Lymphocyte-Rich Classical Hodgkin's Lymphoma: Clinical Presentation and Treatment Outcome in 100 Patients Treated Within German Hodgkin's Study Group Trials

Angioimmunoblastic T-Cell Lymphoma after Treatment of Classic Hodgkin Lymphoma: A Case Report

We report a case of a 24-year-old man who developed angioimmunoblastic T-cell lymphoma (AITL) after treatment for refractory lymphocyte-rich classic Hodgkin lymphoma (LR-CHL). This patient was treated with the BV+AVD (brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine) protocol for LR-CHL but progressed before completing chemotherapy. The pathological imaging showed the typical findings of LR-CHL at the first onset and first progression. Rescue chemotherapy and high-dose chemotherapy combined with autologous hematopoietic stem cell transplantation (AHSCT) were performed for refractory LR-CHL, and complete remission was achieved. However, the recurrence was suspected 6 months after AHSCT. The pathological findings of the lymph node biopsy at this time were different from those of the previous two lymph node biopsies, demonstrating findings of AITL. The finding of the immunohistochemical staining and polymerase chain reaction results supported the diagnosis. Although it has been reported that the risk for the development of non-Hodgkin lymphoma after treatment for Hodgkin lymphoma is increased, most are B-cell lymphomas, and few cases of AITL have been reported. AITL is a type of peripheral T-cell lymphoma that generally occurs in middle-aged and elderly people and that rarely occurs in young people. Here, we were able to make an accurate diagnosis by performing re-examination even when recurrence of LR-CHL was suspected. As there are no detailed case reports of AITL developing into secondary non-Hodgkin lymphoma, here we report on an identified case.

POLRMT over-expression is linked to WNT/beta-catenin signaling, immune infiltration, and unfavorable outcomes in lung adenocarcinoma patients

BACKGROUND

Mitochondrial RNA polymerase (POLRMT) is essential for the expression of mitochondrial genes. In recent studies, POLRMT expression promoted non-small cell cancer cell proliferation in cell lines and xenografts. The present study investigated the impact of POLRMT expression and function on lung adenocarcinoma (LUAD) patients.

METHOD

Multi-omics data (genomics, transcriptomics, and proteomics) from publicly available databases were used to assess the role of POLRMT expression and function in LUAD. These findings were further verified using cancer tissues from clinical samples.

RESULTS

POLRMT was over-expressed in LUADs, with mutation frequencies ranging from 1.30% to 5.71%. Over-expression of POLRMT was associated with an abnormal clinicopathological condition resulting in a decreased lifespan. Furthermore, gene sets enrich analysis revealed that POLRMT expression was linked to WNT/beta-catenin signaling; the expression of downstream target genes was positively correlated with POLRMT expression. Also, POLRMT expression was positively correlated with immunosuppressive genes, thereby affecting immune infiltration.

CONCLUSION

POLRMT is over-expressed in LUAD, thereby impacting patient survival. It is also involved in WNT/beta-catenin signaling and may affect tumor infiltration.

Classical Hodgkin Lymphoma: From Past to Future-A Comprehensive Review of Pathophysiology and Therapeutic Advances

Hodgkin lymphoma, a hematological malignancy of lymphoid origin that typically arises from germinal-center B cells, has an excellent overall prognosis. However, the treatment of patients who relapse or develop resistant disease still poses a substantial clinical and research challenge, even though current risk-adapted and response-based treatment techniques produce overall survival rates of over 95%. The appearance of late malignancies after the successful cure of primary or relapsed disease continues to be a major concern, mostly because of high survival rates. Particularly in pediatric HL patients, the chance of developing secondary leukemia is manifold compared to that in the general pediatric population, and the prognosis for patients with secondary leukemia is much worse than that for patients with other hematological malignancies. Therefore, it is crucial to develop clinically useful biomarkers to stratify patients according to their risk of late malignancies and determine which require intense treatment regimens to maintain the ideal balance between maximizing survival rates and avoiding late consequences. In this article, we review HL's epidemiology, risk factors, staging, molecular and genetic biomarkers, and treatments for children and adults, as well as treatment-related adverse events and the late development of secondary malignancies in patients with the disease.

Role of Artificial Intelligence in PET/CT Imaging for Management of Lymphoma

Our review shows that AI-based analysis of lymphoma whole-body FDG-PET/CT can inform all phases of clinical management including staging, prognostication, treatment planning, and treatment response evaluation. We highlight advancements in the role of neural networks for performing automated image segmentation to calculate PET-based imaging biomarkers such as the total metabolic tumor volume (TMTV). AI-based image segmentation methods are at levels where they can be semi-automatically implemented with minimal human inputs and nearing the level of a second-opinion radiologist. Advances in automated segmentation methods are particularly apparent in the discrimination of lymphomatous vs non-lymphomatous FDG-avid regions, which carries through to automated staging. Automated TMTV calculators, in addition to automated calculation of measures such as Dmax are informing robust models of progression-free survival which can then feed into improved treatment planning.

Primary Bone Marrow HIV-Associated Hodgkin Lymphoma Complicated by Hemophagocytic Lymphohistiocytosis

The presentation of human immunodeficiency virus (HIV)-associated Hodgkin lymphoma can differ from that of the general population. More specifically, primary bone marrow Hodgkin lymphoma is an uncommon presentation that is more often reported in patients with HIV. Given the many overlapping symptoms of Hodgkin lymphoma and HIV as well as HIV-associated infections, diagnosis can be difficult and delayed. We describe a case of primary bone marrow HIV-associated Hodgkin lymphoma complicated by hemophagocytic lymphohistiocytosis (HLH) where the initial work-up was inconclusive. Our case demonstrates the importance of early consideration of HLH as well as the need for an early bone marrow biopsy in a cytopenic patient with a fever of unknown origin.

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.

Gray zone lymphoma effectively treated with cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab chemotherapy: A case report

BACKGROUND

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma (BCLu-DLBCL/cHL), also referred to as gray zone lymphoma (GZL), is known to share features with cHL and DLBCL. However, GZL is often difficult to diagnose. There is no consensus regarding the optimal therapeutic regimen. Most reported cases of GZL have been in Caucasian and Hispanic individuals, and its incidence is lower in African-American and Asian populations, including the Japanese population.

CASE SUMMARY

A 69-year-old female presented at our hospital with a growing mass on the right side of her neck. An elastic, soft mass measuring 9 cm × 6 cm was palpable in the right cervical region. Laboratory analyses showed pancytopenia, increased serum lactate dehydrogenase levels, and markedly increased levels of soluble interleukin-2 receptor. Enhanced computed tomography (CT) and fluorodeoxyglucose positron emission tomography (PET)/CT revealed multiple lesions throughout her body. She was diagnosed with GZL based on the characteristic pathological findings, the immunophenotype [CD20+, PAX5+, OCT2+/BOB1 (focal+), CD30+, CD15-], and the strong positive expression of neoplastic programmed cell death protein ligand 1 (PD-L1) in her lymphoma cells. The lymphoma was stage IV according to the Lugano classification and high-risk according to the International Prognostic Index for aggressive non-Hodgkin lymphoma. The patient received cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab (R-CHOP) chemotherapy because the tumor cells were CD20+. She has remained in complete remission for 3 years.

CONCLUSION

GZL was diagnosed based on histopathology and immunophenotyping with ancillary PD-L1 positivity. R-CHOP chemotherapy was an effective treatment.

An Update on the Pathology and Molecular Features of Hodgkin Lymphoma

Simple Summary

Hodgkin lymphomas (HLs) include two main types, classic HL (CHL) and nodular lymphocyte predominant HL (NLPHL). Recent molecular findings in HLs have contributed to dramatic changes in the treatment and identification of tumor characteristics. For example, PD-1/PD-L1 blockade and brentuximab vedotin, an anti-CD30 antibody bearing a cytotoxic compound, are now widely used in patients with CHL. Biological continuity between NLPHL and T-cell/histiocyte-rich large B-cell lymphoma has been highlighted. An era of novel therapeutics for HL has begun. The aim of this paper is to review the morphologic, immunophenotypic, and molecular features of CHL and NLPHL, which must be understood for the development of novel therapeutics.

Abstract

Hodgkin lymphomas (HLs) are lymphoid neoplasms derived from B cells and consist histologically of large neoplastic cells known as Hodgkin and Reed–Sternberg cells and abundant reactive bystander cells. HLs include two main types, classic HL (CHL) and nodular lymphocyte predominant HL (NLPHL). Recent molecular analyses have revealed that an immune evasion mechanism, particularly the PD-1/PD-L1 pathway, plays a key role in the development of CHL. Other highlighted key pathways in CHL are NF-κB and JAK/STAT. These advances have dramatically changed the treatment for CHL, particularly relapsed/refractory CHL. For example, PD-1 inhibitors are now widely used in relapsed/refractory CHL. Compared with CHL, NLPHL is more characterized by preserved B cell features. Overlapping morphological and molecular features between NLPHL and T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) have been reported, and biological continuity between these two entities has been highlighted. Some THRLBCLs are considered to represent progression from NLPHLs. With considerable new understanding becoming available from molecular studies in HLs, therapies and classification of HLs are continually evolving. This paper offers a summary of and update on the pathological and molecular features of HLs for a better understanding of the diseases.

Nodular Lymphocyte-Predominant Hodgkin Lymphoma: Review of Current Literature and Case Discussion

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare subset of Hodgkin lymphoma (HL). It has a distinct clinical and pathological presentation. Unlike classic HL, where the predominant malignant cells are Reed Sternberg cells, the malignant cells in NLPHL are known as lymphocyte predominant (LP) cells, with their own unique immunohistochemistry antigen expression and staining pattern. Based on risk stratification and staging of the disease, treatment can range from active surveillance in asymptomatic patients with no organ compromise or bulky disease, to aggressive chemotherapeutic agents in advanced disease. Guidelines on which of these chemotherapy regimens would offer the most benefit to our patients are limited due to lack of randomized-controlled studies. Majority of the current prospective data on treatment were inclusive of both HL and NLPHL. Thus, the regimens employed in treatment of NLPHL are similar to the ones used in HL, though NLPHL is often viewed as its own distinct entity. This article aims to review the current literature and future advances on treatment of this rare disease.

Primary Intramuscular Classic Hodgkin Lymphoma: A Rare Case Report

Hodgkin lymphoma (HL) is a hematologic malignancy that typically presents with lymphadenopathy. We herein report a patient with HL who presented with an intramuscular mass that required differentiation from an inflammatory lesion. A 65-year-old Japanese woman was referred to our hospital with a chief complaint of chronic and expanding tumor in her left thigh. By surgical resection, she was diagnosed with primary intramuscular, Epstein-Barr virus-positive, mixed-cellularity classic HL. She received combined modality therapy, resulting in a complete response. Primary intramuscular classic HL is extremely rare. It should be listed as a differential diagnosis of intramuscular tumors.

Single-cell profiling reveals the importance of CXCL13/CXCR5 axis biology in lymphocyte-rich classic Hodgkin lymphoma

Lymphocyte-rich classic Hodgkin lymphoma (LR-CHL) is a rare subtype of Hodgkin lymphoma. Recent technical advances have allowed for the characterization of specific cross-talk mechanisms between malignant Hodgkin Reed-Sternberg (HRS) cells and different normal immune cells in the tumor microenvironment (TME) of CHL. However, the TME of LR-CHL has not yet been characterized at single-cell resolution. Here, using single-cell RNA sequencing (scRNA-seq), we examined the immune cell profile of 8 cell suspension samples of LR-CHL in comparison to 20 samples of the mixed cellularity (MC, 9 cases) and nodular sclerosis (NS, 11 cases) subtypes of CHL, as well as 5 reactive lymph node controls. We also performed multicolor immunofluorescence (MC-IF) on tissue microarrays from the same patients and an independent validation cohort of 31 pretreatment LR-CHL samples. ScRNA-seq analysis identified a unique CD4⁺ helper T cell subset in LR-CHL characterized by high expression of Chemokine C-X-C motif ligand 13 (CXCL13) and PD-1. PD-1⁺CXCL13⁺ T cells were significantly enriched in LR-CHL compared to other CHL subtypes, and spatial analyses revealed that in 46% of the LR-CHL cases these cells formed rosettes surrounding HRS cells. MC-IF analysis revealed CXCR5⁺ normal B cells in close proximity to CXCL13⁺ T cells at significantly higher levels in LR-CHL. Moreover, the abundance of PD-1⁺CXCL13⁺ T cells in the TME was significantly associated with shorter progression-free survival in LR-CHL (P = 0.032). Taken together, our findings strongly suggest the pathogenic importance of the CXCL13/CXCR5 axis and PD-1⁺CXCL13⁺ T cells as a treatment target in LR-CHL.

Retrospective analyses of other iatrogenic immunodeficiency-associated lymphoproliferative disorders in patients with rheumatic diseases

Other iatrogenic immunodeficiency‐associated lymphoproliferative disorders (OIIA‐LPDs) occur in patients receiving immunosuppressive drugs for autoimmune diseases; however, their clinicopathological and genetic features remain unknown. In the present study, we analysed 67 patients with OIIA‐LPDs, including 36 with diffuse large B‐cell lymphoma (DLBCL)‐type and 19 with Hodgkin lymphoma (HL)‐type. After discontinuation of immunosuppressive drugs, regression without relapse was achieved in 22 of 58 patients. Spontaneous regression was associated with Epstein–Barr virus positivity in DLBCL‐type (P = 0·013). The 2‐year overall survival and progression‐free survival (PFS) at a median follow‐up of 32·4 months were 92·7% and 72·1% respectively. Furthermore, a significant difference in the 2‐year PFS was seen between patients with DLBCL‐type and HL‐type OIIA‐LPDs (81·0% vs. 40·9% respectively, P = 0·021). In targeted sequencing of 47 genes in tumour‐derived DNA from 20 DLBCL‐type OIIA‐LPD samples, histone‐lysine N‐methyltransferase 2D (KMT2D; eight, 40%) and tumour necrosis factor receptor superfamily member 14 (TNFRSF14; six, 30%) were the most frequently mutated genes. TNF alpha‐induced protein 3 (TNFAIP3) mutations were present in four patients (20%) with DLBCL‐type OIIA‐LPD. Cases with DLBCL‐type OIIA‐LPD harbouring TNFAIP3 mutations had shorter PFS and required early initiation of first chemotherapy. There were no significant factors for spontaneous regression or response rates according to the presence of mutations. Overall, OIIA‐LPDs, especially DLBCL‐types, showed favourable prognoses.

Hodgkin lymphoma

Hodgkin lymphoma (HL) is a B cell lymphoma characterized by few malignant cells and numerous immune effector cells in the tumour microenvironment. The incidence of HL is highest in adolescents and young adults, although HL can affect elderly individuals. Diagnosis is based on histological and immunohistochemical analyses of tissue from a lymph node biopsy; the tissue morphology and antigen expression profile enable classification into one of the four types of classic HL (nodular sclerosis, mixed cellularity, lymphocyte-depleted or lymphocyte-rich HL), which account for the majority of cases, or nodular lymphocyte-predominant HL. Although uncommon, HL remains a crucial test case for progress in cancer treatment. HL was among the first systemic neoplasms shown to be curable with radiation therapy and multiagent chemotherapy. The goal of multimodality therapy is to minimize lifelong residual treatment-associated toxicity while maintaining high levels of effectiveness. Recurrent or refractory disease can be effectively treated or cured with high-dose chemotherapy followed by autologous haematopoietic stem cell transplantation, and prospective trials have demonstrated the potency of immunotherapeutic approaches with antibody-drug conjugates and immune checkpoint inhibitors. This Primer explores the wealth of information that has been assembled to understand HL; these updated observations verify that HL investigation and treatment remain at the leading edge of oncological research.

Clinicopathological significance of CD79a expression in classic Hodgkin lymphoma

Classic Hodgkin lymphoma (CHL) is a lymphoid neoplasia characterized by the presence of large tumor cells, referred to as Hodgkin and Reed-Sternberg (HRS) cells, originating from B-cells in an inflammatory background. As the clinical significance of B-cell markers has yet to be fully elucidated, this study aimed to clarify the clinicopathological significance of CD79a in 55 patients with CHL. They were immunohistochemically divided into two groups, comprising of 20 CD79a-positive and 35 CD79a-negative patients. There was no significant correlation between CD79a and CD20 expression (r_^s = 0.125, P = 0.362). CD79a-positive patients were significantly older at onset (P = 0.011). There was no significant correlation between CD79a-positivity and clinical stage (P = 0.203), mediastinal involvement (P = 0.399), extranodal involvement (P = 0.749), or laboratory findings, including serum levels of lactate dehydrogenase (P = 1) and soluble interleukin-2 receptor (P = 0.251). There were significant differences in overall survival (OS) (P = 0.005) and progression-free survival (PFS) (P = 0.007) between CD79a-positive and CD79a-negative patients (5-year OS: 64.6% and 90.5%; 5-year PFS: 44.0% and 76.6%, respectively). Five patients in whom the majority (> 80%) of HRS cells expressed CD79a consisted of 4 males and 1 female aged between 52 and 81 years; 4 of them were in a limited clinical stage. We concluded that CD79a-positive CHL may have unique clinicopathological features.

Impact of ABVD chemotherapy on ovarian reserve after fertility preservation in reproductive-aged women with Hodgkin lymphoma

RESEARCH QUESTION

How is ovarian reserve affected by chemotherapy in patients with Hodgkin lymphoma (HL) who undergo fertility preservation (FP)?

METHODS

A retrospective study was conducted by reviewing medical records of 105 HL patients referred to the FP unit before starting adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy. Ovarian reserve was evaluated before chemotherapy and at the last follow-up using anti-Müllerian hormone (AMH) and antral follicle count (AFC) measurements. The decrease in AMH was compared with that expected from normograms. AMH was compared between patients who underwent cryopreservation of ovarian tissue and those who underwent cryopreservation of mature oocytes.

RESULTS

After ABVD, 15% of patients required hematopoietic stem cell transplantation. At a median follow-up of 33 months, the median decrease in AMH was 0.88 ng/mL, which was significantly greater than that of the general population of this age group (p < 0.001). Of the 82 women who only had ABVD, 38 underwent FP by cryopreservation of mature oocytes and 44 underwent cryopreservation of the ovarian cortex. There was no significant difference in AMH or AFC at the last follow-up between FP techniques.

CONCLUSION

Although ABVD is considered to be of low gonadotoxic risk, the decrease in AMH was greater than expected for patients' age, and 15% of patients needed more aggressive therapy during follow-up. Type of FP was not associated with decline in ovarian reserve. Reproductive-aged women with HL should have the opportunity for FP counseling before starting treatment.

Update on the classification of T-cell lymphomas, Hodgkin lymphomas, and histiocytic/dendritic cell neoplasms

Introduction: The classification of lymphomas is based on the postulated normal counterparts of lymphoid neoplasms and currently constitutes over 100 definite or provisional entities. As this number of entities implies, lymphomas show marked pathological, genetic, and clinical heterogeneity. Recent molecular findings have significantly advanced our understanding of lymphomas. Areas covered: The World Health Organization (WHO) classification of lymphoid neoplasms was updated in 2017. The present review summarizes the new findings that have been gained in the areas of mature T-cell neoplasms, Hodgkin lymphomas, and histiocytic/dendritic cell neoplasms since the publication of the 2017 WHO classification. Expert opinion: Although formal revisions to the WHO classification are published only periodically, our understanding of the pathologic, genetic, and clinical features of lymphoid neoplasms is constantly evolving, particularly in the age of -omics technologies and targeted therapeutics. Even in the relatively short time since the publication of the 2017 WHO classification, many significant findings have been identified in the entities covered in this review.

HIV positivity may not have a negative impact on survival in Epstein-Barr virus-positive Hodgkin lymphoma: A Japanese nationwide retrospective survey

There has been no comparative clinical study focused on differences in the clinical features of Epstein-Barr virus (EBV)⁺ Hodgkin lymphoma (HL) between HIV-positive and -negative cases. In a nationwide survey from 511 institutions in Japan, the present study investigated 16 EBV+ HIV^positive HL patients. To further clarify their characteristics in comparison with EBV+ HIV^negative HL (n=34) in the combination antiretroviral therapy era in Japan, the present study was performed. Results indicated that EBV⁺ HIV^positive HL frequently occurred in a younger population compared with EBV⁺ HIV^negative HL (P=0.0295), and that the EBV⁺ HIV^positive HL group was not associated with the nodular sclerosis subtype in the population who were below the age of 40. Notably, the EBV⁺ HIV^positive HL group had a significantly higher frequency of extra-nodal involvement (P=0.0214), including marrow invasion. In the advanced stage, 80% of those with EBV⁺ HIV^positive HL did not require dose-reduction and in the majority of cases, chemotherapy was completed. There were no significant differences in the complete remission rate (P=0.1961), overall survival (P=0.200) and progression-free survival (P=0.245) between EBV⁺ HIV^positive HL (median observational period, 23.5 months) and EBV⁺ HIV^negative HL (median observational period, 64.5 months), suggesting that HIV positivity may not have a negative impact on the clinical outcome of EBV⁺ HL. Notably, standard chemotherapy is effective and tolerable for EBV⁺ HL, regardless of HIV infection.

Bone marrow uptake of 18F-fluorodeoxyglucose in Hodgkin lymphoma without bone involvement: comparison between patients with and without B symptoms

Objective

To compare the degree of benign bone marrow uptake of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) between Hodgkin lymphoma patients with and without B symptoms.

Materials and Methods

We analyzed the medical charts of 74 Hodgkin lymphoma patients who underwent ¹⁸F-FDG positron emission tomography/computed tomography (PET/CT) prior to the initiation of therapy between October 2010 and September 2013. In all of the patients, the bone marrow biopsy was negative and the ¹⁸F-FDG PET/CT images did not suggest bone marrow involvement. Of the 74 patients evaluated, 54 presented inflammatory (B) symptoms and 20 did not. Regions of interest (ROIs) were drawn on the sternum, the proximal thirds of the humeri, the proximal thirds of the femora, and both iliac wings (totaling seven ROIs per patient). To compare the patients with and without B symptoms, in terms of standardized uptake values (SUVs) for the seven ROIs, we used the Mann-Whitney U test.

Results

For six of the ROIs, the SUVs were higher in the patients with B symptoms than in those without, and the difference was statistically significant (p < 0.05). There was also a tendency toward a statistically significant difference between the two groups in terms of the SUV for the right iliac wing ROI (p = 0.06).

Conclusion

In our sample, the presence of B symptoms was associated with increased ¹⁸F-FDG uptake in bone marrow.

Hodgkin lymphoma: A review and update on recent progress

Hodgkin lymphoma (HL) is a unique hematopoietic neoplasm characterized by cancerous Reed-Sternberg cells in an inflammatory background. Patients are commonly diagnosed with HL in their 20s and 30s, and they present with supradiaphragmatic lymphadenopathy, often with systemic B symptoms. Even in advanced-stage disease, HL is highly curable with combination chemotherapy, radiation, or combined-modality treatment. Although the same doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapeutic regimen has been the mainstay of therapy over the last 30 years, risk-adapted approaches have helped de-escalate therapy in low-risk patients while intensifying treatment for higher risk patients. Even patients who are not cured with initial therapy can often be salvaged with alternate chemotherapy combinations, the novel antibody-drug conjugate brentuximab, or high-dose autologous or allogeneic hematopoietic stem cell transplantation. The programmed death-1 inhibitors nivolumab and pembrolizumab have both demonstrated high response rates and durable remissions in patients with relapsed/refractory HL. Alternate donor sources and reduced-intensity conditioning have made allogeneic hematopoietic stem cell transplantation a viable option for more patients. Future research will look to integrate novel strategies into earlier lines of therapy to improve the HL cure rate and minimize long-term treatment toxicities. CA Cancer J Clin 2018;68:116-132. © 2017 American Cancer Society.

Nodular lymphocyte predominant Hodgkin's lymphoma in daily practice: A multicenter experience

Nodular lymphocyte predominant Hodgkin's lymphoma (NLPHL) is a rare subtype of Hodgkin's lymphoma. In this study, we aimed to investigate the clinical features and therapeutic outcomes of patients with NLPHL who were diagnosed at different institutes in Turkey. We retrospectively reviewed the records of the patients diagnosed with NLPHL. Adult patients who were diagnosed after 2005 with histological confirmation were selected for the study. Forty-three patients were included in the study. Median age of patients was 37.5 years (18-70) at the time of diagnosis. About 60.5% patients were diagnosed as stage I and II NLPHL, and remaining 39.5% had stage III and IV disease. Median follow-up was 46 months. During follow-up, none of the patients died. Seven patients relapsed or progressed after initial therapy at a median of 12 months. Five of 7 relapsed/refractory patients (71.4%) were salvaged with chemotherapy only (DHAP, ICE), and the remaining 2 (28.6%) were salvaged with chemoimmunotherapy. All of relapsed/refractory patients were able to achieve complete remission after salvage therapy. Lactate dehydrogenase levels were significantly higher in patients with progressive disease compared with nonprogressive disease. Our study showed an excellent outcome with all patients alive at last contact with a median follow up of 46 months despite a wide range of different therapeutic approaches. All relapsed and refractory patients were successfully salvaged despite a low frequency of patients received immunotherapy in conjunction with chemotherapy. Our results suggest that immunotherapy may be reserved for further relapses.

The Pathobiology and Treatment of Hodgkin Lymphoma. Where do We go from Gianni Bonadonna's Lesson?

This article reviews the evolution of the diagnosis and treatment of Hodgkin lymphoma (HL) since its discovery in 1832. The morphological, phenotypic and molecular characteristics of both nodular lymphocyte-predominant HL and classical HL are revised in the light of recent molecular information and possible impact on the identification of risk groups as well as the use of targeted therapies. The seminal contribution of Gianni Bonadonna to developing new treatment strategies for both advanced and early-stage HL is highlighted.

Lymphoma classification update: T-cell lymphomas, Hodgkin lymphomas, and histiocytic/dendritic cell neoplasms

INTRODUCTION

Lymphomas are classified based on the normal counterpart, or cell of origin, from which they arise. Because lymphocytes have physiologic immune functions that vary both by lineage and by stage of differentiation, the classification of lymphomas arising from these normal lymphoid populations is complex. Recent genomic data have contributed additional depth to this complexity. Areas covered: Lymphoma classification follows the World Health Organization (WHO) system, which reflects international consensus and is based on pathological, genetic, and clinical factors. The present review focuses on the classification of T-cell lymphomas, Hodgkin lymphomas, and histiocytic and dendritic cell neoplasms, summarizing changes reflected in the 2016 revision to the WHO classification. These changes are critical to hematologists and other clinicians who care for patients with these disorders. Expert commentary: Lymphoma classification is a continually evolving field that needs to be responsive to new clinical, pathological, and molecular understanding of lymphoid neoplasia. Among the entities covered in this review, the 2016 revisions in the WHO classification particularly impact T-cell lymphomas, including a new umbrella category of T-follicular helper cell-derived lymphomas and evolving recognition of indolent T-cell lymphomas and lymphoproliferative disorders.

Treating Adults with Hodgkin Lymphoma in the Developing World: a Hospital-Based Cohort Study from Armenia

BACKGROUND

With advances in diagnostics and treatment approaches, patients with Hodgkin's lymphoma (HL) in developed countries can nowadays expect to have excellent outcomes. However, information about the characteristics and outcomes in the developing world is very scarce, and this is important given the fact that there are several reports about differences of disease characteristics depending on geographic location and the development level of the country.

MATERIALS AND METHODS

In this retrospective study we assessed the features of 36 adult (≥18 years old) patients with HL and their diagnosis and treatment and outcomes in the Clinic of Chemotherapy of Muratsan University Hospital of Yerevan State Medical University, Armenia, between 2008- 2014.

RESULTS

All patients had classic HL and among them 19 (53%) had nodular sclerosis subtype, 8 (22%) mixed cellularity and 9 (25%) lymphocyte-rich. 16 (44.5%) patients were at stage II, 13 (36%) stage III and 7 (19.5%) stage IV. Median follow-up time was 24.5 months (range 1-71 months) and during the whole follow- up period only two relapses (early) were documented and there were no deaths. Twenty-three (64%) patients received a BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone) regimen, and 13 (36%) ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine) regimen. A total of 25 (69.5%) patients received radiation in addition to chemotherapy.

CONCLUSIONS

Although the number of patients involved in the study is small and the median follow-up time was just two years, this retrospective study shows that treatment of HL can be successfully organized in a resource-limited setting.

A 20-year population-based study on the epidemiology, clinical features, treatment, and outcome of nodular lymphocyte predominant Hodgkin lymphoma

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is a subtype of Hodgkin lymphoma characterized by a unique clinical and histological presentation. Because of the rare nature of this disease, few large-scale studies are available. We conducted a cohort study in which patients were identified in the Netherlands Cancer Registry in the Southeast of the Netherlands between 1990 and 2010. Of these patients, we collected all clinical characteristics and re-reviewed pathologic material to confirm NLPHL diagnosis. Seventy-three histologically confirmed cases of NLPHL were analyzed with a median follow-up of 65 months (range 4–257 months). Median age at diagnosis was 43 years (range 1–87); 84.9 % of the patients were male; B symptoms were present in 5.5 %; and stage I/II disease was most common (75.4 %). Patients were primarily treated with radiotherapy (50.7 %), chemotherapy (26 %), combined modality (radiotherapy and chemotherapy) (11 %), or surgical excision with careful watch-and-wait (12.3 %). Relapses occurred in seven patients (9.6 %) after a median of 26 months (21–74 months). Six patients (8.2 %) developed histologic transformation to large cell lymphoma. Five patients (6.8 %) died during follow-up due to progression of NLPHL (n = 1), histologic transformation (n = 2) and intercurrent deaths (n = 2). The estimated 10-year overall survival was 94.0 % and the 10-year progression-free survival 75.8 %. Our study confirms the distinct characteristics of NLPHL with a relatively good long-term prognosis. It may be possible to reduce treatment intensity in early stage NLPHL without affecting long-term outcome.

Advanced Lymphocyte-rich Classical Hodgkin Lymphoma Complicated with Fatal Hemophagocytic Syndrome

Lymphocyte-rich classical Hodgkin lymphoma (LRCHL) is a rare subtype of Hodgkin lymphoma with a favorable prognosis, and an aggressive clinical course of LRCHL is uncommon. A 55-year-old man suffering from swelling in the left neck was diagnosed with LRCHL with extranodal lesions in the lung and bone marrow. Initially, he received standard ABVD chemotherapy; however, disease progression, accompanied by hemophagocytic syndrome (HPS), occurred during the second course of ABVD. He received two subsequent courses of intensive chemotherapy containing high-dose steroids, cyclophosphamide, and etoposide. Nevertheless, this therapy was only temporarily effective, and he died of due to an aggressive disease progression accompanied by uncontrollable HPS and severe coagulopathy.

Classical Hodgkin lymphoma, lymphocyte depleted type: clinicopathological analysis and prognostic comparison with other types of classical Hodgkin lymphoma

The lymphocyte-depleted type (LD) is a morphological subtype of classical Hodgkin lymphoma (CHL), but its rarity and heterogeneous morphological character makes a definite clinicopathological identification difficult. To characterize this disease, LD cases were compared with other types of CHL. From 1982 to 2006, we collected 310 CHL cases. Among them, 29 cases were diagnosed as LD. We could additionally analyze clinical data of 157 CHL cases (including 28 LD cases) and the immunophenotype of 150 CHL cases (including 28 LD cases). We compared clinicopathological data between LD cases and other types of CHL cases and determined prognostic factors by univariate and multivariate analysis. LD showed a more progressive disease stage (stage 3/4, 64%) than other types of CHL (stage 3/4, 30%; P<0.001), more frequent B symptoms (89% vs. 40%; P<0.001) and extranodal invasion (50% vs. 11%; P<0.001), older age (median: 66 vs. 33; P<0.001), higher serum soluble interleukin 2 receptor levels (median: 8240U/ml vs. 1705U/ml; P<0.001), and much poorer prognosis regardless of the international prognostic score (IPS) (five-year overall survival: 29% vs. 86%; P<0.001). The morphological subtype of LD represented an independent prognostic factor as did age and IPS by multivariate analysis. Immunohistochemistry showed that the characteristics of Hodgkin and Reed-Sternberg (HRS) cells of LD are basically not different from those of other types of CHL in terms of CD30, CD15, and chemokine receptors, except for high-level EB-virus infection (72% vs. 41%; P=0.002). LD should be distinguished from other types of classical Hodgkin lymphoma because of its definitive clinicopathological characters.

Shades of gray between large B-cell lymphomas and Hodgkin lymphomas: differential diagnosis and biological implications

Hodgkin lymphomas (HLs) are neoplasms of large B cells. Two types are recognized: nodular lymphocyte predominant HL (NLPHL) and classical HL (CHL). In both types, there may be morphological and possibly biological overlap with large B-cell lymphomas (LBCLs) of non-HL types. These include nodular sclerosis CHL and primary mediastinal large B-cell lymphoma; CHL rich in lymphocytes and NLPHL; and NLPHL and T-cell/histiocyte-rich LBCL. This review covers the defining features of each of these diseases, the borderlines between them, and strategies for differential diagnosis.

Nodular lymphocyte predominant Hodgkin's lymphoma of the cervix: A case report of a rare entity

► The clinical presentation of a case of NLPHL involving the uterine cervix. ► The immunohistochemical characteristics, the management and outcome of the described case. ► A brief review of the literature on current treatment strategies of early-stage NLPHL.

Lymphocyte-Depleted Classical Hodgkin's Lymphoma: A Comprehensive Analysis From the German Hodgkin Study Group

Purpose

To investigate the clinical characteristics and treatment outcome of patients with lymphocyte-depleted classical Hodgkin's lymphoma (LDCHL) compared with other histologic subtypes of Hodgkin's lymphoma (HL).

Patients and Methods

From a total of 12,155 evaluable patients with biopsy-proven HL treated within the German Hodgkin Study Group trials HD4 to HD15, 10,019 patients underwent central expert pathology review. Eighty-four patients with LDCHL (< 1%) were identified and confirmed. The median follow-up time was 67 months.

Results

Patients with LDCHL, compared with patients with other histologic subtypes, presented more often with advanced disease (74% v 42%, respectively; P < .001) and “B” symptoms (76% v 41%, respectively; P < .001). Other risk factors were also more frequent in patients with LDCHL. Complete remission or unconfirmed complete remission was achieved in 82% of patients with LDCHL compared with 93% of patients with other HL subtypes (P < .001), and more patients with LDCHL had progressive disease. At 5 years, progression-free survival (PFS) and overall survival (OS) were significantly lower in patients with LDCHL compared with patients with other HL subtypes (PFS, 71% v 85%, respectively; P < .001; OS, 83% v 92%, respectively; P = .0018). However, when analyzing the subgroup of patients who underwent treatment with intensified or dose-dense bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone, patients with LDCHL (n = 39) had similar outcomes when compared with patients with other subtypes of HL (n = 3,564; P = .61).

Conclusion

LDCHL has a different pattern from other HL subtypes with more clinical risk factors at initial diagnosis and significantly poorer prognosis. Patients with LDCHL should be treated with modern dose-intense treatment strategies.

Subsequent development of diffuse large B-cell lymphomas and Hodgkin lymphoma associated with primary immune disorder in a 6-year-old female: a case report and review of the literature

Neoplastic lymphoid proliferation may arise from immune deficiency or disordered regulation of the immune system. Often the neoplasms are associated with viral agents, such as Epstein-Barr virus, human immunodeficiency virus, or human herpes virus 8. Lymphoproliferative diseases have been documented in a variety of primary immune disorders. The most commonly encountered neoplastic lesion is diffuse large B-cell lymphoma (DLBCL), although Hodgkin lymphoma (HL), Burkitt lymphoma, and peripheral T-cell lymphomas and/or leukemias have also been documented in rare instances. We report a case of a 6-year-old girl with unclassifiable primary immunodeficiency diagnosed with 2 different clones of DLBCLs and subsequently developed lymphocyte-depleted, classical HL. Both neoplasms were associated with Epstein-Barr virus. To the best of our knowledge, this is the first reported occurrence of primary immune disorder-associated lymphoproliferative disease with sequential development of DLBCLs and HL in a pediatric patient. Thorough surveillance is paramount for accurate assessment of the associated lymphoproliferative disease and in ascertaining likely transformation to, or de novo evolution of a different lymphoid neoplasm. This is also important in evaluating treatment response with appropriate therapeutic adjustments if clinically indicated.

Predicting treatment outcome in classical Hodgkin lymphoma: genomic advances

Classical Hodgkin lymphoma is considered a highly curable disease; however, 20% of patients cannot be cured with standard first-line chemotherapy and have a dismal outcome. Current clinical parameters do not allow accurate risk stratification, and personalized therapies are lacking. In fact, Hodgkin lymphoma (HL) is often over- or undertreated because of this lack of accurate risk stratification. In recent years, the early detection of chemoresistance by fluorodeoxyglucose positron emission tomography has become the most important prognostic tool in the management of HL. However, to date, no prognostic scores or molecular markers are available for the early identification of patients at very high risk of failure of induction therapy. In the last decade, many important advances have been made in understanding the biology of HL. In particular, the development of new molecular profiling technologies, such as SNP arrays, comparative genomic hybridization, and gene-expression profiling, have allowed the identification of new prognostic factors that may be useful for risk stratification and predicting response to chemotherapy. In this review, we focus on the prognostic tools and biomarkers that are available for newly diagnosed HL, and we highlight recent advances in the genomic characterization of classical HL and potential targets for therapy.

Hodgkin lymphoma at the paediatric oncology unit of gabriel touré teaching hospital, bamako, mali: 5-year experience

Introduction. The aim of this retrospective, unicentric study over 5 years is to describe the epidemiologic, pathologic, clinic and therapeutic aspects of children treated for Hodgkin lymphoma in our paediatric oncology unit. Patients and Methods. From January 2005 to December 2009, all children under 18 years of age, with Hodgkin lymphoma were included in this study. The treatment protocol was the GFAOP (Groupe Franco-Africain d'Oncologie Pédiatrique) Hodgkin lymphoma treatment protocol. Results. During the study period, 217 cancer cases were diagnosed in our centre. Of these cases, 7 were Hodgkin Lymphoma (LH) (0.04%). The mean age was 11.7 years. The sex-ratio was 6/1. 4% (5/7) of patients were stage IIB and 28.6% (2/7) stage IIIB of Ann-Arbor classification. There were 3 cases (42.8%) of sclero-nodular subtype, 2 cases (28.6%) of lymphocyte-rich classical HL subtype, 1 case (14.3%) of mixed cellularity and 1 case (14.3%) of lymphocyte depleted subtype. With a median followup of 37 months, 5 patients (71.4%) are alive, and 2 patients (28.6%) died. Conclusion. Broader multicentric studies are needed for more accurate data on this malignancy.

Classical Hodgkin's lymphoma arising in different host's conditions: pathobiology parameters, therapeutic options, and outcome

Epidemiologic and molecular findings suggest that classical Hodgkin's lymphoma (CHL) is not a single disease but consists of more than one entity and may occur in different clinical settings. This review analyzes similarities and disparities among CHL entities arising in different host's conditions with respect to pathobiology parameters, therapeutic options, and outcome. For the purpose of this analysis, CHL entities have been subdivided according to the immune status of the host. In nonimmunosuppressed hosts, according to the age, CHL include pediatric, adult, and elderly forms, whereas, in immunosuppressed hosts, according to the type of immunosuppression, CHL include human immunodeficiency virus (HIV)-associated, iatrogenic, and post-transplant types. CHL entities in different settings are similar in morphology of neoplastic cells, expression of activation markers, and aberrations/activation of NFKB, JAK/STAT, and P13K/AKT pathways, but differ in the association with Epstein-Barr virus (EBV) infection, persistent B-cell phenotype, and cellular background composition. Large B-cell lymphomas resembling CHL may also be observed in the same clinical settings. These lesions, however, do not fulfill the diagnostic criteria of CHL and clinically display a very aggressive behavior. In this article, current treatment options for the CHL entities, especially for elderly CHL and HIV-associated CHL, are specifically reviewed. ABVD remains the gold standard both in nonimmunosuppressed or immunosuppressed hosts even if there are several data suggesting a possible improvement in outcome using the aggressive BEACOPP regimen in advanced stages. Refractory CHL, a clinical condition that may occur throughout the entire spectrum of CHL, is discussed separately.

Febrile cholestatic disease as an initial presentation of nodular lymphocyte-predominant Hodgkin lymphoma

Febrile cholestatic liver disease is an extremely unusual presentation of Hodgkin lymphoma (HL). The liver biopsy of a 40-year-old man with febrile episodes and cholestatic laboratory pattern disclosed an uncommon subtype of HL, a nodular lymphocyte-predominant HL (NLPHL). Liver involvement in the early stage of the usually indolent NLPHL’s clinical course suggests an aggressiveness and unfavorable outcome. Emphasizing a liver biopsy early in the diagnostic algorithm enables accurate diagnosis and appropriate treatment. Although rare, HL should be considered in the differential diagnosis of cholestasis.

SARS spike protein induces phenotypic conversion of human B cells to macrophage-like cells

Massive aggregations of macrophages are frequently detected in afflicted lungs of patients with severe acute respiratory syndrome-associated coronavirus (SARS-CoV) infection. In vitro, ectopic expression of transcription factors, in particular CCAAT/enhancer-binding protein alpha (C/EBPα) and C/EBPβ, can convert B cells into functional macrophages. However, little is known about the specific ligands responsible for such phenotype conversion. Here, we investigated whether spike protein of SARS-CoV can act as a ligand to trigger the conversion of B cells to macrophages. We transduced SARS-CoV spike protein-displayed recombinant baculovirus (SSDRB), vAtEpGS688, into peripheral B cells and B lymphoma cells. Cell surface expression of CD19 or Mac-1 (CD11b) was determined by flow cytometry. SSDRB-mediated changes in gene expression profiles of B lymphoma cells were analyzed by microarray. In this report, we showed that spike protein of SARS virus could induce phenotypic conversion of human B cells, either from peripheral blood or B lymphoma cells, to macrophage-like cells that were steadily losing the B-cell marker CD19 and in turn expressing the macrophage-specific marker Mac-1. Furthermore, we found that SSDRB enhanced the expression of CD86, hypoxia-inducible factor-1α (HIF1α), suppressor of cytokine signaling (SOCS or STAT-induced STAT inhibitor)-3, C/EBPβ, insulin-like growth factor-binding protein 3 (IGFBP3), Krüpple-like factor (KLF)-5, and CD54, without marked influence on C/EBPα or PU.1 expression in transduced cells. Prolonged exposure to hypoxia could also induce macrophage-like conversion of B cells. These macrophage-like cells were defective in phagocytosis of red fluorescent beads. In conclusion, our results suggest that conversion of B cells to macrophage-like cells, similar to a pathophysiological response, could be mediated by a devastating viral ligand, in particular spike protein of SARS virus, or in combination with severe local hypoxia, which is a condition often observed in afflicted lungs of SARS patients.

Hodgkin lymphoma

Hodgkin disease was first described more than 175 years ago. Clinically and histomorphologically, the features of Hodgkin lymphoma are unusual for a lymphoma or for other malignancies. The incidence of Hodgkin lymphoma is estimated to be 7400 new cases per year in the United States, resulting in an age-adjusted yearly rate of 2.7 per 100,000 per year. There have been numerous classifications of non-Hodgkin lymphoma over the years, but the organizational schemes of Hodgkin lymphoma have been stable. This article reviews the diagnosis of the various types of Hodgkin lymphoma classification, diagnosis and differential.

Hodgkin lymphoma: an update on its biology with new insights into classification

In the past few years, there has been a greater understanding of the spectrum and biology of Hodgkin lymphoma (HL). In standard texts, HL is classified as 2 distinct entities, namely nodular lymphocyte-predominant HL and classical HL (CHL). However, recent evidence suggests that CHL is not a single disease. Although the mixed cellularity and lymphocyte-depleted subtypes might be part of a biologic continuum, the nodular sclerosis subtype has a distinct epidemiology, clinical presentation, and histology. Nodular sclerosis HL might also be related to primary mediastinal B-cell lymphoma and mediastinal gray-zone lymphomas. We present an update on the pathobiology of HL and discuss these biologic and clinical differences in this review.

Lymphocyte-rich classical Hodgkin's lymphoma: distinctive tumor and microenvironment markers

The existence, diagnostic features, and the biological and clinical relevance of lymphocyte-rich classical Hodgkin's lymphoma remain controversial. A comparative marker analysis of lymphocyte-rich classical Hodgkin's lymphoma, nodular lymphocyte-predominance Hodgkin's lymphoma, and of other subtypes of classical Hodgkin's lymphoma was carried out. Markers were selected focusing on B-cell lineage and transcription program (OCT.1, OCT.2, BOB.1, BCL6, PAX-5, GCET1, KLHL6, and BLIMP1), the NF-kappaB signaling pathway (REL-B, C-REL, TRAF-1, p-50, and MUM-1) and the T-cell microenvironment (CD3, CD57, PD-1, CXCL-13, and CD10, BCL-6, CD23). Lymphocyte-rich classical Hodgkin's lymphoma cases displayed features intermediate between those of classical Hodgkin's lymphoma and nodular lymphocyte-predominance Hodgkin's lymphoma. The expression of B-cell transcription factors such as OCT.1, OCT.2, BOB.1, and BCL6 was more frequent in lymphocyte-rich classical Hodgkin's lymphoma than in classical Hodgkin's lymphoma. A follicular T-cell microenvironment was also identified in 50% of lymphocyte-rich classical Hodgkin's lymphoma cases. NF-kB markers were expressed at frequencies comparable with those observed in classical Hodgkin's lymphoma. The neoplastic cell immunophenotype and microenvironment in lymphocyte-rich classical Hodgkin's lymphoma closely mimic that which are observed in the outer zone of the germinal center, where B-cell blasts with germinal-center markers co-express CD30 and the B-cell transcription program, surrounded by follicular T-cell rosettes. Lymphocyte-rich classical Hodgkin's lymphoma seems to be characterized by a stronger expression of the B-cell transcription program by the neoplastic cells and by a follicular T-cell background, occupying an intermediate position between classical Hodgkin's lymphoma and nodular lymphocyte-predominance Hodgkin's lymphoma.

Hodgkin lymphoma in the Swiss HIV Cohort Study

Hodgkin lymphoma (HL) risk is elevated among persons infected with HIV (PHIV) and has been suggested to have increased in the era of combined antiretroviral therapy (cART). Among 14,606 PHIV followed more than 20 years in the Swiss HIV Cohort Study (SHCS), determinants of HL were investigated using 2 different approaches, namely, a cohort and nested case-control study, estimating hazard ratios (HRs) and matched odds ratios, respectively. Forty-seven incident HL cases occurred during 84,611 person-years of SHCS follow-up. HL risk was significantly higher among men having sex with men (HR vs intravenous drug users = 2.44, 95% confidence interval [CI], 1.13-5.24) but did not vary by calendar period (HR for 2002-2007 vs 1995 or earlier = 0.65, 95% CI, 0.29-1.44) or cART use (HR vs nonusers = 1.02, 95% CI, 0.53-1.94). HL risk tended to increase with declining CD4(+) cell counts, but these differences were not significant. A lower CD4(+)/CD8(+) ratio at SHCS enrollment or 1 to 2 years before HL diagnosis, however, was significantly associated with increased HL risk. In conclusion, HL risk does not appear to be increasing in recent years or among PHIV using cART in Switzerland, and there was no evidence that HL risk should be increased in the setting of improved immunity.

PD-1, a follicular T-cell marker useful for recognizing nodular lymphocyte-predominant Hodgkin lymphoma

The nodularity and presence of T-cell rosettes surrounding the neoplastic cells has been described as a defining feature of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). We have explored the potential diagnostic value of a new marker (NAT105) that recognizes the antigen PD-1 in a series of 152 cases diagnosed as nodular sclerosis Hodgkin lymphoma, mixed cellularity Hodgkin lymphoma, lymphocyte-rich classic Hodgkin lymphoma, NLPHL, and T-cell/histiocyte-rich B-cell lymphoma (T/HRBCL). All the cases were immunostained with a panel of antibodies against CD10, bcl-6, CXCL13, CD57, and PD-1 (NAT-105). The series includes a set of cases diagnosed as NLPHL with diffuse areas, and a group of borderline cases with features between those of NLPHL and T/HRBCL. Results show that PD-1 (NAT-105) is an excellent immunomarker not only of follicular T-cell rosettes in NLPHL, but also of a subset of lymphocyte-rich classic Hodgkin lymphomas. However, it is not a unique and defining feature of NLPHL. The presence of PD-1-positive (NAT-105) T-cell rosettes seems to be an additional useful feature in the differential diagnosis of NLPHL and T/HRBCL, which is normally a controversial and difficult task. The standard T/HRBCL cases lack follicular T-cell rosettes, whereas most of the borderline cases between the 2 entities have follicular T-cell rosettes, thus suggesting a closer relation with NLPHL.