Outcomes among North American patients with diffuse large B-cell lymphoma are independent of tumor Epstein-Barr virus positivity or immunosuppression

Large B-Cell Lymphomas in the 5th Edition of the WHO-Classification of Haematolymphoid Neoplasms-Updated Classification and New Concepts

The family/class of the large B-cell lymphomas (LBCL) in the 5th edition of the World Health Organization (WHO) classification of haematolymphoid tumors (WHO-HAEM5) features only a few major changes as compared to the 4th edition. In most entities, there are only subtle changes, many of them only representing some minor modifications in diagnostic terms. Major changes have been made in the diffuse large B-cell lymphomas (DLBCL)/high-grade B-cell lymphomas (HGBL) associated with MYC and BCL2 and/or BCL6 rearrangements. This category now consists of MYC and BCL2 rearranged cases exclusively, while the MYC/BCL6 double hit lymphomas now constitute genetic subtypes of DLBCL, not otherwise specified (NOS) or of HGBL, NOS. Other major changes are the conceptual merger of lymphomas arising in immune-privileged sites and the description of LBCL arising in the setting of immune dysregulation/deficiency. In addition, novel findings concerning underlying biological mechanisms in the pathogenesis of the different entities are provided.

TET2 and LILRB1 mutations are frequent in Epstein-Barr virus-positive diffuse large B-cell lymphoma especially in elderly patients

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) harboring Epstein-Barr virus (EBV) primarily occurs in patients who have underlying immunodeficiency or in elderly patients but is also reported in young, immunocompetent patients. The authors investigated the pathologic differences in EBV-positive DLBCL in these three groups of patients.

METHODS

In total, 57 patients with EBV-positive DLBCL were included in the study; of these, 16 patients had associated immunodeficiency, 10 were young (younger than 50 years), and 31 were elderly (aged 50 years or older). Immunostaining for CD8, CD68, PD-L1, and EBV nuclear antigen 2, and panel-based next-generation sequencing was performed on formalin-fixed, paraffin-embedded blocks.

RESULTS

Immunohistochemistry revealed EBV nuclear antigen 2 positivity in 21 of the 49 patients. The degree of CD8-positive and CD68-positive immune cell infiltration and PD-L1 expression did not differ significantly in each group. Extranodal site involvement was more common in young patients (p = .021). In mutational analysis, the genes with the highest mutation frequency were PCLO (n = 14), TET2 (n = 10), and LILRB1 (n = 10). For the TET2 gene, all 10 mutations were found in elderly patients (p = .007). Compared with a validation cohort, both TET2 and LILRB1 showed a higher mutation frequency in EBV-positive patients than in EBV-negative patients.

CONCLUSIONS

EBV-positive DLBCL occurring in three different age and immune status groups showed similar pathologic characteristics. Notably, a high frequency of TET2 and LILRB1 mutations was characteristic of this disease in elderly patients. Further studies are needed to determine the role of TET2 and LILRB1 mutations in the development of EBV-positive DLBCL along with immune senescence.

PLAIN LANGUAGE SUMMARY

Epstein-Barr virus-positive diffuse large B-cell lymphoma occurring in three different groups (immunodeficiency-associated, young, and elderly) showed similar pathologic characteristics. The frequency of TET2 and LILRB1 mutations was high in elderly patients with Epstein-Barr virus-positive diffuse large B-cell lymphoma.

B2M mutation paves the way for immune tolerance in pathogenesis of Epstein-Barr virus positive diffuse large B-cell lymphomas

This study focused genetic pathogenesis and tumor microenvironment of Epstein-Barr virus (EBV) positive diffuse large B-cell lymphomas (DLBCL) in patients without immunodeficiency. DNA samples from these cases were sequenced by next generation sequencing (NGS) using a selected gene panel. Results revealed that most gene mutations were not specific for EBV positive DLBCL. However, B2M (β2-microglobulin) mutations were significantly increased and HLA-I or HLA-II expression was decreased in these cases, which was related to patient's poor outcome. B2M mutations and deregulation of B2M expression were further confirmed by Sanger sequencing and immunohistochemistry. Reducing the infiltration of CD8+ T lymphocytes, related to decreased expression of HLA-I or HLA-II was found in these patients. These results suggest that the mutations of B2M could cause the disruption of the expression and functions of this important subunit of HLA, leading to decreased expression of HLA-I or HLA-II and subsequently to reduce T lymphocyte infiltration in tumor tissues. The consequence of this event lessens the recognition and elimination of EBV+ tumor cells by host immunity and paves the way for the host immune tolerance to EBV+ tumor cells by evading immune recognition and escaping the T lymphocyte killing.

EBV-positive high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements: a multi-institutional study

AIMS

It is unknown whether Epstein-Barr virus (EBV) infection can occur in high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements, also known as double-hit or triple-hit lymphoma (DHL/THL).

METHODS AND RESULTS

Here we report 16 cases of EBV+ DHL/THL from screening 846 cases of DHL/THL and obtaining additional EBV+ cases through multi-institutional collaboration: 8 MYC/BCL2 DHL, 6 MYC/BCL6 DHL, and 2 THL. There were 8 men and 8 women with a median age of 65 years (range, 32-86). Two patients had a history of follicular lymphoma and one had AIDS. Nine of 14 patients had an International Prognostic Index of ≥3. Half of the cases showed high-grade/Burkitt-like morphology and the other half diffuse large B-cell lymphoma morphology. By immunohistochemistry, the lymphoma cells were positive for MYC (n=14/16), BCL2 (n=12/16), BCL6 (n=14/16), CD10 (n=13/16), and MUM1 (n=6/14). By Hans algorithm, 13 cases were classified as GCB and 3 as non-GCB. The lymphomas frequently showed an EBV latency type I with a median EBV-encoded small RNAs of 80% positive cells (range, 20-100%). After a median follow-up of 36.3 months (range, 2.0-41.6), 7 patients died with a median survival of 15.4 months (range, 3.4-47.3) after diagnosis of EBV+ DHL/THL. Five of 6 patients with MYC/BCL6 DHL were alive including 4 in complete remission. In contrast, only 4/10 patients with MYC/BCL2 DHL or THL were alive including 2 in complete remission. The median survival in patients with MYC/BCL6 DHL was unreached and was 21.6 months in patients with MYC/BCL2 DHL or THL.

CONCLUSIONS

EBV infection in DHL/THL is rare (~1.5%). Cases of EBV+ DHL/THL are largely similar to their EBV-negative counterparts clinicopathologically. Our findings expand the spectrum of EBV+ B-cell lymphomas currently recognized in the WHO classification and suggest differences between EBV+ MYC/BCL2 and MYC/BCL6 DHL that may have therapeutic implications.

Clinicopathological features and survival in EBV-positive diffuse large B-cell lymphoma not otherwise specified

In this retrospective study, we report 70 cases of Epstein-Barr virus (EBV)+ diffuse large B-cell lymphoma not otherwise specified (DLBCL-NOS) among 1696 DLBCL-NOS cases diagnosed between 2006 and 2019 (prevalence of 4.1%). At diagnosis, median age was 68.5 years; 79% of the cases presented with an advanced-stage disease (III-IV), 48% with extranodal lesions, and 14% with an hemophagocytic lymphohistiocytosis (HLH) (8 at diagnosis and 1 on therapy). A total of 46 cases presented a polymorphic pattern, and 21 were monomorphic. All had a non-germinal center B phenotype, with the majority of tumor cells expressing CD30 and programmed death ligand 1 (98% and 95%, respectively). Type II and III EBV latency was seen in 88% and 12% of the cases, respectively. Patients were treated with immunochemotherapy (59%) or chemotherapy (22%), and 19% received palliative care due to advanced age and altered performance status. After a median follow-up of 48 months, progression-free survival (PFS) and overall survival (OS) at 5 years were 52.7% and 54.8%, respectively. Older age (>50 years) and HLH were associated with shorter PFS and OS in multivariate analysis (PFS: hazard ratio [HR], 14.01; 95% confidence interval [CI], 2.34-83.97; and HR, 5.78; 95% CI, 2.35-14.23; OS: HR, 12.41; 95% CI, 1.65-93.53; and HR, 6.09; 95% CI, 2.42-15.30, respectively). Finally, using a control cohort of 425 EBV- DLBCL-NOS, EBV positivity was associated with a shorter OS outcome within patients >50 years (5-year OS, 53% [95% CI, 38.2-74] vs 60.8% [95% CI, 55.4-69.3], P = .038), but not in younger patients.

Advances in the Pathogenesis of EBV-Associated Diffuse Large B Cell Lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin's lymphoma (NHL) in adults. Epstein-Barr virus (EBV) positive DLBCL of the elderly was defined by the World Health Organization (WHO) in 2008, it was restricted only to patients older than 50 years old, and it was attributed to immunesenescence associated with physiological aging. After the description of EBV-associated DLBCL in children and young adults, the WHO redefined the definition, leading to the substitution of the modifier "elderly" with "not otherwise specified" (EBV + DLBCL, NOS) in the updated classification, and it is no more considered provisional. The incidence of EBV + DLBCL, NOS varies around the world, in particular influenced by the percentage of EBV+ cells used as cut-off to define a case as EBV-associated. EBV has effect on the genetic composition of tumor cells, on survival, and at the recruitment of immune cells at the microenvironment. In this review, the role of EBV in the pathogenesis of DLBCL is discussed.

Epstein-Barr virus infection is associated with clinical characteristics and poor prognosis of multiple myeloma

The aim of the present study was to evaluate the relationship of Epstein-Barr virus (EBV) infection and multiple myeloma (MM) and its impact on clinical characteristics and prognosis. Fresh peripheral blood mononuclear cells (PBMCs) from 139 MM patients who had been diagnosed and treated from January 2010 to May 2018 and 50 PBMC samples from healthy donors were obtained. PCR was carried out for detection of EBV-DNA. The results indicated a significantly higher EBV-DNA concentration among 139 MM patients compared with healthy controls (P<0.05). Correlation analysis showed that the expression of EBV-DNA was positively correlated with the serum free light chain ratio (sFLCR) and progressive disease (PD)/relapse (P<0.05). Especially, in EBV-DNA high-expression MM patients, EBV-DNA concentration for patients with sFLCR ≥100 was higher than that of patients with sFLCR <100. EBV-DNA concentration was higher in patients with disease PD/relapse than those without disease PD/relapse. In univariate analysis, the progress free survival (PFS) was inferior in MM patients with high expression of EBV-DNA, high lactate dehydrogenase (LDH), and high-risk according to mSMART and International Myeloma Working Group (IMWG), stage III according to R-ISS staging, extramedullary lesions, and genetic changes (P<0.05). However, in multivariate analysis, LDH, poor karyotype, R-ISS staging, and mSMART were independent prognostic factors for PFS. Taken together, our studies suggest that an association exists between EBV infection and clinical characteristics of MM patients, and EBV infection appears to have a slight impact on the prognosis of MM. However, the results require further validation in other independent prospective MM cohorts.

Magnesium: The overlooked electrolyte in blood cancers?

Magnesium is an important element that has essential roles in the regulation of cell growth, division, and differentiation. Mounting evidence in the literature suggests an association between hypomagnesemia and all-cause mortality. In addition, epidemiologic studies have demonstrated that a diet poor in magnesium increases the risk of developing cancer, highlighting its importance in the field of hematology and oncology. In solid malignancies, hypomagnesemia at diagnosis portends a worse prognosis. However, little is known about prognosis in patients with hypomagnesemia and blood cancers in general; lymphoma more specifically. Hypomagnesemia has been associated with a higher viral load of the Epstein Barr virus, a virus associated with a multitude of hematologic malignancies. The role of magnesium in the immune system has been further elucidated in studies of patients with a rare primary immunodeficiency known as XMEN disease (X-linked immunodeficiency with Magnesium defect, Epstein-Barr virus (EBV) infection, and Neoplasia disease). These patients have a mutation in the MAGT1 gene, which codes for a magnesium transporter. The mutation leads to impaired T cell activation and an increased risk of developing hematologic malignancies. In this review we discuss the relevance of magnesium as an electrolyte, current measurement techniques, and the known data related to cause and prognosis of blood cancers. The goal is to use these data to stimulate additional high-quality and well powered studies to further investigate the role of magnesium in preventing cancer and improving outcomes of patients with malignancy and concomitant magnesium deficiency.

A Rare, Yet Treatable Pancreatic Tumor: Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma

BACKGROUND Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) is a rare subtype of B-cell neoplasm that can have diverse presentations. When it involves the pancreas (i.e., pancreatic lymphoma), it can mimic metastatic pancreatic adenocarcinoma. Pancreatic lymphoma and adenocarcinoma often have similar clinical, laboratory, and radiographic features making the distinction challenging without pathological tissue examination. The differentiation of these 2 entities is important as the prognosis of pancreatic lymphoma is certainly more favorable with a chance of cure with chemoimmunotherapy. CASE REPORT We present an unusual case of EBV-positive DLBCL involving the pancreas that was initially believed to be metastatic pancreatic adenocarcinoma. The patient was treated with chemoimmunotherapy and had a remarkable response. This is the first known case of EBV-positive DLBCL involving the pancreas that was successfully treated with chemoimmunotherapy. CONCLUSIONS EBV-positive DLBCL can have diverse presentations, including a pancreatic mass with multi-organ involvement, which mimics metastatic pancreatic adenocarcinoma. The prognosis of EBV-positive DLBCL is thought to be worse than that of EBV-negative tumors. However, it remains certainly superior to that of its adenocarcinoma counterpart with conventional chemoimmunotherapy.

The tumour microenvironment is immuno-tolerogenic and a principal determinant of patient outcome in EBV-positive diffuse large B-cell lymphoma

OBJECTIVE

Epstein-Barr virus-positive diffuse large B-cell lymphoma (EBV^-pos DLBCL) is a recently identified entity. Data regarding outcome to frontline immuno-chemotherapy are conflicting. Although the prognostic impact of the tumour microenvironment (TME) in EBV^-neg DLBCL is well-established, it remains untested whether the TME influences survival in EBV^-pos DLBCL. There are no data with new digital gene expression technologies that simultaneously interrogate the virus, B cells and the tumour microenvironment (TME).

METHODS

We used the NanoString™ platform in a population-based cohort of 433 patients to establish if the technology could detect EBV in the tumour biopsies and to investigate the influence that EBV has on the complex tumour microenvironment of DLBCL.

RESULTS

Incidence of EBV^-pos DLBCL was 6.9% with 5-year survival of 65% vs 82% in EBV^-neg DLBCL (P = 0.018). EBV^-pos tissues had similar expression of T-cell genes compared to EBV^-neg DLBCL but higher levels of the antigen-presenting molecule B2M. This was countered by elevated PD-L1, PD-L2, LAG3 and TIM3 immune checkpoints and a higher CD163/CD68 "M2" macrophage score.

CONCLUSION

In EBV^-pos DLBCL, the TME is immuno-tolerogenic and may explain the poor outcomes seen in this subtype of DLBCL.

History of autoimmune conditions and lymphoma prognosis

Autoimmune conditions are strong risk factors for developing lymphoma, but their role in lymphoma prognosis is less clear. In a prospective cohort study, we evaluated self-reported history of eight autoimmune conditions with outcomes in 736 diffuse large B-cell, 703 follicular, 302 marginal zone (MZL), 193 mantle cell (MCL), 297 Hodgkin lymphoma (HL), and 186 T-cell lymphomas. We calculated event-free survival (EFS) and overall survival (OS), and estimated hazard ratios (HRs) and 95% confidence intervals (CIs), adjusting for sex, prognostic score, and treatment. History of any of the eight autoimmune conditions ranged from 7.4% in HL to 18.2% in MZL, and was not associated with EFS or OS for any lymphoma subtype. However, there was a positive association of autoimmune conditions primarily mediated by B-cell responses with inferior EFS in MCL (HR = 2.23, CI: 1.15–4.34) and HL (HR = 2.63, CI: 1.04–6.63), which was largely driven by rheumatoid arthritis. Autoimmune conditions primarily mediated by T-cell responses were not found to be associated with EFS or OS in any lymphoma subtype, although there were few events for this exposure. Our results indicate that distinguishing autoimmune conditions primarily mediated by B-cell/T-cell responses may yield insight regarding the impact of this comorbid disease, affecting ~10% of lymphoma patients, on survival.

Clinical characteristics and prognostic significance of EBER positivity in diffuse large B-cell lymphoma: A meta-analysis

Recent studies show that Epstein-Barr virus (EBV) positivity might be related to adverse prognosis in patients with diffuse large B-cell lymphoma (DLBCL), but the results are still inconclusive. We conducted this meta-analysis to define the clinical value of EBV infection in DLBCL. All potential articles in PubMed, Web of Science, Medline, and Embase were retrieved. Using the random-effects or fixed-effect model, pooled hazard ratios (HRs) or relative risk (RR) with 95% confidence intervals (CIs) were used to calculate the correlation between EBER and prognosis and clinical features in DLBCL. A total of 13 qualified studies with 4111 patients were identified in our meta-analysis based on the inclusion and exclusion criteria. The overall estimates revealed that EBV-encoded small RNAs (EBER) positivity was significantly correlated with worse overall survival (HR = 2.43, 95% CI: 1.73–3.36) and progression-free survival (HR = 3.60, 95% CI: 2.07–6.26). In addition, EBER positivity was associated with age older than 60 years (RR = 1.51, 95% CI: 1.02–2.24), male sex (RR = 1.34, 95% CI: 1.05–1.71), more advanced stage (RR = 2.25, 95% CI: 1.72–2.96), high international prognostic index (RR = 2.20, 95% CI: 1.71–2.82), more than one extranodal involvement (RR = 1.69, 95% CI: 1.27–2.26), presence of B symptom (RR = 1.75, 95% CI: 1.30–2.35), non-germinal center B-cell subtype (RR = 1.35, 95% CI: 1.03–1.78), and elevated lactate dehydrogenase levels (RR = 1.30, 95% CI: 0.98–1.72). EBER positivity was correlated with worse outcomes, worse clinical course, and adverse clinicopathologic features among patients with DLBCL.