trial cohorts of the DSHNHL

Diffuse large B-cell lymphoma (DLBCL) is a disease with heterogeneous outcome. Stromal signatures have been correlated to survival in DLBCL. Their use, however, is hampered by the lack of assays for formalin-fixed paraffin-embedded material (FFPE). We constructed a lymphoma-associated macrophage interaction signature (LAMIS) interrogating features of the microenvironment using a NanoString assay applicable to FFPE. The clinical impact of the signature could be validated in a cohort of 466 patients enrolled in prospective clinical trials of the German High-Grade Non-Hodgkin Lymphoma Study Group (DSHNHL). Patients with high expression of the signature (LAMIS^high) had shorter EFS, PFS, and OS. Multivariate analyses revealed independence from IPI factors in EFS (HR 1.7, 95% CI 1.2-2.4, p-value = 0.001), PFS (HR 1.8, 95% CI 1.2-2.5, p-value = 0.001) and OS (HR 1.8, 95% CI 1.3-2.7, p-value = 0.001). Multivariate analyses adjusted for the IPI factors showed the signature to be independent from COO, MYC rearrangements and double expresser status (DE). LAMIS^high and simultaneous DE status characterized a patient subgroup with dismal prognosis and early relapse. Our data underline the importance of the microenvironment in prognosis. Combined analysis of stromal features, the IPI and DE may provide a new rationale for targeted therapy.

DZNep-mediated apoptosis in B-cell lymphoma is independent of the lymphoma type, EZH2 mutation status and MYC, BCL2 or BCL6 translocations

Enhancer of zeste homolog 2 (EZH2) tri-methylates histone 3 at position lysine 27 (H3K27me3). Overexpression and gain-of-function mutations in EZH2 are regarded as oncogenic drivers in lymphoma and other malignancies due to the silencing of tumor suppressors and differentiation genes. EZH2 inhibition is sought to represent a good strategy for tumor therapy. In this study, we treated Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) cell lines with 3-deazaneplanocin—A (DZNep), an indirect EZH2 inhibitor which possesses anticancer properties both in-vitro and in-vivo. We aimed to address the impact of the lymphoma type, EZH2 mutation status, as well as MYC, BCL2 and BCL6 translocations on the sensitivity of the lymphoma cell lines to DZNep-mediated apoptosis. We show that DZNep inhibits proliferation and induces apoptosis of these cell lines independent of the type of lymphoma, the EZH2 mutation status and the MYC, BCL2 and BCL6 rearrangement status. Furthermore, DZNep induced a much stronger apoptosis in majority of these cell lines at a lower concentration, and within a shorter period when compared with EPZ-6438, a direct EZH2 inhibitor currently in phase II clinical trials. Apoptosis induction by DZNep was both concentration-dependent and time-dependent, and was associated with the inhibition of EZH2 and subsequent downregulation of H3K27me3 in DZNep-sensitive cell lines. Although EZH2, MYC, BCL2 and BCL6 are important prognostic biomarkers for lymphomas, our study shows that they poorly influence the sensitivity of lymphoma cell lines to DZNep-mediated apoptosis.

[Revised version of the 4th edition of the WHO classification of malignant lymphomas : What is new?]

After 8 years, the WHO has now published the updated version of the 4th edition of the classification of hematopoietic and lymphoid tumors. This update provides a conceptual rewrite of existing entities as well as some new provisional entities and categories, particularly among the aggressive B‑cell lymphomas. Important new diagnostic categories include the high-grade B‑cell lymphomas, the large B‑cell lymphoma with IRF4 rearrangement, and the Burkitt-like lymphoma with 11q aberrations. Of particular importance, new concepts concerning the taxonomy and classification of early lymphoid lesions or precursor lesions are included, such as the in situ follicular neoplasia or the in situ mantle cell neoplasia. In addition, the concept of indolent lymphoproliferations, such as breast-implant-associated anaplastic large cell lymphoma and the indolent T‑cell lymphoproliferative disorder of the gastrointestinal tract, has been strengthened. Finally, diagnostic criteria for existing lymphoma entities have been refined.

High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements with diffuse large B-cell lymphoma morphology

High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements (HGBL-DH/TH) is a newly defined entity in the latest World Health Organization Classification. Accurate diagnosis would appear to mandate fluorescence in situ hybridization (FISH) for all tumors with diffuse large B-cell lymphoma (DLBCL) morphology. We present the results of FISH, cell-of-origin, and immunohistochemistry (IHC) testing from 1228 DLBCL biopsies from 3 clinical trials and a population-based registry. HGBL-DH/TH made up 7.9% of the DLBCL, confined primarily to the germinal center B-cell-like (GCB; 13.3%) compared with activated B-cell-like (ABC; 1.7%) subtype (P < .001). HGBL-DH/TH with BCL2 rearrangement is a GCB phenomenon with no cases observed in 415 ABC DLBCL. A screening strategy restricting FISH testing to tumors of GCB subtype (by Lymph2Cx or Hans IHC) plus dual protein expression of MYC and BCL2 by IHC could limit testing to 11% to 14% of tumors, with a positive predictive value of 30% to 37%; however, this strategy would miss approximately one-quarter of tumors with HBGL-DH/TH with BCL2 rearrangement and one-third of all HGBL-DH/TH. These results provide accurate estimation of the proportion of HGBL-DH/TH among tumors with DLBCL morphology and allow determination of the impact of various methods available to screen DLBCL tumors for FISH testing.

[Aggressive B‑cell lymphomas : Recommendations from the German Panel of Reference Pathologists in the Competence Network on Malignant Lymphomas on diagnostic procedures according to the current WHO classification, update 2017]

The update of the 4th edition of the WHO classification for hematopoietic neoplasms introduces changes in the field of mature aggressive B‑cell lymphomas that are relevant to diagnostic pathologists. In daily practice, the question arises of which analysis should be performed when diagnosing the most common lymphoma entity, diffuse large B‑cell lymphoma. We discuss the importance of the cell of origin, the analysis of MYC translocations, and the delineation of the new WHO entities of high-grade B‑cell lymphomas.

Clinicopathological analysis of polyploid diffuse large B-cell lymphoma

Polyploid chromosomes are those with more than two sets of homologous chromosomes. Polyploid chromosomal abnormalities are observed in various malignant tumors. The prognosis in such cases is generally poor. However, there are no studies examining the prognosis of diffuse large B-cell lymphoma (DLBCL) with polyploid chromosomal abnormalities. Therefore, we statistically compared the clinicopathological features between polyploid DLBCL and DLBCL without polyploid abnormalities. Herein, 51 polyploid DLBCL and 53 control (without polyploid chromosomal abnormalities) cases were examined. G-banding method was employed to define polyploidy by cytogenetic analysis. Subsequently, flow cytometric immunophenotyping and immunohistochemical staining were performed. Polyploid DLBCL was defined as DLBCL with either near-tetraploid or greater number of chromosomes, as detected by the G-band. In a survival analysis, a significantly worse overall survival (OS) was observed for polyploid DLBCL (p = 0.04; p = 0.02 in cases who received R-CHOP regimens). In a multivariate analysis of OS, polyploid chromosomal abnormalities were an independent prognostic factor. Our results suggest that polyploid chromosomal abnormalities detected through G-band may represent a new poor prognostic factor for DLBCL.

BCL2 expression but not MYC and BCL2 coexpression predicts survival in elderly patients with diffuse large B-cell lymphoma independently of cell of origin in the phase 3 LNH03-6B trial

Background

Our aim was to evaluate whether the cell of origin (COO) as defined by the Hans algorithm and MYC/BCL2 coexpression, which are the two main biological risk factors in elderly patients treated with rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine, and prednisolone (R-CHOP), maintain their prognostic value in a large prospective clinical trial.

Patients and methods

We evaluated 285 paraffin-embedded samples from patients (60-80 years of age) enrolled in the Lymphoma Study Association trial LNH03-6B who were treated with R-CHOP. We correlated the COO defined by the transcriptome according to the Wright algorithm with that defined by the Hans algorithm in a subset of 62 tumors with available frozen tissue samples.

Results

The non-germinal center B-cell-like phenotype according to the Hans algorithm and BCL2 expression (but not MYC and BCL2 coexpression) predicted worse progression-free survival [hazard ratio (HR)=1.78, P = 0.003 and HR = 1.79, P = 0.003, respectively] and overall survival (HR = 1.85, P = 0.005 and HR = 1.67, P = 0.02, respectively) independently of the International Prognostic Index. The correlation between the Hans algorithm and the Wright algorithm was 91%, with an almost perfect concordance according to a kappa test (0.81).

Conclusions

Our results suggest that immunohistochemically defined COO remains a useful tool for predicting prognosis in diffuse large B-cell lymphoma when performed under optimized standardized conditions and that BCL2 expression may help to identify elderly patients at risk for relapse and who could potentially respond to anti-BCL2 targeted agents. In this prospective phase III trial, the coexpression of MYC and BCL2 does not appear to predict worse survival.

Clinical trial Number

NCT00144755.

A strong host response and lack of MYC expression are characteristic for diffuse large B cell lymphoma transformed from nodular lymphocyte predominant Hodgkin lymphoma

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is an indolent lymphoma, but can transform into diffuse large B cell lymphoma (DLBCL), showing a more aggressive clinical behavior. Little is known about these cases on the molecular level. Therefore, the aim of the present study was to characterize DLBCL transformed from NLPHL (LP-DLBCL) by gene expression profiling (GEP). GEP revealed an inflammatory signature pinpointing to a specific host response. In a coculture model resembling this host response, DEV tumor cells showed an impaired growth behavior. Mechanisms involved in the reduced tumor cell proliferation included a downregulation of MYC and its target genes. Lack of MYC expression was also confirmed in 12/16 LP-DLBCL by immunohistochemistry. Furthermore, CD274/PD-L1 was upregulated in DEV tumor cells after coculture with T cells or monocytes and its expression was validated in 12/19 cases of LP-DLBCL. Thereby, our data provide new insights into the pathogenesis of LP-DLBCL and an explanation for the relatively low tumor cell content. Moreover, the findings suggest that treatment of these patients with immune checkpoint inhibitors may enhance an already ongoing host response in these patients.

Clinicopathological Analysis of 320 Cases of Diffuse Large B-cell Lymphoma Using the Hans Classifier

The estimation of clinical prognosis for diffuse large B-cell lymphoma (DLBCL) with a quick, cost-efficient method is necessary because of the clinical heterogeneity of this disease, which leads to death, relapsed or refractory disease in approximately 40% of patients. We analyzed 320 cases diagnosed from 2007 to 2013 treated with R-CHOP therapy at Tokai University Hospital and associated institutions. DLBCL was classified according to the cell-of-origin using the Hans algorithm [germinal center B-cell-like (GCB) vs non-GCB subtypes], and into 6 subgroups derived from combinations of CD10, BCL6 and MUM1 markers. The percentage of GCB and non-GCB (NGCB) subtypes was 35% and 65%, respectively. GCB-DLBCL was characterized by lower BCL2 immunohistochemical expression, extranodal sites ＜1, better therapeutic response, and favorable overall survival (OS) and progression free survival (PFS) (P＜0.01). The most frequent subgroup was NGCB-1 (CD10^-BCL6⁺MUM1⁺, 51%) followed by GCB-1 (CD10⁺BCL6^+or-MUM1⁺, 21%), NGCB-2 (CD10^-BCL6^-MUM1⁺, 13%), GCB-2 (CD10⁺BCL6^+or-MUM1^-, 10%), GCB-3 (CD10^-BCL6⁺MUM1^-, 4%) and NGCB-3 (CD10^-BCL6^-MUM1^-, 2%). In comparison with GCB-2 and GCB-3 (both MUM1^-), the GCB-1 (MUM1⁺) was characterized by favorable PFS (5-year PFS 84% vs 65%, OR 0.368, P＜0.05), independent of high LDH (associated with unfavorable PFS, OR 7.04, P＜0.01) in the multivariate analysis. This predictive value of MUM1 was independent of CD10. Interestingly, triple-negative NGCB-3 tended to have a more favorable prognosis than the other NGCB subgroups. In conclusion, the Hans classifier is a valid method to evaluate the prognosis of DLBCL NOS. In the GCB subtypes, GCB subtypes, MUM1-positivity is associated with a more favorable outcome (PFS).

Age and Sex in Non-Hodgkin Lymphoma Therapy: It's Not All Created Equal, or Is It?

Age is the most prominent factor for survival in all patients diagnosed with lymphoma, and male sex implies an increased and independent risk for a worse progression-free survival (PFS) and overall survival (OS) in most lymphomas, possibly with the exception of mantle cell lymphoma (MCL). The worse outcome for elderly patients is only partially explained by decreased tolerance to treatment regimens associated with the increasing number and severity of comorbidities. Little is known about specific differences in lymphoma biology with respect to age and sex, and this is changing only slowly despite the recent rise in interest about these issues. To better understand the differences and their underlying mechanisms, questions of age- and sex-specific outcomes, their correlation with pharmacokinetic data, and planned and received doses, must be addressed and reported in prospective clinical trials. Such studies must be accompanied by translational research that investigates biologic differences of lymphomas between old and young and male and female patients by addressing the microenvironment, cytogenetics including next-generation sequencing and systems biology of lymphomas, and correlation of these findings with treatment results. This knowledge will enable us to adjust lymphoma treatment to the necessities of more personalized medicine.

Real world data on young patients with high-risk diffuse large B-cell lymphoma treated with R-CHOP or R-CHOEP - MYC, BCL2 and BCL6 as prognostic biomarkers

Background

Double expression of MYC and BCL2 proteins (DE) and double-hit MYC+BCL2/BCL6 translocations (DH) were established as important biomarkers in patients with diffuse large B-cell lymphoma (DLBCL) by the 2016 revision of the World Health Organization classification of lymphoid neoplasms. Whether this applies to the subgroup of young patients with high risk DLBCL is not known. We previously found that in a uniform retrospective population-based cohort of patients aged 18–60 years with high-risk DLBCL, the addition of etoposide to R-CHOP chemotherapy (R-CHOEP) resulted in improved survival mainly in patients with germinal center B-cell like (GCB) immunophenotype. The aim of this study was to investigate the prognostic and predictive value of DE and DH in this patient cohort.

Methods

Data on all young Danish patients diagnosed with de novo high-risk DLBCL 2004–2008 and treated with R-CHOP or R-CHOEP were obtained from the Danish Lymphoma database (n = 159). Tumor samples were available from 103 patients. MYC and BCL2 proteins were analyzed with quantitative immunohistochemistry (IHC) using different cut off values. MYC-, BCL2- and BCL6-translocations were examined with fluorescent in situ hybridization (FISH).

Results

DE with MYC>75% and BCL2>85% was an independent negative prognostic marker of progression free survival (PFS) in patients treated with R-CHOP but not R-CHOEP (p<0.001), also after exclusion of patients with DH. A predictive effect of DE for response (PFS) to R-CHOEP vs. R-CHOP was almost significant (p = 0.07). DH was not prognostic in this patient cohort.

Conclusion

In young patients with high-risk DLBCL, treatment with R-CHOEP may overcome the negative prognostic impact of DE observed in patients treated with R-CHOP.

Primary mediastinal large B-cell lymphoma: transcriptional regulation by miR-92a through FOXP1 targeting

Background

Primary mediastinal large B-cell lymphoma (PMBL) shares pathological features with diffuse large B-cell lymphoma (DLBCL), and molecular features with classical Hodgkin lymphoma (cHL). The miR-17∼92 oncogenic cluster, located at chromosome 13q31, is a region that is amplified in DLBCL.

Methods

Here we compared the expression of each member of the miR-17∼92 oncogenic cluster in samples from 40 PMBL patients versus 20 DLBCL and 20 cHL patients, and studied the target genes linked to deregulated miRNA in PMBL.

Results

We found a higher level of miR-92a in PMBL than in DLBCL, but not in cHL. A combination of in silico prediction and transcriptomic analyses enabled us to identify FOXP1 as a main miR-92a target gene in PMBL, a result so far not established. This was confirmed by 3UTR, and RNA and protein expressions in transduced cell lines. In vivo studies using the transduced cell lines in mice enabled us to demonstrate a tumor suppressor effect of miR-92a and an oncogenic effect of FOXP1.

A higher expression of miR-92a and the down-regulation of FOXP1 mRNA and protein expression were also found in human samples of PMBL, while miR-92a expression was low and FOXP1 was high in DLBCL.

Conclusions

We concluded to a post-transcriptional regulation by miR-92a through FOXP1 targeting in PMBL, with a clinico-pathological relevance for better characterisation of PMBL.

MYC is a positive regulator of choline metabolism and impedes mitophagy-dependent necroptosis in diffuse large B-cell lymphoma

The activation of oncogenes can reprogram tumor cell metabolism. Here, in diffuse large B-cell lymphoma (DLBCL), serum metabolomic analysis revealed that oncogenic MYC could induce aberrant choline metabolism by transcriptionally activating the key enzyme phosphate cytidylyltransferase 1 choline-α (PCYT1A). In B-lymphoma cells, as a consequence of PCYT1A upregulation, MYC impeded lymphoma cells undergo a mitophagy-dependent necroptosis. In DLBCL patients, overexpression of PCYT1A was in parallel with an increase in tumor MYC, as well as a decrease in serum choline metabolite phosphatidylcholine levels and an International Prognostic Index, indicating intermediate-high or high risk. Both in vitro and in vivo, lipid-lowering alkaloid berberine (BBR) exhibited an anti-lymphoma activity through inhibiting MYC-driven downstream PCYT1A expression and inducing mitophagy-dependent necroptosis. Collectively, PCYT1A was upregulated by MYC, which resulted in the induction of aberrant choline metabolism and the inhibition of B-lymphoma cell necroptosis. Referred as a biomarker for DLBCL progression, PCYT1A can be targeted by BBR, providing a potential lipid-modifying strategy in treating MYC-High lymphoma.

Favourable outcomes of poor prognosis diffuse large B-cell lymphoma patients treated with dose-dense Rituximab, high-dose Methotrexate and six cycles of CHOP-14 compared to first-line autologous transplantation

The optimal therapeutic approach for young diffuse large B-cell lymphoma (DLBCL) patients with high-intermediate and high-risk age-adjusted international prognostic index (aaIPI) remains unknown. Hereby we report a 10-year single-centre study of 63 consecutively treated patients. To optimize outcome, two approaches were carried out: Cohort 1 patients received four cycles R-CHOP-21 (rituximab, cyclophosphamide, daunorubicin, vincristine, prednisolone over 21 days) followed by first-line high-dose chemotherapy with autologous stem-cell support (HDCT-ASCT), resulting in 2-year progression-free (PFS) and overall survival (OS) of 60·6% and 67·9%. 39·4% of those patients were not transplanted upfront, mainly due to early progressive disease (24·2%). Cohort 2 patients received an early intensified protocol of six cycles of CHOP-14 (cyclophosphamide, daunorubicin, vincristine, prednisolone over 14 days) with dose-dense rituximab and high-dose methotrexate resulting in promising overall response- (93·3%) and complete remission (90%) rates and sustained survival (2-year PFS and OS: 93·3%). In an intention-to-treat analysis, 2-year PFS (60·6% vs. 93·3%, hazard ratio [HR] 7·2, P = 0·009) and OS (69·7% vs. 93·3%, HR 4·95, P = 0·038) differed significantly, in favour of the early intensified protocol (Cohort 2). In a multivariate Cox-regression model, PFS (HR 8·12, 95% confidence interval [CI] 1·83-35·9, P = 0·006) and OS (HR 5·86, 95% CI 1·28-26·8, P = 0·02) remained superior for Cohort 2 when adjusted for aaIPI3 as the most important prognostic factor. Survival of young poor-prognosis DLBCL patients appears superior after early therapy intensification.

How I treat double-hit lymphoma

These lymphomas, which occur in <10% of cases of diffuse large B-cell lymphoma, have been referred to as double-hit lymphomas (or triple-hit lymphomas if all 3 rearrangements are present). It is important to differentiate these lymphomas from the larger group of double-expressor lymphomas, which have increased expression of MYC and BCL-2 and/or BCL-6 by immunohistochemistry, by using variable cutoff percentages to define positivity. Patients with double-hit lymphomas have a poor prognosis when treated with standard chemoimmunotherapy and have increased risk of central nervous system involvement and progression. Double-hit lymphomas may arise as a consequence of the transformation of the underlying indolent lymphoma. There are no published prospective trials in double-hit lymphoma, however retrospective studies strongly suggest that aggressive induction regimens may confer a superior outcome. In this article, I review my approach to the evaluation and treatment of double-hit lymphoma, with an eye toward future clinical trials incorporating rational targeted agents into the therapeutic armamentarium.

Clinical Impact of the Cell-of-Origin Classification and the MYC/ BCL2 Dual Expresser Status in Diffuse Large B-Cell Lymphoma Treated Within Prospective Clinical Trials of the German High-Grade Non-Hodgkin's Lymphoma Study Group

Purpose To explore the prognostic impact and interdependence of the cell-of-origin (COO) classification, dual expression (DE) of MYC and BCL2 proteins, and MYC, BCL2, and BCL6 translocations in two prospectively randomized clinical trials of patients with diffuse large B-cell lymphoma (DLBCL). Patients and Methods Overall, 452 formalin-fixed paraffin-embedded samples from two prospective, randomized DLBCL trials (RICOVER-60, prospective, randomized study for patients > 60 years, all IPI groups; and R-MegaCHOEP, prospective, randomized study for patients ≤ 60 years with age-adjusted IPI 2,3) of the German High-Grade Non-Hodgkin Lymphoma Study Group were analyzed with the Lymph2Cx assay for COO classification, with immunohistochemistry for MYC and BCL2, and with fluorescent in situ hybridization for MYC, BCL2, and BCL6 rearrangements. Results COO classification was successful in 414 of 452 samples. No significant differences with respect to COO (activated B-cell [ABC]-like DLBCL v germinal center B-cell [GCB]-like DLBCL) were observed in event-free survival, progression-free survival, and overall survival in patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in the RICOVER-60 trial. Also, no differences with respect to COO were observed in multivariable analyses adjusted for International Prognostic Index factors in event-free survival (hazard ratio [HR] of ABC-like disease v GCB-like disease, 1.0; 95% CI, 0.6 to 1.6; P = .93), progression-free survival (HR, 1.1; 95% CI, 0.6 to 1.8; P = .82), and overall survival (HR, 1.0; 95% CI, 0.6 to 1.8; P = .96). Similar results were observed in the R-MegaCHOEP trial. In patients treated with R-CHOP, DE status was associated with significantly inferior survival compared with nonDE within the GCB, but not within the ABC subgroup. DE status was associated with significantly inferior outcome compared with patients with ABC-like DLBCL without DE (5-year PFS rate, 39% [95% CI,19% to 59%] v 68% [95% CI, 52% to 85%]; P = .03) and compared with patients with GCB-like DLBCL without DE. When data from patients with nonDE were analyzed separately, the outcome of patients in the ABC subgroup was inferior to that of patients in the GCB subgroup (5-year PFS rate, 68% [95% CI, 52% to 85%] v 85% [95% CI, 74% to 96%]; P = .04). Conclusion COO profiling in two prospective randomized DLBCL trials failed to identify prognostic subgroups, whereas dual expression of MYC and BCL2 was predictive of poor survival. Evaluation of prognostic or predictive biomarkers in the management of DLBCL, such as the COO, within prospective clinical trials will be important in the future.

Stratifying diffuse large B-cell lymphoma patients treated with chemoimmunotherapy: GCB/non-GCB by immunohistochemistry is still a robust and feasible marker

Diffuse large B cell lymphoma (DLBCL) is a heterogeneous group of aggressive lymphomas that can be classified into three molecular subtypes by gene expression profiling (GEP): GCB, ABC and unclassified. Immunohistochemistry-based cell of origin (COO) classification, as a surrogate for GEP, using three available immunohistochemical algorithms was evaluated in TMA-arranged tissue samples from 297 patients with de novo DLBCL treated by chemoimmunotherapy (R-CHOP and R-CHOP-like regimens). Additionally, the prognostic impacts of MYC, BCL2, IRF4 and BCL6 abnormalities detected by FISH, the relationship between the immunohistochemical COO classification and the immunohistochemical expression of MYC, BCL2 and pSTAT3 proteins and clinical data were evaluated. In our series, non-GCB DLBCL patients had significantly worse progression-free survival (PFS) and overall survival (OS), as calculated using the Choi, Visco-Young and Hans algorithms, indicating that any of these algorithms would be appropriate for identifying patients who require alternative therapies to R-CHOP. Whilst MYC abnormalities had no impact on clinical outcome in the non-GCB subtype, those patients with isolated MYC rearrangements and a GCB-DLBCL phenotype had worse PFS and therefore might benefit from novel treatment approaches.

Klotho, an anti-aging gene, acts as a tumor suppressor and inhibitor of IGF-1R signaling in diffuse large B cell lymphoma

Background

Klotho, is a transmembrane protein, performs as a circulating hormone and upstream modulator of the insulin-like growth factor-1 receptor (IGF-1R), fibroblast growth factor (FGF), and Wnt signaling pathways. These pathways are involved in the development and progression of B cell lymphoma. We aimed to explore the expression pattern and functional mechanism of Klotho in diffuse large B cell lymphoma (DLBCL).

Methods

Immunohistochemistry (IHC) and western blotting were performed to detect the expression level of Klotho in DLBCL patients and cell lines. Tumor suppressive effect of Klotho was determined by both in vitro and in vivo studies. Signaling pathway activity was assessed by western blotting.

Results

Remarkable lower expression levels of Klotho were observed in DLBCL patients and cell lines. Enforced expression of Klotho could significantly induce cell apoptosis and inhibit tumor growth in DLBCL. Upregulation of Klotho resulted in declined activation of IGF-1R signaling, accompanied with decreased phosphorylation of its downstream targets, including AKT and ERK1/2. Moreover, xenograft model treated with either Klotho overexpression vector or recombinant human Klotho administration presented restrained tumor growth and lower Ki67 staining.

Conclusions

Our findings establish that Klotho performs as a tumor suppressor and modulator of IGF-1R signaling in DLBCL. Targeting Klotho may provide novel strategies for future therapeutic intervention.

Clinical features of diffuse large B-cell lymphoma with polyploidy

Polyploidy, defined as more than two sets of homologous chromosomes, is found in a variety of malignant tumors and is thought to be related to disease pathogenesis. However, there have been no studies that have investigated polyploidy in diffuse large B-cell lymphoma (DLBCL). Here we reviewed clinicopathological features of 16 cases of DLBCL with polypoidy, which was defined as DLBCL with either near-tetraploid or greater number of chromosomes as detected by the G-band method. The frequency of polyploid DLBCL was 2.9 % (16/544), including 15 near-tetraploid and one near-pentaploid case. CD5, CD30 and EBER positive cases were 13 % (2/16), 13 % (2/16) and 6 % (1/16), respectively. Bcl2 positive cases were 75 % (12/16). The numbers of huge and multinucleated cells were higher in polyploid than in non-polyploid DLBCL (P = 0.0029 and P < 0.0001, respectively). Clinical features of polyploid DLBCL included reduced infiltration of extranodal sites (2/15, 13 %) and major lymph node infiltration. Of seven cases that received chemotherapy, six responded to treatment and survived. Our results suggest that polyploid DLBCL represents a clinicopathologically characteristic group of DLBCL. This knowledge can be useful for informing more personalized and targeted management of DLBCL patients.

The significance of FOXP1 in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of mature B-cell lymphoma. While the majority of patients are cured with immunochemotherapy incorporating the anti-CD20 monoclonal antibody rituximab (R-CHOP), relapsed and refractory patients still have a dismal prognosis. DLBCL subtypes including an aggressive activated B-cell-like (ABC) and a more favorable prognosis germinal center-like (GCB) DLBCL have been identified by gene expression profiling and are characterized by distinct genetic abnormalities and oncogenic pathways. This identification of novel molecular targets is now enabling clinical trials to evaluate more effective personalized approaches to DLBCL therapy. The forkhead transcription factor FOXP1 is highly expressed in the ABC-DLBCL gene signature and has been extensively studied within the context of DLBCL for more than a decade. Here, we review the significance of FOXP1 in the pathogenesis of DLBCL, summarizing data supporting its utility as a prognostic and subtyping marker, its targeting by genetic aberrations, the importance of specific isoforms, and emerging data demonstrating a functional role in lymphoma biology. FOXP1 is one of the critical transcription factors whose deregulated expression makes important contributions to DLBCL pathogenesis. Thus, FOXP1 warrants further study as a potential theranostic in ABC-DLBCL.

Recent Advances in Aggressive Large B-cell Lymphomas: A Comprehensive Review

Diffuse large B-cell lymphoma (DLBCL) is an aggressive disease with considerable heterogeneity reflected in the 2008 World Health Organization classification. In recent years, genome-wide assessment of genetic and epigenetic alterations has shed light upon distinct molecular subsets linked to dysregulation of specific genes or pathways. Besides fostering our knowledge regarding the molecular complexity of DLBCL types, these studies have unraveled previously unappreciated genetic lesions, which may be exploited for prognostic and therapeutic purposes. Following the last World Health Organization classification, we have witnessed the emergence of new variants of specific DLBCL entities, such as CD30 DLBCL, human immunodeficiency virus-related and age-related variants of plasmablastic lymphoma, and EBV DLBCL arising in young patients. In this review, we will present an update on the clinical, pathologic, and molecular features of DLBCL incorporating recently gained information with respect to their pathobiology and prognosis. We will emphasize the distinctive features of newly described or emerging variants and highlight advances in our understanding of entities presenting a diagnostic challenge, such as T-cell/histiocyte-rich large B-cell lmphoma and unclassifiable large B-cell lymphomas. Furthermore, we will discuss recent advances in the genomic characterization of DLBCL, as they may relate to prognostication and tailored therapeutic intervention. The information presented in this review derives from English language publications appearing in PubMed throughout December 2015. For a complete outline of this paper, please visit: http://links.lww.com/PAP/A12.

Comprehensive Assessment and Classification of High-Grade B-cell Lymphomas

High-grade B-cell lymphomas (HGBCLs) are a heterogeneous group of neoplasms that include subsets of diffuse large B-cell lymphoma, Burkitt lymphoma, and lymphomas with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma. Morphologically indistinguishable HGBCLs may demonstrate variable clinical courses and responses to therapy. The morphologic evaluation and classification of these neoplasms must be followed by further genetic and immunophenotypic work-up. These additional diagnostic modalities lead to a comprehensive stratification of HGBCL that determines the prognosis and optimal therapy. This article reviews the well-established and emerging biomarkers that are most relevant to the clinical management of HGBCL.

Impact of Single or Combined Genomic Alterations of TP53, MYC, and BCL2 on Survival of Patients With Diffuse Large B-Cell Lymphomas: A Retrospective Cohort Study

MYC and BCL2 translocations as well as TP53 deletion/mutation are known risk factors in diffuse large B-cell lymphoma (DLBCL) but their interplay is not well understood.In this retrospective cohort study, we evaluated the combined prognostic impact of TP53 deletion and mutation status, MYC and BCL2 genomic breaks in tumor samples of 101 DLBCL patients. The cohort included 53 cases with MYC rearrangements (MYC+).TP53 deletions/mutations (TP53+) were found in 32 of 101 lymphomas and were equally distributed between MYC+ and MYC- cases (35.8% vs. 27.1%). TP53+ lymphomas had lower responses to treatment than TP53- (complete remission 34.4% vs. 60.9%; P = 0.01). TP53 alteration was the dominant independent prognostic factor in multivariate analysis (P = 0.01). Overall survival (OS) varied considerably between subgroups with different genomic alterations: Patients with sole MYC translocation, and interestingly, with triple MYC+/BCL2+/TP53+ aberration had favorable outcomes (median OS not reached) similar to patients without genomic alterations (median OS 65 months). In contrast, patients with MYC+/BCL2+/TP53- double-hit lymphomas (DHL) (28 months), MYC+/BCL2-/TP53+ lymphomas (10 months) or sole TP53 mutation/deletion (12 months) had a poor median OS. Our findings demonstrate differences in OS of DLBCL patients depending on absence or presence of single or combined genetic alterations of MYC, BCL2, and TP53. Cooccurrence of TP53 and BCL2 aberrations ameliorated the poor prognostic impact of single TP53+ or BCL2+ in MYC positive patients.This pilot study generates evidence for the complex interplay between the alterations of genetic pathways in DLBCL, which goes beyond the concept of DHL. The variable survival of DLBCL patients dependent on single or combined alterations in the TP53, MYC, and BCL2 genes indicates the need for comprehensive genomic diagnosis.

Clinical features, tumor biology, and prognosis associated with MYC rearrangement and Myc overexpression in diffuse large B-cell lymphoma patients treated with rituximab-CHOP

MYC dysregulation, including MYC gene rearrangement and Myc protein overexpression, is of increasing clinical importance in diffuse large B-cell lymphoma (DLBCL). However, the roles of MYC and the relative importance of rearrangement vs overexpression remain to be refined. Gaining knowledge about the tumor biology associated with MYC dysregulation is important to understand the roles of MYC and MYC-associated biology in lymphomagenesis. In this study, we determined MYC rearrangement status (n=344) and Myc expression (n=535) in a well-characterized DLBCL cohort, individually assessed the clinical and pathobiological features of patients with MYC rearrangement and Myc protein overexpression, and analyzed the prognosis and gene expression profiling signatures associated with these MYC abnormalities in germinal center B-cell-like and activated B-cell-like DLBCL. Our results showed that the prognostic importance of MYC rearrangement vs Myc overexpression is significantly different in germinal center B-cell-like vs activated B-cell-like DLBCL. In germinal center B-cell-like DLBCL, MYC-rearranged germinal center B-cell-like DLBCL patients with Myc overexpression significantly contributed to the clinical, biological, and prognostic characteristics of the overall Myc-overexpressing germinal center B-cell-like DLBCL group. In contrast, in activated B-cell-like DLBCL, the occurrence, clinical and biological features, and prognosis of Myc overexpression were independent of MYC rearrangement. High Myc levels and Myc-independent mechanisms, either tumor cell intrinsic or related to tumor microenvironment, conferred significantly worse survival to MYC-rearranged germinal center B-cell-like DLBCL patients, even among Myc(high)Bcl-2(high) DLBCL patients. This study provides new insight into the tumor biology and prognostic effects associated with MYC dysregulation and suggest that detection of both MYC translocations and evaluation of Myc and Bcl-2 expression is necessary to predict the prognosis of DLBCL patients.

Impact of oncogene rearrangement patterns on outcomes in patients with double-hit non-Hodgkin lymphoma

BACKGROUND

Double-hit lymphomas (DHLs) are collectively defined as B-cell non-Hodgkin lymphomas harboring rearrangements of MYC as well as B-cell lymphoma 2 (BCL2) and/or B-cell lymphoma 6 (BCL6). To the authors' knowledge, the impact of specific oncogene rearrangements on outcomes of patients with DHL who are treated with immunochemotherapy has not been previously described.

METHODS

The authors identified patients whose diagnostic tissue specimens underwent metaphase karyotyping or fluorescence in situ hybridization for MYC as well as both BCL2 and BCL6 rearrangements. Cohorts were defined by the presence (+) or absence (-) of rearrangements: MYC+/BCL2+/BCL6- (BCL2-DHL), MYC+/BCL2-/BCL6+ (BCL6-DHL), and MYC+/BCL2+/BCL6+ (triple-hit lymphoma; THL).

RESULTS

A total of 117 patients were included in the current analysis (76 BCL2-DHL patients, 16 BCL6-DHL patients, and 25 THL patients). Compared with patients with BCL2-DHL, those with BCL6-DHL were more likely to be classified as having a non-germinal center cell of origin, presented with extranodal disease, and appeared to achieve higher rates of complete response despite receiving intensive induction therapy less frequently. However, patients with BCL6-DHL experienced a shorter median overall survival if achieving an initial complete response compared with patients with BCL2-DHL. Patients with THL experienced survival outcomes similar to those of patients with BCL2-DHL.

CONCLUSIONS

Recognition of the specific oncogene rearrangements may be of prognostic value and potentially guide future therapeutic strategies for patients with DHL.

Clinical and pathological features of Burkitt lymphoma showing expression of BCL2--an analysis including gene expression in formalin-fixed paraffin-embedded tissue

The differential diagnosis between Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) can be challenging. BL has been reported to express less BCL2 than DLBCL, but this issue has not been analysed systematically. BL expressing BCL2 can be considered to be MYC/BCL2 co-expressors, a feature that is associated with poorer outcome in DLBCL but that has not been correlated with outcome in BL so far. We analysed the expression of BCL2 in 150 cases of conventionally diagnosed BL using two different BCL2 antibodies. BCL2 expression was detected in 23% of the cases, though the expression varied in intensity and number of positive cells. We did not detect any relevant differences in clinical presentation and outcome between BCL2-positive and BCL2-negative BL in a subgroup of 43 cases for which detailed clinical data were available. An independent cohort of 17 BL with expression of BCL2 were analysed molecularly, with 13 of 17 cases classified as molecularly defined BL (Burkitt Lymphoma) using gene expression profiling on formalin-fixed paraffin-embedded tissues. The four lymphomas diagnosed molecularly as intermediates did not differ in clinical presentation and outcome from molecularly defined BL.