Hodgkin Reed-Sternberg-Like Cells in Non-Hodgkin Lymphoma

Comprehensive biomarker profiles in hematological malignancies: improving diagnosis, prognosis, and treatment

Hematological malignancies present substantial challenges in clinical practice due to their heterogeneity and complex biological profiles. In these diseases, biomarkers - measurable indicators of biological states - are indispensable for diagnosis, prognosis, and therapeutic decision-making. Emerging biomarkers are significantly improving outcomes in hematological cancers by enhancing early detection, refining prognostic assessments, enabling personalized treatment approaches, and optimizing overall patient management. This progress translates into better clinical outcomes and more effective strategies to treat and manage malignancies. The field of biomarker discovery has developed from basic morphological and cytogenetic markers to advanced molecular techniques, including polymerase chain reaction (PCR) and next-generation sequencing (NGS), which have significantly enhanced diagnostic accuracy and led to the development of targeted therapies. Additionally, the recent advent of technologies like mass spectrometry and single-cell RNA sequencing enables comprehensive molecular profiling and reveals novel biomarkers that were previously undetectable. Our aim in this manuscript is to provide a comprehensive overview of recent and novel immunohematological biomarkers, their diagnostic and therapeutic applications, and the future directions of this field.

Evaluation of NHL subtypes, staging, and prognostic factors: A single-centric retrospective cohort study

OBJECTIVE

The study aims to improve the diagnosis and management of non-Hodgkin's lymphoma (NHL), identify crucial prognostic factors, expand our understanding of patients, facilitate comparative analyses, and provide clear guidance for managing NHL patients. By addressing these objectives, the study provides valuable insights into the distribution of NHL subtypes, staging workup, prognostic factors, and survival patterns in the Indian population.

MATERIALS AND METHODS

This study employed a single-centric, retrospective cohort design, which was conducted from 2009 to 2014. A total of 410 participants were included with a confirmed diagnosis of NHL based on their biopsy results; the ages ranged from 4 to 91 years. Patients who missed follow-ups or did not complete the study were excluded from the survival rate analysis results.

RESULTS

The gender distribution revealed that the mean ages for male and female patients were 49.37 ± 18.9 and 49.06 ± 18.34, respectively. The majority of cases in the diffuse large B cell lymphoma (DLBCL) group were under Stage 1A (47.7) and Stage 3A (23.2%). A significant portion of DLBCL cases fell into the low intermediate risk (LIR) category (27.3%). Smaller percentages are observed in the high intermediate risk (HIR) category (17.5%) and the high-risk category (9.7%). It is observed that in patients with relapse, a significant majority of cases (77.4%) were those initially diagnosed at Stage 3 or higher. 71.1% of the cases that did not have relapse had completed chemotherapy. The median survival time, according to Kaplan-Meier survival analysis, was 24 ± 1.8 months overall.

CONCLUSION

While gender-based smoking and occupational disparities stand out, the prevalence of complete remission underscores treatment efficacy. Detecting challenges in advanced-stage diagnosis and incomplete treatments highlights the importance of timely intervention and comprehensive patient care. The absence of survival differences based on immunohistochemistry (IHC) subtypes suggests multifactorial influences on patient outcomes, motivating further investigation.

Synchronous Lymphoma: Diagnostic Challenges in a Case of Coexisting Diffuse Large B-cell Lymphoma and Classical Hodgkin Lymphoma

Synchronous lymphoma (SL) is the simultaneous occurrence of two or more unique kinds of lymphomas in the same individual at the initial diagnosis. Accurate diagnosis requires histopathological examination, immunohistochemistry (IHC), and molecular studies. We found only a handful of reported cases of SLs involving different anatomical sites in medical literature, and no large-scale studies have specifically addressed the frequency of this combination. Given the rarity of this combination, each case is often reported as a unique case study, and treatment approaches may vary depending on individual circumstances. Here, we report a case of a 60-year-old female patient presenting with pain in the abdomen, vomiting, fever, significant weight loss, and palpable inguinal nodes. Her endoscopic biopsy from the stomach revealed diffuse large B-cell lymphoma (DLBCL) while the inguinal node biopsy showed classical Hodgkin lymphoma (cHL), mixed cellularity type. Our report discusses and highlights the importance of detailed clinical history, investigations, and molecular workups that are essential to diagnosing these rare cases.

Pitfalls in the Cytological Diagnosis of Nodal Hodgkin Lymphoma

BACKGROUND

Hodgkin lymphoma (HL) is a hematopoietic neoplasm characterized by malignant Reed-Sternberg (RS) cells in an inflammatory background. Although the cytological features of HL are well elucidated in literature, yet many postulated factors cause its misdiagnosis. This study aims to assess the diagnostic reliability of fine needle aspiration cytology (FNAC) in HL and evaluate the factors contributing to a false-negative and false-positive diagnosis, taking histopathology as the gold standard.

METHODS

This was a retrospective study in which 47 cases of HL diagnosed on histopathology were compared with their prior cytological diagnosis.

RESULTS

The patient's age ranged from 3 to 80 years (median: 36 years) with a M:F ratio of 2.9:1. Lymph node aspirations were performed from multiple anatomical sites, out of which the cervical was the most common (57.8%). FNAC was inconclusive in two cases due to unsatisfactory smears. The false-negative diagnosis of reactive lymphadenitis was given in four cases, and false-positive in four cases, which included three cases of non-HL, and one case of malignant small round blue cell tumor. The overall diagnostic accuracy of FNAC in the diagnosis of HL was 82.2%.

CONCLUSIONS

The cytological diagnosis of HL can be challenging when classic RS cells are absent. Contributing factors for a false-negative diagnosis include obscuring reactive inflammatory cells, fibrosis of the involved lymph nodes, partial involvement of the lymph node, and misinterpretation. A thorough clinical examination with evaluation of FNAC smears from multiple areas, and ancillary tests help improve the diagnostic accuracy of cytological diagnosis.

Unraveling the complex role of neutrophils in lymphoma: From pathogenesis to therapeutic approaches (Review)

Lymphoma, a malignancy of the lymphatic system, which is critical for maintaining the body's immune defenses, has become a focal point in recent research due to its intricate interplay with neutrophils-white blood cells essential for combating infections and inflammation. Unlike prior perceptions associating neutrophils only with tumor support, contemporary studies underscore their intricate and multifaceted involvement in the immune response to lymphoma. Recognizing the nuanced participation of neutrophils in lymphoma is crucial for developing innovative treatments to improve patient outcomes.

A significant proportion of classic Hodgkin lymphoma recurrences represents clonally unrelated second primary lymphoma

Despite high cure rates in classic Hodgkin lymphoma (cHL), relapses are observed. Whether relapsed cHL represents second primary lymphoma or an underlying T-cell lymphoma (TCL) mimicking cHL is underinvestigated. To analyze the nature of cHL recurrences, in-depth clonality testing of immunoglobulin (Ig) and T-cell receptor (TCR) rearrangements was performed in paired cHL diagnoses and recurrences among 60 patients, supported by targeted mutation analysis of lymphoma-associated genes. Clonal Ig rearrangements were detected by next-generation sequencing (NGS) in 69 of 120 (58%) diagnoses and recurrence samples. The clonal relationship could be established in 34 cases, identifying clonally related relapsed cHL in 24 of 34 patients (71%). Clonally unrelated cHL was observed in 10 of 34 patients (29%) as determined by IG-NGS clonality assessment and confirmed by the identification of predominantly mutually exclusive gene mutations in the paired cHL samples. In recurrences of >2 years, ∼60% of patients with cHL for whom the clonal relationship could be established showed a second primary cHL. Clonal TCR gene rearrangements were identified in 14 of 125 samples (11%), and TCL-associated gene mutations were detected in 7 of 14 samples. Retrospective pathology review with integration of the molecular findings were consistent with an underlying TCL in 5 patients aged >50 years. This study shows that cHL recurrences, especially after 2 years, sometimes represent a new primary cHL or TCL mimicking cHL, as uncovered by NGS-based Ig/TCR clonality testing and gene mutation analysis. Given the significant therapeutic consequences, molecular testing of a presumed relapse in cHL is crucial for subsequent appropriate treatment strategies adapted to the specific lymphoma presentation.

The Tumor Microenvironment in Classic Hodgkin's Lymphoma in Responder and No-Responder Patients to First Line ABVD Therapy

Although classical Hodgkin lymphoma (CHL) is typically curable, 15-25% of individuals eventually experience a relapse and pass away from their disease. In CHL, the cellular microenvironment is constituted by few percent of H/RS (Hodgkin/Reed-Sternberg) tumor cells surrounded from a heterogeneous infiltration of inflammatory cells. The interplay of H/RS cells with other immune cells in the microenvironment may provide novel strategies for targeted immunotherapies. In this paper we analyzed the microenvironment content in CHL patients with responsive disease (RESP) and patients with relapsed/refractory disease to treatment (REL). Our results indicate the increase of CD68+ and CD163+ macrophages, the increase of PDL-1+ cells and of CD34+ microvessels in REL patients respective to RESP patients. In contrast we also found the decrease of CD3+ and of CD8+ lymphocytes in REL patients respective to RESP patients. Finally, in REL patients our results show the positive correlation between CD68+ macrophages and PDL-1+ cells as well as a negative correlation between CD163+ and CD3+.

Misdiagnosis analysis of 2291 cases of haematolymphoid neoplasms

Objective

To retrospectively analyze the reasons for misdiagnosis of haematolymphoid neoplasms and provide experience for improving the diagnostic level in China.

Methods

A retrospective analysis was performed on 2291 cases of haematolymphoid diseases evaluated by the Department of Pathology of our hospital from 1 July 2019 to 30 June 2021. All 2291 cases were reviewed by two hematopathologist experts and classified according to the 2017 revised WHO classification criteria, supplemented immunohistochemistry (IHC), molecular biology and genetic information as needed. The diagnostic discordance between primary and expert review was evaluated. The possible causes of the diagnostic discrepancies were analyzed for each step involved in the procedure of diagnosis.

Results

In total, 912 cases did not conform to the expert diagnoses among all the 2291 cases, with a total misdiagnosis rate of 39.8%. Among them, misdiagnosis between benign and malignant lesions accounted for 24.3% (222/912), misdiagnosis between haematolymphoid neoplasms and non-haematolymphoid neoplasms accounted for 3.3% (30/912), misdiagnosis among lineages accounted for 9.3% (85/912), misclassification in lymphoma subtypes accounted for 60.8% (554/912), and other misdiagnoses among benign lesions accounted for 2.3% (21/912) of cases, among which misclassification of lymphoma subtypes was the most common.

Conclusion

The accurate diagnosis of haematolymphoid neoplasms is challenging, involving various types of misdiagnosis and complicated causes, however, it is important for precise treatment. Through this analysis, we aimed to highlight the importance of accurate diagnosis, avoid diagnostic pitfalls and to improve the diagnostic level in our country.

Evolution in the definition and diagnosis of the Hodgkin lymphomas and related entities

Hodgkin lymphoma was the first of the lymphomas to be recognized as a specific disease entity. However, recent studies have highlighted the heterogeneity of the diseases associated with this eponym warranting clarification and refinement of diagnostic terminology. While classic Hodgkin lymphoma (CHL) remains an essentially unchanged diagnostic entity in the 2022 International Consensus Classification of Mature Lymphoid Neoplasms (2022 ICC), nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is now renamed nodular lymphocyte predominant B cell lymphoma (NLPBL) in recognition of the distinct pathologic, biologic, and clinical differences. Fan patterns A, B, and C (sharing the presence of evident follicular structures, and retention of a B cell rich background) will be combined in "typical" or grade 1, while the other "variant" patterns, D, E, and F, are considered grade 2. T-cell/histiocyte-rich large B cell lymphoma (THRBCL) is considered part of the "variant" NLPHL continuum.The entity previously known as "B cell lymphoma, unclassifiable (BCLU), with features intermediate between diffuse large B cell lymphoma (DLBCL) and CHL" has been renamed "mediastinal gray zone lymphoma" (MGZL) in recognition of the importance of the thymic niche in the biology of this tumor. The diagnostic criteria for MGZL have been refined and require both a high tumor cell density and a strongly preserved B cell program.This article will describe updates on CHL, NLPBL, and MGZL in the recently published 2022 ICC and provide some useful differential diagnostic clues in cases with atypical morphology or immunophenotype.

Diagnostic approach for classic Hodgkin lymphoma in small samples with an emphasis on PD-L1 expression and EBV harboring in tumor cells: a brief review from morphology to biology

Classic Hodgkin lymphoma (CHL) was first described in 1832 by Thomas Hodgkin, and is characterized by a small number of Hodgkin and Reed-Sternberg cells in a rich inflammatory background. However, even in this modern era, due to the histological and biological overlap with CHL and other B-cell malignancies, including mediastinal grey zone lymphoma and other lymphomas accompanied by "Hodgkinoid cells", their discrimination is challenging and sometimes impossible. The complexity and ambiguity of the boundaries of CHL and its related diseases make the definition of CHL unresolved. Our group has studied the significance of PD-L1 expression and infection of Epstein-Barr virus (EBV) in the diagnosis of CHL, emphasizing their pathological role, clinical significance, and high reproducibility even in daily clinical practice. In this review, we summarize the diagnostic strategy of CHL and its histological lookalikes based on neoplastic PD-L1 expression and infection of EBV, and attempt a reappraisal of the definition of CHL.

Novel Approaches in Molecular Characterization of Classical Hodgkin Lymphoma

Simple Summary

The unique tumor composition of classical Hodgkin lymphoma (cHL), with only a small fraction of malignant Hodgkin and Reed–Sternberg cells within the tumor tissue, has created many challenges to characterize the genetic alterations that drive this lymphoid malignancy. Major advances in sequencing technologies and detailed analysis of circulating tumor DNA in blood samples of patients have provided important contributions to enhance our understanding of the pathogenesis of cHL. In this review, we provide an overview of the recent advances in genotyping the clonal and mutational landscape of cHL. In addition, we discuss different next-generation sequencing applications to characterize tumor tissue and cell-free DNA, which are now available to improve the diagnosis of cHL, and to monitor therapeutic response or disease progression during treatment and follow up of cHL patients.

Abstract

Classical Hodgkin lymphoma (cHL) represents a B-cell lymphoproliferative disease characterized by clonal immunoglobulin gene rearrangements and recurrent genomic aberrations in the Hodgkin Reed–Sternberg cells in a reactive inflammatory background. Several methods are available for the molecular analysis of cHL on both tissue and cell-free DNA isolated from blood, which can provide detailed information regarding the clonal composition and genetic alterations that drive lymphoma pathogenesis. Clonality testing involving the detection of immunoglobulin and T cell receptor gene rearrangements, together with mutation analysis, represent valuable tools for cHL diagnostics, especially for patients with an atypical histological or clinical presentation reminiscent of a reactive lesion or another lymphoma subtype. In addition, clonality assessment may establish the clonal relationship of composite or subsequent lymphoma presentations within one patient. During the last few decades, more insight has been obtained on the molecular mechanisms that drive cHL development, including recurrently affected signaling pathways (e.g., NF-κB and JAK/STAT) and immune evasion. We provide an overview of the different approaches to characterize the molecular composition of cHL, and the implementation of these next-generation sequencing-based techniques in research and diagnostic settings.

Hodgkin Lymphoma: Biology and Differential Diagnostic Problem

Hodgkin lymphomas (HLs) are lymphoid neoplasms that are morphologically defined as being composed of dysplastic cells, namely, Hodgkin and Reed–Sternberg cells, in a reactive inflammatory background. The biological nature of HLs has long been unclear; however, our understanding of HL-related genetics and tumor microenvironment interactions is rapidly expanding. For example, cell surface overexpression of programmed cell death 1 ligand 1 (CD274/PD-L1) is now considered a defining feature of an HL subset, and targeting such immune checkpoint molecules is a promising therapeutic option. Still, HLs comprise multiple disease subtypes, and some HL features may overlap with its morphological mimics, posing challenging diagnostic and therapeutic problems. In this review, we summarize the recent advances in understanding the biology of HLs, and discuss approaches to differentiating HL and its mimics.

The Grey Zones of Classic Hodgkin Lymphoma

Simple Summary

Classic Hodgkin lymphoma (CHL) is a well-defined lymphoid neoplasm with a minority of characteristic neoplastic cells of B cell origin, namely Hodgkin and Reed–Sternberg cells immersed in a rich reactive inflammatory infiltrate in the background. Although CHL has always been set apart from non-Hodgkin lymphomas, cases with morphological and phenotypic features intermediate between CHL and other lymphomas have been described. Whereas some of these lymphomas only represent morphological mimics, others exhibit mutational and gene expression profiles which overlap with CHL, indicating that these cases, frequently termed grey zone lymphomas, reside on the biological boundary between CHL and large B-cell lymphomas. In the present review, we aim to describe the current knowledge of these rare lymphomas, address diagnostic issues and summarize today’s concepts on the classification of grey zone lymphomas and related tumors.

Abstract

Classic Hodgkin lymphoma (CHL) is a well-defined neoplasm characterized by the presence of a minority of pathognomonic Hodgkin and Reed–Sternberg (HRS) cells in a reactive inflammatory background. Although genotypically of B cell origin, HRS cells exhibit a downregulated B cell program and therefore are set apart from other B cell lymphomas in the current WHO classification. However, cases with morphological and phenotypic features overlapping with CHL have been recognized, and the category of B cell lymphoma—unclassifiable—with features intermediate between diffuse large B cell lymphoma (DLBCL) and CHL, also termed grey zone lymphoma, was first introduced into the WHO classification in 2008 as provisional entity. These cases, as well as others raising a differential diagnosis of CHL can present diagnostic problems, as well as therapeutic challenges. Whereas some of these lymphomas only represent biologically unrelated morphological mimics, others, especially mediastinal grey zone lymphoma, exhibit genetic and gene expression profiles which overlap with CHL, indicating a true biological relationship. In this review, we address areas of diagnostic difficulties between CHL and other lymphoma subtypes, discuss the biological basis of true grey zone lymphoma based on recent molecular studies and delineate current concepts for the classification of these rare tumors.

Necrotizing Follicular Lymphoma of the Inguinal Region with Sternbergoid Cells: Clinical–Pathological Features of a Challenging Entity

Follicular lymphoma (FL) is one of the most common B-cell malignancies worldwide. While the diagnosis of conventional cases is straightforward, rare clinical–pathological variants may be challenging due to their misleading morphology, aberrant phenotype and/or atypical presentation. To add to the spectrum of unusual FLs, we report on a rare disease pattern characterized by (i) inguinal presentation, (ii) massive necrosis, (iii) Hodgkin/Reed–Sternberg (HRS)-like cells, and (iv) adjacent areas of diffuse large B-cell lymphoma evolution. All cases occurred in elderly patients (median age at diagnosis: 69.5 years), disclosed a low stage at diagnosis (Ann Arbor stage IA-IIA), and had deceiving clinical features. Despite the alarming histology, excellent responses to conventional therapies were reported in all patients. In conclusion, necrotizing FL of the inguinal region is a rare neoplasm characterized by peculiar clinical and histological features. This lymphoma should always be considered in the differential diagnosis of massively necrotic inguinal lesions.

Clonality assessment and detection of clonal diversity in classic Hodgkin lymphoma by next-generation sequencing of immunoglobulin gene rearrangements

Clonality analysis in classic Hodgkin lymphoma (cHL) is of added value for correctly diagnosing patients with atypical presentation or histology reminiscent of T cell lymphoma, and for establishing the clonal relationship in patients with recurrent disease. However, such analysis has been hampered by the sparsity of malignant Hodgkin and Reed-Sternberg (HRS) cells in a background of reactive immune cells. Recently, the EuroClonality-NGS Working Group developed a novel next-generation sequencing (NGS)-based assay and bioinformatics platform (ARResT/Interrogate) to detect immunoglobulin (IG) gene rearrangements for clonality testing in B-cell lymphoproliferations. Here, we demonstrate the improved performance of IG-NGS compared to conventional BIOMED-2/EuroClonality analysis to detect clonal gene rearrangements in 16 well-characterized primary cHL cases within the IG heavy chain (IGH) and kappa light chain (IGK) loci. This was most obvious in formalin-fixed paraffin-embedded (FFPE) tissue specimens, where three times more clonal cases were detected with IG-NGS (9 cases) compared to BIOMED-2 (3 cases). In total, almost four times more clonal rearrangements were detected in FFPE with IG-NGS (N = 23) as compared to BIOMED-2/EuroClonality (N = 6) as judged on identical IGH and IGK targets. The same clonal rearrangements were also identified in paired fresh frozen cHL samples. To validate the neoplastic origin of the detected clonotypes, IG-NGS clonality analysis was performed on isolated HRS cells, demonstrating identical clonotypes as detected in cHL whole-tissue specimens. Interestingly, IG-NGS and HRS single-cell analysis after DEPArray™ digital sorting revealed rearrangement patterns and copy number variation profiles indicating clonal diversity and intratumoral heterogeneity in cHL. Our data demonstrate improved performance of NGS-based detection of IG gene rearrangements in cHL whole-tissue specimens, providing a sensitive molecular diagnostic assay for clonality assessment in Hodgkin lymphoma.

EBV-Driven Lymphoproliferative Disorders and Lymphomas of the Gastrointestinal Tract: A Spectrum of Entities with a Common Denominator (Part 3)

EBV is the first known oncogenic virus involved in the development of several tumors. The majority of the global population are infected with the virus early in life and the virus persists throughout life, in a latent stage, and usually within B lymphocytes. Despite the worldwide diffusion of EBV infection, EBV-associated diseases develop in only in a small subset of individuals often when conditions of immunosuppression disrupt the balance between the infection and host immune system. EBV-driven lymphoid proliferations are either of B-cell or T/NK-cell origin, and range from disorders with an indolent behavior to aggressive lymphomas. In this review, which is divided in three parts, we provide an update of EBV-associated lymphoid disorders developing in the gastrointestinal tract, often representing a challenging diagnostic and therapeutic issue. Our aim is to provide a practical diagnostic approach to clinicians and pathologists who face this complex spectrum of disorders in their daily practice. In this part of the review, the chronic active EBV infection of T-cell and NK-cell type, its systemic form; extranodal NK/T-cell lymphoma, nasal type and post-transplant lymphoproliferative disorders are discussed.

Cutaneous Localization of Classic Hodgkin Lymphoma Associated with Mycosis Fungoides: Report of a Rare Event and Review of the Literature

Mycosis fungoides and nodal classic Hodgkin lymphoma (cHL) have been reported to occur concurrently or sequentially in the same patient. A long-lasting mycosis fungoides more often precedes the onset of nodal cHL, although few cases of nodal cHL followed by mycosis fungoides have been observed. Skin involvement is a rare manifestation of cHL that may be observed in the setting of advanced disease. The decrease in skin involvement in cHL is mainly due to the improved therapeutic strategies. The concurrent presence of mycosis fungoides and cutaneous localization of classic Hodgkin lymphoma represents a very uncommon event, with only two cases reported so far. Herein, we describe the case of a 71-year-old man, with a history of recurrent nodal cHL, who developed MF and, subsequently, the cutaneous localization of cHL. The clinicopathological features of the two diseases are described focusing on the main differential diagnoses to be taken into consideration, and a review of the literature is performed.

EBV-Driven Lymphoproliferative Disorders and Lymphomas of the Gastrointestinal Tract: A Spectrum of Entities with a Common Denominator (Part 1)

EBV is the most common persistent virus in humans. The interaction of EBV with B lymphocytes, which are considered the virus reservoir, is at the base of the life-long latent infection. Under circumstances of immunosuppression, the balance between virus and host immune system is altered and hence, EBV-associated lymphoid proliferations may originate. These disorders encompass several entities, ranging from self-limited diseases with indolent behavior to aggressive lymphomas. The virus may infect not only B-cells, but even T- and NK-cells. The occurrence of different types of lymphoid disorders depends on both the type of infected cells and the state of host immunity. EBV-driven lymphoproliferative lesions can rarely occur in the gastrointestinal tract and may be missed even by expert pathologists due to both the uncommon site of presentation and the frequent overlapping morphology and immunophenotypic features shared by different entities. The aim of this review is to provide a comprehensive overview of the current knowledge of EBV-associated lymphoproliferative disorders, arising within the gastrointestinal tract. The review is divided in three parts. In this part, the available data on EBV biology, EBV-positive mucocutaneous ulcer, EBV-positive diffuse large B-cell lymphoma, not otherwise specified and classic Hodgkin lymphoma are discussed.