An Update on the Pathology and Molecular Features of Hodgkin Lymphoma

A Decade of Prevalence and Clinicopathological Insights Into Classical Hodgkin Lymphoma: A Study From an Indonesian Tertiary Hospital

Background Classical Hodgkin lymphoma (cHL) is a lymphoid malignancy originating from germinal center B cells, predominantly affecting young adults. The clinical profile, histologic subtypes, and immunohistochemical (IHC) patterns play crucial roles in diagnosing cHL and predicting prognosis. This study examines the prevalence, clinicopathological features, and IHC patterns of cHL at Dr. Cipto Mangunkusumo Hospital in Jakarta, Indonesia, based on large-scale data collected over a decade. Methods This retrospective analysis included 739 confirmed cases of cHL from 2014 to 2023, identified using hematoxylin and eosin staining and an IHC panel. Data on patient demographics, tumor locations, and stages were collected from medical records. The IHC markers utilized were CD20, CD3, CD30, CD15, PAX5, MUM1, Ki67, and CD45. Chi-square and Fisher exact tests were employed to analyze the distribution of subtypes across different age groups and stages. Result The most affected age group was 20-29 years, comprising 239 cases (32.34%), with a male predominance of 396 cases (53.59%). The majority of tumors were located in nodal areas, accounting for 532 cases (84.31%), while 99 cases (15.69%) were found in extranodal sites, predominantly in the mediastinum. The nodular sclerosis (NS) subtype was the most frequent, accounting for 461 cases (62.38%), followed by mixed cellularity, lymphocyte-depleted, and lymphocyte-rich classical Hodgkin lymphoma. Most cases were diagnosed at early stages (I-III), with NS significantly associated with early-stage diagnosis (OR 3.06, 95% confidence interval (CI) 1.30-7.22). Conclusion The occurrence of HL in terms of prevalence, age, gender, and stage in our study is similar to other Asian countries. Notable correlations were observed between HL subtypes with age and stage.

A proteome-wide analysis unveils a core Epstein-Barr virus antibody signature of classic Hodgkin lymphoma across ethnically diverse populations

Epstein-Barr virus (EBV) is an oncogenic virus associated with various malignancies, including classical Hodgkin lymphoma (cHL). Despite its known association, the specific role of humoral immune response to EBV remains poorly characterized in cHL. To address this, we conducted a study using a custom protein microarray to measure the antibody responses in cHL patients and matched healthy controls recruited from an East-Asian hospital-based case-control study. We identified 16 IgG antibodies significantly elevated in EBV-positive cHL compared with controls, defining an "East-Asian antibody signature of EBV-positive cHL." We evaluated responses against these 16 antibodies in a distinct European population, leveraging data from our previous European cHL case-control study from the UK, Denmark, and Sweden. A subset of antibodies (14/16, 87.5%) from the "East-Asian antibody signature of EBV-positive cHL" exhibited significant associations with cHL in the European population. Conversely, we assessed the "European antibody signature of EBV-positive cHL" identified in our prior study which consisted of 18 EBV antibodies (2 IgA, 16 IgG), in the East-Asian population. A subset of these antibodies (15/18, 83.3%) maintained significant associations with cHL in the East-Asian population. This cross-comparison of antibody signatures underscores the robust generalizability of EBV antibodies across populations. Five anti-EBV IgG antibodies (LMP-1, TK, BALF2, BDLF3, and BBLF1), found in both population-specific antibody signatures, represent a "core signature of EBV-positive cHL." Our findings suggest that the antibody responses targeting these core EBV proteins reflect a specific EBV gene expression pattern, serving as potential biomarkers for EBV-positive cHL independent of population-specific factors.

Primary Refractory Discordant Diffuse Large B-Cell and Classical Hodgkin Lymphoma

Discordant lymphomas are defined as two or more distinct pathological lymphomas occurring in the same patient. Due to the rarity of discordant lymphomas, which is due in large part to the difficulty in establishing the diagnosis, the literature is limited to small case series and case reports. Consequently, guidelines on therapeutic strategies are lacking. This article presented a case of primary refractory discordant large B-cell lymphoma and classic Hodgkin lymphoma in a young man based on cervical node and mediastinal mass biopsy, respectively. This case illustrates the difficulty in establishing the diagnosis, which ultimately warranted a high index of clinical suspicion and pursuit of multiple sequential biopsies, as well as a novel treatment strategy using an immune checkpoint inhibitor.

Circulating Tumor DNA Reflects Histologic and Clinical Characteristics of Various Lymphoma Subtypes

PURPOSE

We designed and evaluated the clinical performance of a plasma circulating tumor DNA (ctDNA) panel of 112 genes in various subtypes of lymphoma.

MATERIALS AND METHODS

Targeted deep sequencing with an error-corrected algorithm was performed in ctDNA from plasma samples that were collected before treatment in 42 lymphoma patients. Blood buffy coat was utilized as a germline control. We evaluated the targeted gene panel using mutation detection concordance on the plasma samples with matched tissue samples analyzed the mutation profiles of the ctDNA.

RESULTS

Next-generation sequencing analysis using matched tissue samples was available for 18 of the 42 patients. At least one mutation was detected in the majority of matched tissue biopsy samples (88.9%) and plasma samples (83.3%). A considerable number of mutations (40.4%) that were detected in the tissue samples were also found in the matched plasma samples. Majority of patients (21/42) were diffuse large B cell lymphoma patients. The overall detection rate of ctDNA in patients was 85.7% (36/42). The frequently mutated genes included PIM1, TET2, BCL2, KMT2D, KLHL6, HIST1H1E, and IRF8. A cutoff concentration (4,506 pg/mL) of ctDNA provided 88.9% sensitivity and 82.1% specificity to predict ctDNA mutation detection. The ctDNA concentration correlated with elevated lactate dehydrogenase level and the disease stage.

CONCLUSION

Our design panel can detect many actionable gene mutations, including those at low frequency. Therefore, liquid biopsy can be applied clinically in the evaluation of lymphoma patients, especially in aggressive lymphoma patients.

Initial Diagnosis of Classic Hodgkin Lymphoma With Skin Biopsy: A Rare Case and Review of Diagnostic Considerations

ABSTRACT

Classic Hodgkin lymphoma (CHL) is a B-cell-derived lymphoma that classically displays a bimodal age distribution. CHL typically involves the mediastinum, lymph nodes, and other visceral organs. CHL is characterized histologically by the presence of a relatively paucicellular neoplastic cell population composed of large atypical cells (including Hodgkin and Reed-Sternberg forms) in a reactive mixed inflammatory background, often with prominent necrosis. CHL rarely occurs in the skin, and the associated mixed inflammatory infiltrate or necrotic appearance can create diagnostic uncertainty. Herein, we report the case of a 31-year-old man presenting with a painful dendritic rash of the anterior chest wall with axillary lymphadenopathy. After multiple nondiagnostic biopsies that revealed largely necrotic material, a chest wall skin biopsy was obtained. The skin biopsy was diagnostic of CHL, based on the presence of large atypical dermal cells, including Hodgkin and Reed-Sternberg forms, which expressed CD15, CD30 and Fascin, in a typical mixed inflammatory and necrotic background. Through the lens of this case, we discuss the characteristics and mechanisms of skin involvement of CHL, and the histopathologic and immunohistochemical pitfalls when considering the rare diagnosis of CHL in the skin.

Unraveling the Immune Microenvironment in Classic Hodgkin Lymphoma: Prognostic and Therapeutic Implications

Classic Hodgkin lymphoma (cHL) is a lymphoid neoplasm composed of rare neoplastic Hodgkin and Reed-Sternberg (HRS) cells surrounded by a reactive tumor microenvironment (TME) with suppressive properties against anti-tumor immunity. TME is mainly composed of T cells (CD4 helper, CD8 cytotoxic and regulatory) and tumor-associated macrophages (TAMs), but the impact of these cells on the natural course of the disease is not absolutely understood. TME contributes to the immune evasion of neoplastic HRS cells through the production of various cytokines and/or the aberrant expression of immune checkpoint molecules in ways that have not been fully understood yet. Herein, we present a comprehensive review of findings regarding the cellular components and the molecular features of the immune TME in cHL, its correlation with treatment response and prognosis, as well as the potential targeting of the TME with novel therapies. Among all cells, macrophages appear to be a most appealing target for immunomodulatory therapies, based on their functional plasticity and antitumor potency.

Histone deacetylases (HDACs) as the promising immunotherapeutic targets for hematologic cancer treatment

Bone marrow transplantation is regarded as the most effective immunotherapy for hematologic cancer, but it generally faces difficulties in matching. Aberrant expression of histone deacetylases (HDACs) is closely related to the occurrence and development of hematological cancer. Recent studies suggested that HDACs might play a critical role in initiating anti-cancer immune response or enhancing anti-cancer immunotherapy. Besides, combining HDAC inhibition and immunotherapy could prevent immunotherapy resistance in some degree and reach an extended treatment window. This review summarized the relationship between HDACs and immune and described the current understanding of HDACs in immunotherapy for hematologic cancer.

Molecular Characterisation of Epstein-Barr Virus in Classical Hodgkin Lymphoma

Hodgkin lymphomas (HLs) are a heterogeneous group of lymphoid neoplasia associated with Epstein-Barr virus (EBV) infection. EBV, considered to be an important etiological co-factor in approximately 1% of human malignancies, can be classified into two genotypes based on EBNA-2, EBNA-3A and EBNA-3C sequences, and into genetic variants based on the sequence variation of the gene coding for the LMP1 protein. Here, we present the results on the distribution of EBV genotypes 1 and 2 as well as LMP1 gene variants in 50 patients with EBV-positive classical HL selected from a cohort of 289 histologically verified cases collected over a 9-year period in a tertiary clinical center in the Southeast of Europe. The population-based sequencing of the EBNA-3C gene showed the exclusive presence of EBV genotype 1 in all cHL samples. The analysis of EBV LMP1 variant distribution showed a predominance of the wild-type strain B95-8 and the Mediterranean subtype with 30 bp deletion. These findings could contribute to the understanding of EBV immunobiology in cHL as well as to the development of a prophylactic and therapeutic vaccine.

Anti-PD1 Consolidation in Patients with Hodgkin Lymphoma at High Risk of Relapse after Autologous Stem Cell Transplantation: A Multicenter Real-Life Study

(1) Background: Consolidation therapy is an emerging strategy for patients with relapsed/refractory (RR) Hodgkin Lymphoma (HL) at high risk of failing salvage autologous stem cell transplantation (ASCT). (2) Objectives: To assess the safety and effectiveness of PD1-blockade consolidation for these high-risk patients. (3) Design: Multi-center retrospective analysis. (4) Methods: We identified 26 patients given anti-PD1 consolidation, from June 2016 to May 2020. (5) Results: Patients displayed the following risk factors: refractory disease (69%), relapse < 12 months from upfront therapy (15%), ≥2 lines of salvage therapy (73%), extranodal disease (65%). Nineteen patients (73%) had ≥3 of these factors. In addition, 16 patients (61%) also displayed PET-positive (Deauville ≥ 4) disease before ASCT. Treatment-related adverse events (TRAEs), never graded > 3, occurred in 12 patients (46.15%) and mainly included skin rashes (41.7%), transaminitis (33.3%), and thyroid hypofunction (25%). Patients completed a median of 13 courses (range 6−30). At a median follow-up of 25.8 months post-ASCT, the median progression-free (PFS) was 42.6 months, with a 2-year PFS and overall survival rates of 79% and 87%, respectively. (6) Conclusions: Post-ASCT consolidation with anti-PD1 is feasible and effective. Further studies are warranted to define the optimal treatment length and patients’ subsets more likely to benefit from this approach.

The prognostic value of Epstein-Barr virus infection in Hodgkin lymphoma: A systematic review and meta-analysis

INTRODUCTION

Epstein-Barr virus (EBV) contributes significantly to the development and occurrence of B-cell lymphomas. However, the association between EBV infection status and clinical outcomes in Hodgkin lymphoma (HL) patients has long been controversial. Therefore, we aimed to estimate the prognostic significance of EBV infection in HL survival.

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library for relevant cohort studies from the date of their inception to February 20, 2022. Hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS), Failure-free survival (FFS), Progression-free survival (PFS), Event-free survival (EFS) and disease-specific survival (DSS) were extracted from the studies or calculated. Subgroup analyses were conducted independently on the five survival outcomes to investigate the source of heterogeneity.

RESULTS

A total of 42 qualified studies involving 9570 patients were identified in our meta-analysis. There was an association between EBV positivity and significantly poorer OS (HR=1.443, 95% CI: 1.250-1.666) and DSS (HR=2.312, 95% CI: 1.799-2.972). However, the presence of EBV in HL showed no effect on FFS, PFS or EFS. In subgroup analyses of OS, DSS and FFS stratified by age groups, EBV positivity was associated with poorer prognosis in elderly patients. Meanwhile, in children and adolescents with EBV-positive HL, we also observed a trend toward a better prognosis, though the results were not statistically significant.

CONCLUSIONS

EBV-positive status is associated with poor OS and DSS in HL patients. EBV infection should therefore be considered a valuable prognostic marker and risk-stratifying factor in HL, especially in older patients.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022328708.