Cases Of Nodular Lymphocyte Predominant Hodgkin Lymphoma Research Articles

International Prognostic Score for Nodular Lymphocyte-Predominant Hodgkin Lymphoma.

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare cancer, and large international cooperative efforts are needed to evaluate the significance of clinical risk factors and immunoarchitectural patterns (IAPs) for all stages of pediatric and adult patients with NLPHL. Thirty-eight institutions participated in the Global nLPHL One Working Group retrospective study of NLPHL cases from 1992 to 2021. We measured progression-free survival (PFS), overall survival (OS), transformation rate, and lymphoma-specific death rate. We performed uni- and multivariable (MVA) Cox regression stratified by management to select factors for the lymphocyte-predominant international prognostic score (LP-IPS) validated by five-fold cross-validation. We identified 2,243 patients with a median age of 37 years (IQR, 23-51). The median follow-up was 6.3 years (IQR, 3.4-10.8). Most had stage I to II (72.9%) and few B symptoms (9.9%) or splenic involvement (5.4%). IAP was scored for 916 (40.8%). Frontline management included chemotherapy alone (32.4%), combined modality therapy (30.5%), radiotherapy alone (24.0%), observation after excision (4.6%), rituximab alone (4.0%), active surveillance (3.4%), and rituximab and radiotherapy (1.1%). The PFS, OS, transformation, and lymphoma-specific death rates at 10 years were 70.8%, 91.6%, 4.8%, and 3.3%, respectively. On MVA, IAPs were not associated with PFS or OS, but IAP E had higher risk of transformation (hazard ratio [HR], 1.81; P < .05). We developed the LP-IPS with 1 point each for age ≥45 years, stage III-IV, hemoglobin <10.5 g/dL, and splenic involvement. Increasing LP-IPS was significantly associated with worse PFS (HR, 1.52) and OS (HR, 2.31) and increased risk of lymphoma-specific death (HR, 2.63) and transformation (HR, 1.41). In this comprehensive study of all ages of patients with NLPHL, we develop the LP-IPS to identify high-risk patients and inform upcoming prospective clinical trials evaluating de-escalation of therapy for patients with low LP-IPS scores (<2).

Optimizing assessment of CD30 expression in Hodgkin lymphoma by controlling for low expression.

Since the approval of brentuximab vedotin (BV), assessment of CD30 status by immunohistochemistry gained increasing importance in the clinical management of patients diagnosed with CD30-expressing lymphomas, including classical Hodgkin lymphoma (CHL). Paradoxically, patients with low or no CD30 expression respond to BV. This discrepancy may be due to lack of standardization in CD30 staining methods. In this study, we examined 29 cases of CHL and 4 cases of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) for CD30 expression using a staining protocol that was designed to detect low CD30 expression levels, and an evaluation system similar to the Allred scoring system used for breast cancer evaluation. For CHL, 10% of cases had low scores and 3% were CD30 negative, with 3 cases in which the majority of tumor cells showed very weak staining. Unexpectedly, one of four cases of NLPHL was positive. We demonstrate intra-patient heterogeneity in CD30 expression levels and staining patterns in tumor cells. Three CHL cases with weak staining may have been missed without the use of control tissue for low expression. Thus, standardization of CD30 immunohistochemical staining with use of known low-expressing controls may aid in proper CD30 assessment and subsequent therapeutic stratification of patients.

IgD expression in various immunoarchitectural patterns of nodular lymphocyte predominant Hodgkin lymphoma in children

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) consist of lymphocyte predominant cell or LP-cell. Despite their origin from active germinal centers, in some cases LP-cells express IgD, which is characteristic of naive B-lymphocytes of the mantle zone. Due to the rarity of NLPHL, assessing the frequency of IgD-positive cases is difficult. This marker can serve not only for differential diagnosis with other diseases, but also indicate the possible heterogeneity of NLPHL, which is currently represented by six immunoarchitectural patterns. To determine the frequency of IgD-positive cases of NLPHL in children with subsequent assessment of the association with types of immunoarchitectural patterns. The study included 52 cases of NLPHL, which were divided to typical and atypical patterns. Differences between two groups were compared using Fisher's exact tests. IgD expression was found in LP-cells in 26 of 52 cases (50%) and was positively correlated with atypical types (typical - 5/23, 21.7% vs atypical - 21/29, 72.4%, p=0.0003), among which pattern C was most common. Due to the high incidence of IgD-positive cases in NLPHL, this marker may be useful in differential diagnosis with histologic mimics. At the same time, positive IgD status was associated with atypical patterns, which may likely determine the different biology of neoplastic cells within the same form.

Unraveling the Transcriptional Landscape of Nodular Lymphocyte-Predominant Hodgkin Lymphoma and T-Cell/Histiocyte Rich Large B-Cell Lymphoma: Impact of Tumor Microenvironment and Checkpoint Gene Expression

Introduction: Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare B-cell malignancy with a paucity of malignant cells embedded in a diverse tumor microenvironment (TME). The histological composition of the TME is known to influence outcomes, with nodular B-cell rich TME (classical histology, Fan patterns A&amp;B) associated with indolent clinical course, while T-cell infiltration or diffuse growth (variant histology, Fan patterns C-F) may resemble aggressive T/cell-histiocyte rich large B-cell lymphoma (THRLBCL) to which NLPHL can transform. Molecular features of NLPHL and THRLBCL remain to be discovered. To gain further insights into the biology of these lymphomas, we recruited NLPHL and THRLBCL cases as part of the Atlas of Blood Cancer Genomes (ABCG) initiative, a consortium consisting of 26 institutions. Design: We collected comprehensive clinicopathological, treatment and outcome data from 154 NLPHL and 21 THRLBCL patients, with centralized pathology review performed by a panel of dedicated hematopathologists. Fan patterns of the NLPHL samples were documented in all samples where possible. RNA sequencing was performed on formalin-fixed paraffin-embedded (FFPE) diagnostic tumor samples (n=129 NLPHL; n=17 THRLBCL). Tumor-infiltrating immune cell compositions were enumerated using FARDEEP with signature matrix LM22 from CIBERSORT. Results: Median age at diagnosis for the patients with THRLBCL and NLPHL was 54 years (interquartile ratio [IQR] 43-65) and 40 years (IQR 24-53), respectively. The majority of patients with NLPHL had limited stage (74%), whereas the patients with THRLBCL predominantly had advanced stage at diagnosis (95%). In both diseases, most patients were males (NLPHL, 69%; THRLBCL, 76%). Spleen involvement was present in 11 NLPHL patients (8%) and histological growth pattern was documented in 112 patients (73%). Out of those, 47 (42%) presented with variant histology and 65 with classical histology. Variant histology was enriched in NLPHL patients with splenic involvement. During a median follow-up of 6.4 years (IQR 3.8-10.1), 12 NLPHL patients and 9 THRLBCL patients died. Patients with THRLBCL had worse 10-year overall survival (OS, 31% vs 89%; p&amp;lt;0.001) and progression-free survival (PFS, 30% vs 66%; p=0.002) compared to patients with NLPHL. Moreover, NLPHLs with variant histology had inferior 10-year OS compared to NLPHLs with classical histology (81% vs 91%; P=0.03; Figure 1). According to in silico immunophenotyping, THRLBCL cases had the highest median proportions of M1-macrophages (11.0%) and CD8+ T-cells (17.0%), followed by NLPHLs with variant histology (M1-macrophages, 6.5%; CD8+ T-cells, 14.5%), with the lowest proportion observed in NLPHLs with classical histology (M1-macrophages, 5.2%; CD8+ T-cells, 10.9%). In contrast, the median proportions of naïve B cells followed an opposite trend across subtypes (NLPHL classical histology, 15.5%; NLPHL variant histology, 11.0%; THRLBCL, 2.0%), whereas the median proportion of CD4+ T-cells was similar across both lymphomas (NLPHL classical histology, 33.9%; NLPHL variant histology, 33.9%; THRLBCL, 32.4%). Despite differences in the overall transcriptomic landscape, gene expression patterns posited THRLBCL and NLPHL as comprising a biological continuum. THRLBCL shared more similarities with NLPHL with variant histology, while NLPHLs with classical histology exhibited upregulation of genes related to cell growth and proliferation through the MYC pathway (P&amp;lt;0.001). Finally, we identified a strong association between THRLBCL and upregulation of checkpoint genes (P&amp;lt;0.001) and gene expression related to inflammatory response (P&amp;lt;0.001) (Figure 2). Furthermore, NLPHLs with a high checkpoint score (above the 75th percentile) were associated with spleen involvement (P&amp;lt;0.001) and worse outcome (5-year PFS 61% vs 87%; P=0.02). Conclusion: Our study provides the largest comprehensive clinical and transcriptomic analyses of NLPHL and THRLBCL to-date. The findings suggest that the inferior outcomes observed in THRLBCL and in a subset of NLPHL are attributable to a higher degree of inflammation in the TME, increased expression of checkpoint genes, and a high proportion of macrophages.

Specific Polo-Like Kinase 1 Expression in Nodular Lymphocyte-Predominant Hodgkin Lymphoma Suggests an Intact Immune Surveillance Program

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare and relatively indolent B-cell lymphoma. Characteristically, the [lymphocyte-predominant (LP)] tumor cells are embedded in a microenvironment enriched in lymphocytes. More aggressive variants of mature B-cell and peripheral T-cell lymphomas exhibit nuclear expression of the polo-like kinase 1 (PLK1) protein, stabilizing MYC (alias c-myc) and associated with worse clinical outcomes. This study demonstrated expression of PLK1 in the LP cells in 100% of NLPHL cases (n=76). In contrast, <5% of classic Hodgkin lymphoma cases (n=70) showed PLK1 expression within the tumor cells. Loss-of-function approaches demonstrated that the expression of PLK1 promoted cell proliferation and increased MYC stability in NLPHL cell lines. Correlation with clinical parameters revealed that the increased expression of PLK1 was associated with advanced-stage disease in patients with NLPHL. A multiplex immunofluorescence panel coupled with artificial intelligence algorithms was used to correlate the composition of the tumor microenvironment with the proliferative stage of LP cells. The results showed that LP cells with PLK1 (high) expression were associated with increased numbers of cytotoxic and T-regulatory T cells. Overall, the findings demonstrate that PLK1 signaling increases NLPHL proliferation and constitutes a potential vulnerability that can be targeted with PLK1 inhibitors. An active immune surveillance program in NLPHL may be a critical mechanism limiting PLK1-dependent tumor growth.

Microenvironmental immune cell alterations across the spectrum of nodular lymphocyte predominant Hodgkin lymphoma and T-cell/histiocyte-rich large B-cell lymphoma.

The clinicopathological spectrum of nodular lymphocyte predominant Hodgkin lymphoma (NLPHL), also known as nodular lymphocyte predominant B-cell lymphoma, partially overlaps with T-cell/histiocyte-rich large B-cell lymphoma (THRLCBL). NLPHL histology may vary in architecture and B-cell/T-cell composition of the tumour microenvironment. However, the immune cell phenotypes accompanying different histological patterns remain poorly characterised. We applied a multiplexed immunofluorescence workflow to identify differential expansion/depletion of multiple microenvironmental immune cell phenotypes between cases of NLPHL showing different histological patterns (as described by Fan et al, 2003) and cases of THRLBCL. FOXP3-expressing T-regulatory cells were conspicuously depleted across all NLPHL cases. As histology progressed to variant Fan patterns C and E of NLPHL and to THRLBCL, there were progressive expansions of cytotoxic granzyme-B-expressing natural killer and CD8-positive T-cells, PD1-expressing CD8-positive T-cells, and CD163-positive macrophages including a PDL1-expressing subset. These occurred in parallel to depletion of NKG2A-expressing natural killer and CD8-positive T-cells. These findings provide new insights on the immunoregulatory mechanisms involved in NLPHL and THLRBCL pathogenesis, and are supportive of an increasingly proposed biological continuum between these two lymphomas. Additionally, the findings may help establish new biomarkers of high-risk disease, which could support a novel therapeutic program of immune checkpoint interruption targeting the PD1:PDL1 and/or NKG2A:HLA-E axes in the management of high-risk NLPHL and THRLBCL.

ROLE OF GATA3 AND STAT6 IMMUNOHISTOCHEMISTRY IN CLASSIC HODGKIN LYMPHOMA (CHL) AND NODULAR LYMPHOCYTE PREDOMINANT HODGKIN LYMPHOMA (NLPHL)

Objective: The purpose of our study is to investigate the utility of immunohistochemical expression of GATA3 and STAT6 in differentiating Classic Hodgkin Lymphoma (CHL) from Nodular Lymphocyte Predominant Hodgkin Lymphoma (NLPHL). Material and Methods: We approached database of Shaukat Khanum Memorial Cancer Hospital and Research Centre and selected a total of 79 CHLs and 15 NLPHLs diagnosed either on Trucut biopsy or excision biopsy diagnosed during the time 2020-2021. One slide from each of these 94 cases was stained with GATA3 and STAT6 independently and pattern of staining (either nuclear or cytoplasmic or dual nuclear and cytoplasmic) was accessed. Results: 75/79(95%) cases of CHL were positive for GATA3 staining [60/79(75.9%) cases showed nuclear GATA3 staining, 15/79(18.9%) cases showed both nuclear and cytoplasmic staining] and 4/79(5%) CHL cases were negative for GATA3. 15/15(100%) cases of NLPHL were negative for GATA3[12/15(80%) cases showed no staining and 3/15(20%) cases showed only cytoplasmic blush]. 65/79(82%) cases of CHL were positive for STAT6[17/79(21.5%) cases showed nuclear STAT6 expression, 48/79(60.7%) cases showed both nuclear and cytoplasmic staining], and 14/79(18%) cases of CHL were negative for STAT6 expression [8/79(10%) cases showed only cytoplasmic staining and 6/79(8%) showed neither nuclear nor cytoplasmic staining]. 14/15(93.3%) cases of NLPHL were negative for STAT6[5/79(33.3%) cases showed only cytoplasmic staining and 9/15(60%) cases showed no staining] and 1/15(6.7%) case of NLPHL was positive for STAT6[showed nuclear STAT6 staining]. Conclusion: Nuclear staining of GATA3 and STAT6 either alone or in combination with cytoplasmic staining can be used to differentiate CHL from NLPHL. GATA3 effectively excludes NLPHL with 100% negative predictive value. Keywords: GATA3, STAT6, Classic Hodgkin lymphoma, Nodular lymphocyte predominant Hodgkin lymphoma

MEF2B is the ideal immunohistochemical marker to highlight neoplastic LP cells in nodular lymphocyte-predominant Hodgkin lymphoma.

MEF2B is the ideal immunohistochemical marker to highlight neoplastic LP cells in nodular lymphocyte-predominant Hodgkin lymphoma.

Nodular Lymphocyte Predominant Hodgkin Lymphoma with Splenic Involvement Is Characterized By Inflamed Tumor Microenvironment, High Expression of Checkpoint Molecule Gene-Signature and Adverse Outcome

Background: Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare B-cell malignancy characterized by infrequent neoplastic cells embedded in an immunologically active tumor microenvironment (TME). Histologically, NLPHL can be divided into classical (Fan A-B) and variant (Fan C-F) growth patterns. Clinical course is generally indolent, and the majority of patients present with limited stage disease. However, advanced stage with splenic involvement and variant histology are known to be associated with more aggressive disease. The molecular features underlying this association remain unknown. To gain further insights into disease biology, we recruited NLPHL cases as part of the Atlas of Blood Cancer Genomes (ABCG) initiative, a consortium consisting of 26 institutions. Design: We collected comprehensive clinicopathological data including splenic involvement from 135 NLPHL patients, with centralized review performed by a panel of dedicated hematopathologists to ensure accurate diagnosis per 2016 WHO criteria. We performed RNA sequencing on formalin-fixed paraffin-embedded (FFPE) diagnostic tumor lymph nodes (n=100) and enumerated tumor-infiltrating immune cell compositions using FARDEEP with signature matrix LM22 from CIBERSORT. In addition, we performed gene set enrichment analysis to compare molecular pathways between the patients with and without splenic involvement. The Kaplan-Meier method was used to calculate overall survival (OS) and progression free survival (PFS) probabilities, and the log-rank test was used for comparisons between groups. Continuous variables were compared using the Wilcoxon rank-sum test. Results: The median age at diagnosis was 42 years (range 5-80 years). Most patients were males (n=96; 71%) and had limited stage disease (n=96, 74%). Splenic involvement was present in 17 patients (13%). Histologic growth pattern was available for 97 cases, 41 (42%) with variant and 56 (58%) with classical histology. Variant histology was enriched in the patients with splenic involvement. Thirty-five (28%) relapses and 5 (3.9%) transformations occurred during a median follow-up of 80 months (range 0.36-604 months). Ten-year OS and PFS rates for the whole cohort were 86% (95% CI, 78-95%) and 59% (95% CI, 50-71%), respectively. Patients with splenic involvement at diagnosis tended to have inferior outcome at 10 years compared with those without splenic involvement (PFS 40% vs 62%, P=0.129; OS 79% vs 88%, P=0.0553). According to in silico immunophenotyping, NLPHLs with splenic involvement were characterized by a lower proportion of naïve B cells and increased proportions of CD8+ T cells and M1-macrophages compared to the NLPHLs without splenic involvement (P<0.001 for all comparisons). Moreover, splenic involvement was associated with higher expression of checkpoint protein-encoding genes, including PDCD1 (PD-1), CD274 (PD-L1), CTLA4, LAG3, HAVCR2 (TIM-3) and TIGIT (Figure 1; P<0.001). Finally, we found a strong association between splenic involvement and gene expression profile related to inflammatory response (P<0.001), response to interferon gamma (P<0.001) and complement pathways (P<0.001). Conclusion: Our study represents the largest comprehensive clinical and transcriptomic analyses of NLPHL to date. The results demonstrate that NLPHLs with splenic involvement are characterized by inflamed TME with high expression of checkpoint molecule gene-signature and are associated with inferior outcomes. Figure 1. Unsupervised clustering for expression of checkpoint genes stratified by spleen involvement. Samples are ordered by the sum of normalized checkpoint gene expression values (checkpoint score) Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Identification of Nodular Lymphocyte-Predominant Hodgkin Lymphoma Variant Morphology Using Artificial Intelligence

Background Lymphocyte predominant (LP) cells located outside B-cell-rich nodules are the hallmark of variant morphologic patterns of nodular lymphocyte predominant Hodgkin lymphoma (NLPHL). In comparison with typical NLPHL (patterns A and B), cases with variant morpholoy (patterns C, D, E and F) are associated with significantly worse clinical behavior. Nevertheless, assessment of tissue architecture may be challenging in limited biopsy specimens, which are increasingly common in routine clinical practice. We sought to address this gap by developing artificial intelligence-assisted modules to accurately recognize NLPHL and distinguish patterns A/B from variant patterns, namely the most common of those, pattern C. Material & Methods The study group included whole slide images (WSI) of hematoxylin and eosin (H&E) stains and CD20 immunohistochemistry stains from 10 NLPHL patients; cases emcompassed patterns A, B & C (A/B: 5 cases; C: 5 cases) as determined by hematopathology review. We designed modules to assess the spatial relationship between LP cells and B cell-rich areas by first seeking to detect LP cells using high-power field (HPF) magnification of H&E WSI (Figure A1). We split the WSI into tiles (8000 x 8000 pixels) to mitigate the computational burden of WSI analysis. For each tile, we deployed the pretrained HoVer-Net for nuclear segmentation. To distinguish LP cells from surrounding small lymphocytes, we analyzed nuclear size, intensity, and gray-level co-courrance matrix (GLCM) features (correlation and dissimilarity). For each feature, we identified the optimal threshold based on feature histogram of LP in comparison to the remainder surrounding cells. Nuclei meeting all feature criteria were labeled as LP cells and validated morphologically by hematopathologists. All tiles were then stitched to illustrate the spatial distribution of LP cells on WSI. Next we deployed the active contour (AC) technique, an iterative region-growing image segmentation algorithm, to identify B-cell areas from CD20 stains (Figure A2). To reliably define the intial contours for the AC, we abided by the following criteria: 1) Red (R) channel intensity larger than both the green (G) and blue (B) channels, with a ratio of 1.25; 2) Including pixels in the bottom 10% of the intensity histogram after removal of slide background and converting the RGB image into gray scale. We merged the contours from these two techniques and used them as initial seeds for AC segmentation, after which we took the final evolved contour as the boundaries of B-cell areas. We then overlayed CD20 on H&E WSI to assess the spatial relationship between the detected LP cells and B-cell areas. Since tissue sections on the CD20 and H&E slides represent neighboring slices, only translation, rotation, and slight scaling were surmised to occurr between slides in this pilot study set. Accordingly, we employed the affine registration paradigm and optimized mutual information between the transformed CD20 and fixed H&E images until convergence then warped the detected B-cell areas via the obtained deformation field (Figure A3). Results The concordant positioning between two stains after registration allowed us to compare the spatial relationship of LP cells to B-cell areas (including assessment of the number of LP cells inside (922) and outside (639) B-cell areas) (Figure A4). We then segmented the final image into quadrants to simulate needle core biopsies and confirmed the efficiency of our modules in detecting LP cells and analyzing their relationship to B-cell areas in limited tissue, in all quadrants (Figure A5). Our model was successfully applied on 100% of 10 NLPHL cases in this pilot group. After proof of concept was established in a full tissue biopsy sample (Figure A1-5), we applied the same steps to an actual physical needle core biopsy of an NLPHL-pattern C case (Figure B1-3) and were able to identify 7 out of 29 LP cells located outside B-cell areas, in congruence with the previously rendered diagnosis (Figure B4). Conclusion This technique, using H&E staining and CD20 immunohistochemistry only, is especially promising to work-up cases when ordering a routine panel of immunohistochemical stains is not feasible due to limited tissue that may be exhausted. Further validation using an independent cohort is warranted in the future. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Nodular Lymphocyte-predominant Hodgkin Lymphoma With Nodular Sclerosis: An Underrecognized Feature Associated With Pattern D.

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) with unusual features, including some that can overlap morphologically with classic Hodgkin lymphoma (CHL), have been described. Herein, we describe 12 cases of NLPHL with fibrous bands and capsular fibrosis resembling, in part, nodular sclerosis (NS) CHL. Seven of 12 cases harbored Reed-Sternberg-like cells, further suggestive of CHL, but all cases lacked associated eosinophils and/or plasma cells in the background. In this cohort, all cases had areas of so-called pattern D (nodular T-cell rich) as a sole component in 7 (58%) cases or as a hybrid pattern along with pattern E (diffuse T-cell/histiocyte-rich) in 5 (42%) cases. The immunophenotype of the large neoplastic cells in these cases supported their being lymphocyte predominant cells of NLPHL, positive for CD20, CD79a, and OCT2, and negative for CD15 and CD30. However, PAX5 was weak in 9 of 11 cases similar to Hodgkin/Reed-Sternberg cells in CHL. We conclude that some cases of NLPHL are associated with fibrous bands and capsular fibrosis and resemble, in part, NS CHL. In our experience, NLPHL with NS-like features occurs in 10% to 15% of cases of NLPHL and is associated with a variant pattern (D and/or E). In addition, all patients in this cohort were not treated before biopsy, suggesting that the prominent sclerosis in these cases is inherent to disease biology. Recognition of NLPHL with NS-like features further expands the morphologic spectrum of NLPHL and helps avoid potential misdiagnosis as CHL.

The NLPHL Tumor Microenvironment Is Markedly Enriched in the Tigit and PD-1 Signalling Axes Compared to Classical Hodgkin Lymphoma

The NLPHL Tumor Microenvironment Is Markedly Enriched in the Tigit and PD-1 Signalling Axes Compared to Classical Hodgkin Lymphoma

Evolutionary clonal trajectories in nodular lymphocyte-predominant Hodgkin lymphoma with high risk of transformation.

The B-cell architecture of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is complex since it is composed of malignant lymphocyte-predominant cells along with a rich B-cell bystander environment. To gain insight into molecular determinants of disease transformation, we studied B-cell evolutionary trajectories in lymphoma tissue from diagnosis to relapse or transformation to non- Hodgkin lymphoma by next-generation sequencing of immunoglobulin heavy chains. Patients with NLPHL that later transformed were older and showed IgD negativity, absence of the characteristic IGHV3/IGHD3/IGHJ6 lymphocyte-predominant rearrangement and high repertoire clonality. We constructed phylogenetic trees within the compartment of the malignant clone to investigate clonal evolution. In all relapsing cases, the lymphocyte-predominant rearrangement was identical at diagnosis and relapse. NLPHL cases with transformation showed more complex trajectories with strong intraclonal diversification. The dominant founder clone in transformations showed clonal evolution if derived from the same cell of origin, or arose from a different cell of origin. Together, our data point to a significant role of antigenic drive in the transformation of NLHPL and identify high B-cell repertoire clonality with dominant intraclonal lymphocyte-predominant cell diversification as a hallmark of transformation. Sequencing of initial paraffin-embedded tissue may therefore be applied diagnostically to identify NLPHL cases with high risk of transformation.

Lymphocyte predominant Hodgkin lymphoma, antigen-driven after all?

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) was suggested as an entity separate from other types of Hodgkin lymphoma 40 years ago and recognized in the WHO classification in 2001. Based on its relatively benign course with late distant relapses, relation with lymph node hyperplasia with progressively transformed germinal centers, presence of clonal immunoglobulin gene rearrangements with somatic hypermutations and ongoing mutations, and relation with a number of inherited defects affecting the immune system, it has been suspected that NLPHL might be antigen-driven. Recent evidence has shown that cases of IgD-positive NLPHL are associated with infection by Moraxella catarrhalis, a common bacterium in the upper respiratory tract and in lymph nodes. This review summarizes the evidence for NLPHL as a B-cell lymphoma involving follicular T-lymphocytes normally found in germinal centers, its molecular features and relation to inherited immune defects, and its relation and differential diagnosis from similar entities. Finally, it discusses the evidence that in many cases a watch and wait policy might be a viable initial management strategy. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Histopathological and clinical features of nodular lymphocyte-predominant Hodgkin lymphoma and their impact on prognosis: first report from Iran

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare subtype of Hodgkin lymphoma (HL). It shows different histoarchitectural patterns which are reported to be of prognostic significance. This study aimed to investigate the clinicopathological features of NLPHL cases in Shiraz, Iran, and their possible impact on prognosis. Between March 2014 and November 2019, all records for lymphoma were extracted from the electronic files of hospitals affiliated with Shiraz University of Medical Sciences. The slides of all NLPHL cases were extracted and reviewed. Other necessary data was retrieved from hospital records and through direct contact with patients. Among1168 lymphoma cases, 382 were HLs and 19.1% (73) of them were of the NLPHL type. The median age of NLPHL patients was 34 years. Of the patients, 51.5% showed variant patterns, and 11% of them had BM involvement. The variant morphology was significantly associated with BM involvement (p = 0.02). Patients with higher stage tumors had lower OS and PFS rates. Stage, BM involvement, and infra-diaphragmatic involvement were significantly associated with outcomes. The rate of NLPHL and variant morphology seems to be high in our center in Iran. The variant morphology was associated with a higher BM involvement rate but not with OS or PFS. Higher stage, BM, and subdiaphragmatic disease involvement were associated with worse outcomes.

The time to relapse correlates with the histopathological growth pattern in nodular lymphocyte predominant Hodgkin lymphoma

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) can present with different histopathological growth patterns. The impact of these histopathological growth patterns on relapse characteristics is unknown. We therefore analyzed paired biopsies obtained at initial diagnosis and relapse from 33 NLPHL patients who had received first-line treatment within German Hodgkin Study Group (GHSG) trial protocols, and from a second cohort of 41 relapsed NLPHL patients who had been treated outside GHSG studies. Among the 33 GHSG patients, 21 patients presented with a typical growth pattern at initial diagnosis, whereas 12 patients had a variant histology. The histopathological growth patterns at initial diagnosis and at relapse were consistent in 67% of cases. A variant histology at initial diagnosis was associated with a shorter median time to lymphoma recurrence (2.8 vs 5.2 years; P = .0219). A similar tendency towards a shorter median time to lymphoma recurrence was observed for patients presenting with a variant histology at relapse, irrespective of the growth pattern at initial diagnosis. Results obtained from the 41 NLPHL patients who had been treated outside GHSG studies were comparable (median time to lymphoma recurrence for variant histology vs typical growth pattern at initial diagnosis: 1.5 vs 7.0 years). In conclusion, the histopathological growth pattern remains consistent at relapse in the majority of NLPHL cases, and has major impact on the time of relapse.

Primary Extranodal Nodular Lymphocyte Predominant Hodgkin Lymphoma Involving the Thyroid

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is an uncommon lymphoma that accounts for 3-8% of all Hodgkin lymphomas. NLPHL typically presents as early stage disease with localized peripheral lymphadenopathy. Involvement of extranodal sites at the time of presentation occurs in 6% of cases and most commonly involves the spleen, liver, bone marrow, and Waldeyer ring. Primary extranodal NLPHL is exceedingly rare. We describe the first reported case involving the thyroid and review the six other previously described cases of primary extranodal NLPHL.

Experience and Outcome of Patients with Nodular Lymphocyte Predominant Hodgkin Lymphoma (NLPHL) over 8 Years

Introduction: NLPHL is an uncommon variant of Hodgkin lymphoma (HL) accounting for 5% incidence of all HL diagnoses. NLPHL represents a more indolent disease than classical HL, and is therefore managed uniquely. Unlike classical Hodgkin lymphoma (cHL), NLPHL shows CD20 immunoreactivity. Given the rarity of the disease, optimal management is unclear.Here we present our retrospective clinical experience of nine cases of NLPHL diagnosed over the last 8 years at our institution.Results: The median age at diagnosis was 45 years. Eight of the nine patients were males. The youngest patient was 21 years old and the oldest patient at diagnosis was 58 years old. One patient had Stage I, six had stage II and two patients had Stage-III disease. No patient had bone marrow involvement and only two patients had B symptoms. Interestingly, two sets of brothers diagnosed at different intervals were identified among this group of patients.Three out of seven patients with Stage I/II disease received radiation as the primary modality of treatment. Four patients received chemotherapy only and two patients received combined modality treatment( chemotherapy followed by radiation). Only the youngest patient received R-CVP (rituximab, cyclophosphamide, vincristine, and prednisone) to avoid anthracycline related long term toxicity. A total of four patient received R-CHOP, two of these also received involved site radiation therapy (ISRT).One patient received six cycles of AVD (doxorubicin, vincristine and dacarbazine).All the patients achieved complete response (CR) and durable remission except one patient. That particular patient had stage III NLPHL at diagnosis and was treated with R-CHOP initially. Three years later on relapse, he had T-cell rich large B cell lymphoma (TCRBCL) and is currently on a clinical trial with pembrolizumab and remains in complete remission.Conclusions: As has been the experience with other institutions, the majority of the cases of NLPHL at our institution have presented with early stage disease. Treatments have included R-CHOP regimens in most of the cases with durable remission in the majority. Although R-CVP is not the standard regimen for NLPHL, the one young patient who had stage III disease at diagnosis and received R-CVP, achieved CR and remains disease free five years later. This highlights the importance of non-anthracycline chemotherapy regimens as an option for particularly young or older frail patients.NLPHL occurs with higher than expected frequency among first-degree family members of patients with NLPHL as demonstrated in the Finnish Cancer Registry study reported in JCO 2013. Interestingly, in our small cohort, there were two sets of brothers identified with NLPHL, diagnosed metachronously. Unlike cHL, late relapse can occur as well as a propensity to transform to an aggressive B-cell Non-Hodgkin lymphoma. DisclosuresNo relevant conflicts of interest to declare.

A high number of IgG4-positive plasma cells rules out nodular lymphocyte predominant Hodgkin lymphoma.

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is a subtype of Hodgkin lymphoma that frequently shows a nodal growth pattern with abundant reactive B cells in the microenvironment. Early NLPHL cases can be particularly difficult to differentiate from progressively transformed germinal centers (PTGC). Since PTGC have been described to be IgG4 associated in a relatively high proportion of cases, the aim of the present study was to determine if IgG4 immunostaining can be helpful in the differential diagnosis between NLPHL and PTGC. We furthermore aimed to learn if LP cells can express IgG4. For this purpose, 58 cases of PTGC and 56 cases of NLPHL were assessed using IgG4 immunostaining. We could confirm that a significant number of PTGC cases showed high numbers of IgG4-positive plasma cells (22/58, 38%), whereas hot spot areas of IgG4-positive plasma cells were not found in any of the NLPHL cases. In lymph node areas with the differential diagnosis of NLPHL and PTGC, IgG4 immunostaining can therefore provide a helpful diagnostic tool to rule out NLPHL when a high number of IgG4-positive plasma cells are encountered. We also assessed 13 cases with a combination of NLPHL and PTGC in the same lymph node. Five of these cases presented hot spot areas of IgG4-positive plasma cells in the PTGC regions, while no significant numbers of IgG4-positive plasma cells were observed in the NLPHL part of the lymph node. LP cells were never IgG4 positive. Furthermore, immunoglobulin heavy chain rearrangements of single IgG4-positive plasma cells were analyzed, revealing a polyclonal plasma cell population. In summary, our data suggest that IgG4 immunostaining can provide additional information in the diagnostic workup of cases with the differential diagnosis of NLPHL and PTGC. IgG4's inefficiency in clearing antigens may explain why lymph nodes with PTGC are usually strongly enlarged and develop a high number of hyperplastic germinal centers. Polyclonal immunoglobulin heavy chain rearrangements in IgG4-positive plasma cells further support the hypothesis that PTGC represent a misled immune reaction.

Characterization and Purification of Neoplastic Cells of Nodular Lymphocyte Predominant Hodgkin Lymphoma from Lymph Nodes by Flow Cytometry and Flow Cytometric Cell Sorting

We report the flow cytometric (FC) identification and characterization of lymphocyte predominant (LP) cells from tissues involved by nodular lymphocyte predominant Hodgkin lymphoma (NLPHL). First, we immunophenotyped the NLPHL cell line (DEV) confirming a germinal center immunophenotype, lack of expression of CD32 and CD58, and expression of CD54. Nineteen of 26 lymph nodes involved by NLPHL demonstrated a population with an LP immunophenotype (73%), which included expression of germinal center markers (CD75/Bcl-6-positive, CD32-weak/negative without CD10), a B-cell immunophenotype (CD19/CD20/CD40+), IgD and/or IgM expression (67%), and lack of programmed death-ligand 1/ligand 2. The LP cells demonstrated an adhesion macromolecule expression pattern distinct from Hodgkin and Reed-Sternberg cells of classical Hodgkin lymphoma (CHL) (uniform CD50 and variable CD58 for NLPHL; minimal CD50, bright CD58 expression for CHL). A two-tube consensus assay identified LP cells in all seven NLPHL cases examined and only one non-NLPHL case (94 cases evaluated). Finally, FC cell sorting studies confirm that FC-defined populations have an LP cytomorphology. Taken together, these findings demonstrate a two-tube consensus assay can be used to immunophenotype NLHPL with high specificity and sensitivity and rapidly purify LP cells for genetic studies. This study also confirms aneuploidy in LP cells, provides antigens that may be helpful in distinguishing NLPHL from CHL, and suggests that Tcells interact less avidly with LP cells than with Hodgkin and Reed-Sternberg cells.