Impact of treatment variability and clinicopathological characteristics on survival in patients with Epstein-Barr-Virus positive diffuse large B cell lymphoma

EBV-positive diffuse large B-cell lymphoma, not otherwise specified: 2024 update on the diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Epstein Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) is an aggressive B-cell lymphoma associated with EBV infection included in the WHO classification of lymphoid neoplasms since 2016. Although historically associated to poor prognosis, outcomes seem to have improved in the era of chemoimmunotherapy.

DIAGNOSIS

The diagnosis is established through meticulous pathological evaluation. Detection of EBV-encoded RNA (EBER) is the standard diagnostic method. The ICC 2022 specifies EBV+ DLBCL, NOS as occurring when >80% of malignant cells express EBER, whereas the WHO-HAEM5 emphasizes that the majority of tumor cells should be EBER positive without setting a defined threshold. The differential diagnosis includes plasmablastic lymphoma, DLBCL associated with chronic inflammation, primary effusion lymphoma, among others.

RISK-STRATIFICATION

The International Prognostic Index (IPI) and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 and PD-1/PD-L1 are emerging as potential adverse but targetable biomarkers.

MANAGEMENT

Patients with EBV+ DLBCL, NOS, should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. EBV+ DLBCL, NOS, however, might have a worse prognosis than EBV-negative DLBCL in the era of chemoimmunotherapy. Therefore, inclusion of patients in clinical trials when available is recommended. There is an opportunity to study and develop targeted therapy in the management of patients with EBV+ DLBCL, NOS.

Update: The molecular spectrum of virus-associated high-grade B-cell non-Hodgkin lymphomas

The vast spectrum of aggressive B-cell non-Hodgkin neoplasms (B-NHL) encompasses several infrequent entities occurring in association with viral infections, posing diagnostic challenges for practitioners. In the emerging era of precision oncology, the molecular characterization of malignancies has acquired paramount significance. The pathophysiological comprehension of specific entities and the identification of targeted therapeutic options have seen rapid development. However, owing to their rarity, not all entities have undergone exhaustive molecular characterization. Considerable heterogeneity exists in the extant body of work, both in terms of employed methodologies and the scale of cases studied. Presently, therapeutic strategies are predominantly derived from observations in diffuse large B-cell lymphoma (DLBCL), the most prevalent subset of aggressive B-NHL. Ongoing investigations into the molecular profiles of these uncommon virus-associated entities are progressively facilitating a clearer distinction from DLBCL, ultimately paving the way towards individualized therapeutic approaches. This review consolidates the current molecular insights into aggressive and virus-associated B-NHL, taking into consideration the recently updated 5th edition of the WHO classification of hematolymphoid tumors (WHO-5HAEM) and the International Consensus Classification (ICC). Additionally, potential therapeutically targetable susceptibilities are highlighted, offering a comprehensive overview of the present scientific landscape in the field.

Comparison of genomic alterations in Epstein-Barr virus-positive and Epstein-Barr virus-negative diffuse large B-cell lymphoma

BACKGROUND

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (EBV-posDLBCL) is an aggressive B-cell lymphoma that often presents similar morphological and immune phenotype features to that of EBV-negative DLBCL (EBV-negDLBCL).

AIMS AND METHODS

To better understand their difference in genomic landscape, we performed whole-exome sequencing (WES) of EBV-posDLBCL and EBV-negDLBCL.

RESULTS

This analysis revealed a new mutational signature 17 (unknown) and signature 29 (smoking) in EBV-posDLBCL as well as a specific mutational signature 24 (associated with aflatoxin) in EBV-negDLBCL. Compared with EBV-negDLBCL, more somatic copy number alterations (CNAs) and deletions were detected in EBV-posDLBCL (p = 0.01). The most frequent CNAs specifically detected in EBV-posDLBCL were gains at 9p24.1 (PDL1 and JAK2), 8q22.2-q24.23 (DEPTOR and MYC), and 7q31.31-q32.2 (MET), which were validated in additional EBV-posDLBCL cases. Overall, 53.7% (22/41) and 62.9% (22/35) of the cases expressed PD-L1 and c-MET, respectively, in neoplastic cells, whereas only 15.4% (4/26) expressed c-MYC. Neoplastic c-MET expression was positively correlated with PD-L1 (p < 0.001) and MYC expression (p = 0.016). However, EBV-posDLBCL cases did not show any differences in overall survival between PD-L1-, c-MET-, or c-MYC-positive and -negative cases or between age-related groups. Analysis of the association between somatic mutation load and EBV status showed no difference in the distribution of tumor mutant burden between the two lymphomas (p = 0.41). Recurrent mutations in EBV-posDLBCL implicated several genes, including DCAF8L1, KLF2, and NOL9, while in EBV-negDLBCL, ANK2, BPTF, and CNIH3 were more frequently mutated. Additionally, PIM1 is the most altered gene in all the WES-detected cases.

CONCLUSIONS

Our results confirm that genomic alteration differs significantly between EBV-posDLBCL and EBV-negDLBCL, and reveal new genetic alterations in EBV-posDLBCL. The positive correlation of c-MET and PD-L1/c-Myc expression may be involved in the pathogenesis of EBV-posDLBCL, which is should be explored prospectively in trials involving MET-directed therapies.

The biology and treatment of Epstein-Barr virus-positive diffuse large B cell lymphoma, NOS

EBV positive Diffuse Large B-cell lymphoma, not otherwise specified (EBV+DLBCL-NOS) referred to DLBCL with expression of EBV encoded RNA in tumor nucleus. EBV+DLBCL-NOS patients present with more advanced clinical stages and frequent extranodal involvement. Although rituximab-containing immunochemotherapy regimens can significantly improve outcomes in patients with EBV+DLBCL, the best first-line treatment needs to be further explored. Due to the relatively low incidence and regional variation of EBV+DLBCL-NOS, knowledge about this particular subtype of lymphoma remains limited. Some signaling pathways was abnormally activated in EBV+DLBCL-NOS, including NF-κB and JAK/STAT pathways) and other signal transduction pathways. In addition, immune processes such as interferon response, antigen-presenting system and immune checkpoint molecule abnormalities were also observed. Currently, chimeric antigen receptor T-cell (CAR-T) therapy, chemotherapy combined with immunotherapy and novel targeted therapeutic drugs are expected to improve the prognosis of EBV+DLBCL-NOS patients, but more studies are needed to confirm this.

Dynamic changes in circulating EBV-DNA load during treatment have prognostic values in EBV+ DLBCL-NOS: a Chinese cohort study

EBV-positive diffuse large B-cell lymphoma, not otherwise specified (EBV+ DLBCL-NOS), is an EBV-positive clonal B-cell lymphoid proliferation and circulating EBV-DNA is a great indicator for prognosis among EBV associated disease. In this retrospective study, we report 66 EBV+ DLBCL cases among 2137 DLBCL-NOS cases diagnosed from 2013 to 2021 (prevalence of 6.0%). After a median follow-up of 27 months, progression-free survival (PFS) and overall survival (OS) at 2 years were 39.5% ± 6.2% and 53.6% ± 6.4%, respectively. Multivariate analysis showed that only the biomarker of the positivity of post treatment EBV-DNA had a borderline correlation with shorter PFS and OS (PFS: P = 0.053; OS: P = 0.065). Patients were divided into three subgroups according to dynamic changes of EBV-DNA status: EBV-DNA persistently negative group, EBV-DNA persistently positive group, and EBV-DNA transformed from positive to negative group; among the three groups, patients of the persistently positive group had worst PFS and OS (P = 0.0527 and P = 0.0139, respectively). Decline in EBV copies correlated significantly with treatment response as well. In conclusion, circulating EBV-DNA level played a vital role in prognostic and monitoring marker for EBV+ DLBCL-NOS.

A New Face of Fibrin-Associated Large B-Cell Lymphoma: Epstein-Barr Virus-Positive Breast Implant-Associated Diffuse Large B-Cell Lymphoma

Recently, there have been reports of what could be a new lymphoproliferative entity: breast implant-associated Epstein-Barr virus positive (EBV+) diffuse large B-cell lymphoma (EBV+ BIA-DLBCL). The new World Health Organization classification has categorized it as fibrin-associated large B-cell lymphomas (FA-LBCLs); therefore, it could be referred to as breast implant-associated fibrin-associated large B-cell lymphomas (BIA-FA-LBCLs). Although the association between breast implants and lymphomas has been known since the mid-1990s, it has been almost exclusively breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). Here, we describe the first case of BIA-FA-LBCL at our center, with a literature review of the clinical features, diagnosis and treatment approach of this lymphoma. We also explore the differential diagnosis of BIA-FA-LBCL, highlighting the diagnostic challenges and the reasons that have led these lymphomas to being labeled as a new face of FA-LBCL.

Inhibitory effect and related mechanism of decitabine combined with gemcitabine on proliferation of NK/T cell lymphoma cells

Background: EBV-associated lymphoma is a neoplasm with a poor prognosis, highly aggressive, and progressive rapidly. There is no standard clinical treatment protocol. Decitabine and gemcitabine are known to have anticancer properties against cells of various cancer, respectively. However, the effect of the combination medication on NK/T cell lymphoma cells and potential mechanisms have not been thoroughly investigated. Methods: Human NK/T cell lymphoma cells NK92MI were treated with decitabine and gemcitabine alone or in combination. Experiments, including the Cell Counting Kit-8 and flow cytometry, were performed to investigate how the combination of decitabine and gemcitabine affects the biological behavior of NK92MI cells in vitro. mRNA sequencing, RT-PCR, and western blotting were used to detect changes in the related signal pathway, mRNA, and protein expressions. Results: Decitabine and gemcitabine significantly inhibited the viability and proliferation of NK92MI cells in a dose-dependent manner. The combination index was less than 1 after treating with two drugs, which was a significant synergistic effect. The decitabine concentration with the best synergistic effect was 4.046 µM, and the gemcitabine concentration was 0.005 µM. Flow cytometry showed that combining two drugs could significantly promote apoptosis and arrest the cell cycle at the S phase. In the combined DAC and GEM group, caspase3 protein levels were higher than in either group alone or the control group. The transcriptome sequence, KEGG, and PPI analysis showed that the differential genes after combined treatment were mainly enriched in signal pathways related to cell proliferation, adhesion, and migration compared with using alone and control groups. Based on the sequencing results, we further investigated the role of DAC and GEM in ferroptosis-related signaling molecules using RT-PCR and Western blot techniques. RT-PCR and western blotting showed that the expression levels of HMOX1 and EBV cleavage gene BRLF1 were higher in the group with combined DAC and GEM than in the group alone and the control group, while the protein and mRNA expression levels of SLC7A11 were lower than the others. In addition, the GPX4 protein expression level in the combination group was lower than in the drug-alone and control groups. In addition, the combination treatment increased the ROS level of NK92MI cells. Conclusion: Our current findings suggested that decitabine had an inhibitory effect on the proliferation of NK92MI cells when co-treated with gemcitabine. This combination may increase the expression of ferroptosis-related signaling molecules, thus inhibiting the proliferation of NK92MI cells. It also promoted apoptosis in NK/T cell lymphoma. For patients with NK/T cell lymphoma, this novel combination may provide clinical benefits.

EBV-positive diffuse large B-cell lymphoma, not otherwise specified: 2022 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Epstein Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) is an entity included in the WHO classification of lymphoid neoplasms since 2016. EBV+ DLBCL, NOS, is an aggressive B-cell lymphoma associated with EBV infection, and a poor prognosis with standard chemotherapeutic approaches.

DIAGNOSIS

The diagnosis is made through a careful pathological evaluation. Detection of EBV-encoded RNA (EBER) is considered standard for diagnosis; however, a clear cutoff for percentage of positive cells has not been defined. The differential diagnosis includes plasmablastic lymphoma (PBL), DLBCL associated with chronic inflammation, primary effusion lymphoma (PEL), among others.

RISK-STRATIFICATION

The International Prognostic Index (IPI) and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 and PD-1/PD-L1 are emerging as potential adverse but targetable biomarkers.

MANAGEMENT

Patients with EBV+ DLBCL, NOS, should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. EBV+ DLBCL, NOS, however, might have a worse prognosis than EBV-negative DLBCL in the era of chemoimmunotherapy. Therefore, the inclusion of patients in clinical trials when available is recommended. There is an opportunity to study and develop targeted therapy in the management of patients with EBV+ DLBCL, NOS.

CD30+ Lymphoproliferative Disorders as Potential Candidates for CD30-Targeted Therapies

CONTEXT.—

In the early 1980s, a monoclonal antibody termed Ki-1 was developed against a cell line derived from a patient with Hodgkin lymphoma. This antibody detected a limited number of benign activated lymphocytes in lymphoid tissue, whereas in Hodgkin lymphoma it appeared to be nearly specific for Reed-Sternberg cells and their mononuclear variants. Subsequent studies showed that Ki-1 expression defined a new type of lymphoma that was later designated anaplastic large cell lymphoma with or without anaplastic large cell kinase expression/translocation. In the past 30 years, numerous new lymphoma entities have been defined, many of which are variably positive for CD30. Many virally transformed lymphoproliferative disorders are also frequently positive for CD30.

OBJECTIVE.—

To illustrate the broad spectrum of CD30+ hematologic malignancies and to provide an update of CD30-targeted therapies.

DATA SOURCES.—

Personal experiences and published works in PubMed.

CONCLUSIONS.—

Because of its low expression in normal tissue, CD30 was studied as a therapeutic target for many years. However, the first functional humanized antibody against CD30 was developed only about 10 years ago. Brentuximab vedotin is a humanized anti-CD30 antibody linked to a cytotoxin, and was approved by the US Food and Drug Administration in 2012 for treating refractory Hodgkin lymphoma and anaplastic large cell lymphoma. Since then, the list of Food and Drug Administration-approved CD30-targeted hematologic malignancies has grown. Recently, the therapies using tumor antigen-specific chimeric antigen receptor T cells targeting CD30 have incited a great deal of enthusiasm and are studied in clinical trials.

Programmed cell death-ligand 1 (PD-L1)+ tumour cells and low-reacting programmed cell death 1 (PD1)+ tumour-infiltrating lymphocytes predict poor prognosis in Epstein-Barr virus+ diffuse large B-cell lymphoma

Epstein-Barr virus (EBV)⁺ diffuse large B-cell lymphoma (DLBCL) has specific tumour cell characteristics, and these patients have worse outcomes than EBV-negative DLBCL patients. We compared 38 EBV⁺ DLBCL patients with 43 methotrexate-associated EBV⁺ B-cell lymphoproliferative disorders (MTX⁺/EBV⁺ BLPDs) and 30 non-germinal centre (GC) subtype DLBCL. Lymphoma cells of the EBV⁺ DLBCL group were positive for BCL2 in 17 patients (44.7%), CMYC in 23 patients (60.5%), and p53 in 33 patients (86.8%), which was significantly higher than in the MTX⁺/EBV⁺ BLPD group (P < 0.05), and were positive for CD30 in 29 patients (76.3%), compared with two in non-GC subtype DLBCL (6.7%) (P < 0.0001). Significantly more EBV⁺ DLBCL patients (n = 16, 42.1%) had programmed cell death-ligand 1 (PD-L1)⁺ tumour cells than patients with non-GC subtype DLBCL (n = 5, 16.7%; P = 0.024), and PD-L1⁺ tumour cells were more common in advanced stages than in early stages (P = 0.048). Twenty-five EBV⁺ DLBCL patients (69.4%) had few reactive PD1⁺ tumour-infiltrating lymphocytes (TILs), compared with 12 patients with MTX⁺/EBV⁺ BLPDs (37.5%) (P = 0.008). In the EBV⁺ DLBCL group, CD30, BCL2, CMYC, and p53 expression was not related to patient prognosis. Poor outcomes were associated with PD-L1⁺ tumour cells (P = 0.001) and low-reacting PD1⁺ TILs (P = 0.02), while their combination conferred a worse outcome (P < 0.0001). Immune evasion by PD-L1⁺ tumour cells and exhaustion of PD1⁺ TILs may occur in EBV⁺ DLBCL patients, and PD-L1/PD1 interactions may influence tumour progression and poor prognosis.

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.

Epstein-Barr Virus Positive B-Cell Lymphoproliferative Disorder of the Gastrointestinal Tract

Epstein-Barr virus positive B-cell lymphoproliferative disorder (EBV+ B-LPD) encompasses a broad clinicopathological spectrum and distinct clinical behavior that relatively favors the gastrointestinal (GI) tract. In this review, we provide an update on the clinicopathological features and biological behavior of EBV-positive mucocutaneous ulcer (EBVMCU) and primary EBV+ diffuse large B-cell lymphoma (DLBCL) of the GI tract. EBVMCU is a newly recognized entity but well known as an indolent and self-limited EBV+ B-LPD occurring in various immunodeficiencies. In contrast, EBV+ DLBCL constitutes the largest group of EBV+ B-LPDs and is regarded as an aggressive neoplasm. These two distinct diseases have historically been distinguished in the reappraisal of age-related EBV-associated B-LPDs but are challenging in routine practice regarding their differential diagnostic and therapeutic approaches. An increasing number of reports indicate that they are epidemiologically prevalent beyond western and eastern countries, but their comprehensive analysis is still limited. We also describe the PD-L1 positivity of tumorous large cells and non-malignant immune cells, which is relevant for the prognostic delineation among patients with primary DLBCL of the GI tract with and without EBV on tumor cells.

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.

Genomic insights into the pathogenesis of Epstein-Barr virus-associated diffuse large B-cell lymphoma by whole-genome and targeted amplicon sequencing

Epstein–Barr virus (EBV)-associated diffuse large B-cell lymphoma not otherwise specified (DLBCL NOS) constitute a distinct clinicopathological entity in the current World Health Organization (WHO) classification. However, its genomic features remain sparsely characterized. Here, we combine whole-genome sequencing (WGS), targeted amplicon sequencing (tNGS), and fluorescence in situ hybridization (FISH) from 47 EBV + DLBCL (NOS) cases to delineate the genomic landscape of this rare disease. Integrated WGS and tNGS analysis clearly distinguished this tumor type from EBV-negative DLBCL due to frequent mutations in ARID1A (45%), KMT2A/KMT2D (32/30%), ANKRD11 (32%), or NOTCH2 (32%). WGS uncovered structural aberrations including 6q deletions (5/8 patients), which were subsequently validated by FISH (14/32 cases). Expanding on previous reports, we identified recurrent alterations in CCR6 (15%), DAPK1 (15%), TNFRSF21 (13%), CCR7 (11%), and YY1 (6%). Lastly, functional annotation of the mutational landscape by sequential gene set enrichment and network propagation predicted an effect on the nuclear factor κB (NFκB) pathway (CSNK2A2, CARD10), IL6/JAK/STAT (SOCS1/3, STAT3), and WNT signaling (FRAT1, SFRP5) alongside aberrations in immunological processes, such as interferon response. This first comprehensive description of EBV + DLBCL (NOS) tumors substantiates the evidence of its pathobiological independence and helps stratify the molecular taxonomy of aggressive lymphomas in the effort for future therapeutic strategies.

Hemophagocytic lymphohistiocytosis associated with Epstein-Barr virus-positive diffuse large B-cell lymphoma, NOS of bone marrow-liver-spleen type: an autopsy case report

Lymphoma-associated hemophagocytic lymphohistiocytosis (HLH) has a significantly poor prognosis among secondary HLH. We describe the rare case of a 74-year-old female with secondary HLH presenting with a rapidly fatal course. Post-mortem examination revealed Epstein-Barr virus (EBV) -positive diffuse large B-cell lymphoma (DLBCL). We were unable to make a definite antemortem diagnosis because the patient did not exhibit lymphadenopathy and bone marrow biopsy demonstrated hemophagocytosis without evidence of lymphoma. She died of multiple organ failure on the twelfth day of hospitalization despite a temporary response to steroids. Autopsy revealed diffuse lymphoma cell infiltration of the bone marrow, liver and spleen, suggesting “bone marrow-liver-spleen” (BLS)-type large B-cell lymphoma (LBCL). BLS-type LBCL is a rare and clinically aggressive lymphoma, usually associated with fever, cytopenia and HLH. The disease has a high mortality rate due to the delay in diagnosis and a highly aggressive clinical course. Further studies are required to improve our understanding of this rare extranodal DLBCL.

Mutational landscape of gray zone lymphoma

The mutational landscape of gray zone lymphoma (GZL) has not yet been established, and differences from related entities are largely unknown. Here, we studied coding sequence mutations of 50 Epstein-Barr virus (EBV)-negative GZLs and 20 polymorphic EBV+ diffuse large B-cell lymphoma (DLBCL) not otherwise specified (poly-EBV-L) in comparison with classical Hodgkin lymphoma (cHL), primary mediastinal large B-cell lymphoma (PMBCL), and DLBCL. Exomes of 21 GZL and 7 poly-EBV-L cases, along with paired constitutional DNA, were analyzed as a discovery cohort, followed by targeted sequencing of 217 genes in an extension cohort of 29 GZL and 13 poly-EBV-L cases. GZL cases with thymic niche involvement (anterior mediastinal mass) exhibited a mutation profile closely resembling cHL and PMBCL, with SOCS1 (45%), B2M (45%), TNFAIP3 (35%), GNA13 (35%), LRRN3 (32%), and NFKBIA (29%) being the most recurrently mutated genes. In contrast, GZL cases without thymic niche involvement (n = 18) had a significantly distinct pattern that was enriched in mutations related to apoptosis defects (TP53 [39%], BCL2 [28%], BIRC6 [22%]) and depleted in GNA13, XPO1, or NF-κB signaling pathway mutations (TNFAIP3, NFKBIE, IKBKB, NFKBIA). They also exhibited more BCL2/BCL6 rearrangements compared with thymic GZL. Poly-EBV-L cases presented a distinct mutational profile, including STAT3 mutations and a significantly lower coding mutation load in comparison with EBV- GZL. Our study highlights characteristic mutational patterns in GZL associated with presentation in the thymic niche, suggesting a common cell of origin and disease evolution overlapping with related anterior mediastinal lymphomas.

Primary Diffuse Large B-Cell Lymphoma of the Female Urethra: A Case Report and Review of the Literature

Primary urethral non-Hodgkin's lymphoma (NHL) is uncommon. This case study reports the case of a 52-year-old woman with a light red mass at the urethral orifice. Her clinical manifestations included frequent urination, urgency, dysuria, and occasionally blood in urine. The tumor was surgically removed, and the pathological and immunohistochemistry examination confirmed the presence of a diffuse large B-cell lymphoma (DLBCL). Examination using positron emission tomography/computed tomography (PET/CT) revealed multiple hypermetabolic lymph nodes next to the external iliac vessels and bilateral inguinal regions, and focal hypermetabolic lesions in the vulvar nodules (consistent with the changes caused by lymphoma infiltration). Eight cycles of chemotherapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and dexamethasone (R-CHOP) were prescribed after surgery. Re-examination using PET/CT showed lack of hypermetabolic tumor recurrence signs, and the presence of multiple slightly large lymph nodes in the lateral iliac vessels and inguinal regions, but without significant lymph node metabolism increases. To date, only fifteen cases of primary diffuse large B-cell lymphoma of the urethra (including this one) have been reported in the literature. Therefore, we reviewed the etiology, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of DLBCL based on the existing literature to help characterize this rare disease.

EBV-positive diffuse large B-cell lymphoma, not otherwise specified: 2020 update on diagnosis, risk-stratification and management

DISEASE OVERVIEW

Epstein Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) is an entity included in the 2016 WHO classification of lymphoid neoplasms. EBV+ DLBCL, NOS, is an aggressive B-cell lymphoma associated with chronic EBV infection, and a poor prognosis with standard chemotherapeutic approaches.

DIAGNOSIS

The diagnosis is made through a careful pathological evaluation. Detection of EBV-encoded RNA (EBER) is considered standard for diagnosis; however, a clear cutoff for positivity has not been defined. The differential diagnosis includes plasmablastic lymphoma (PBL), DLBCL associated with chronic inflammation and primary effusion lymphoma (PEL), among others.

RISK-STRATIFICATION

The International Prognostic Index (IPI) and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 and PD-1/PD-L1 are emerging as potential adverse but targetable biomarkers.

MANAGEMENT

Patients with EBV+ DLBCL, NOS, should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. EBV+ DLBCL, NOS, however, might have a worse prognosis than EBV-negative DLBCL in the era of chemoimmunotherapy. There is an opportunity to study and develop targeted therapy in the management of patients with EBV+ DLBCL, NOS.