Biologic features of Hodgkin lymphoma and the development of biologic prognostic factors in Hodgkin lymphoma: tumor and microenvironment

terraFlow, a high-parameter analysis tool, reveals T cell exhaustion and dysfunctional cytokine production in classical Hodgkin's lymphoma

Immune cells express an incredible variety of proteins; by measuring combinations of these, cell types influencing disease can be precisely identified. We developed terraFlow, a platform that defines cell subsets exhaustively by combinatorial protein expression. Using high-parameter checkpoint-focused and function-focused panels, we studied classical Hodgkin's lymphoma (cHL), where systemic T cells have not been investigated in detail. terraFlow revealed immune perturbations in patients, including elevated activated, exhausted, and interleukin (IL)-17+ phenotypes, along with diminished early, interferon (IFN)γ+, and tumor necrosis factor (TNF)+ T cells before treatment; many perturbations remained after treatment. terraFlow identified more disease-associated differences than other tools, often with better predictive power, and included a non-gating approach, eliminating time-consuming and subjective manual thresholds. It also reports a method to identify the smallest set of markers distinguishing study groups. Our results provide mechanistic support for past reports of immune deficiency in cHL and demonstrate the value of terraFlow in immunotherapy and biomarker studies.

Prognostic role of pretreatment 18F-FDG PET/CT and hematological parameters in relapsed/refractory Hodgkin lymphoma patients treated with immune checkpoint inhibitors and chemotherapy: a dual-center cohort study

BACKGROUND

The combination of anti-programmed death-1 antibodies and chemotherapy is effective; however, there are no reliable outcome prediction factors. We investigated the prognostic factors based on 18Fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) quantitative and hematological parameters to predict progression-free survival (PFS) in relapsed/refractory classical Hodgkin lymphoma (R/R cHL) patients treated with immune checkpoint inhibitors (ICIs) and chemotherapy.

METHODS

This retrospective study included 31 patients who underwent 18F-FDG PET/CT before and during treatment. Pretreatment metabolic and hematological parameters were evaluated using Cox regression analysis to identify predictors of PFS. Based on the cut-off values calculated using the receiver operating characteristic (ROC) curve, patients were classified into low-, intermediate-, and high-risk groups. Kaplan-Meier curves and the log-rank test were used to compare survival differences between the groups.

RESULTS

Cox multivariable analysis indicted that the treatment response based on Lactate dehydrogenase (LDH), Lugano classification and SUVmax were independent predictors of PFS (P = 0.004, 0.007 and 0.039, respectively). The optimal cut-off values for SUVmax and LDH were 11.62 and 258.5 U/L, respectively (P < 0.01). Survival curves showed that LDH ≥ 258.5U/L and SUVmax ≥ 11.62 were correlated to shorter PFS (P < 0.001, P = 0.003, respectively). The differences in PFS between the low-, intermediate-, and high-risk groups were statistically significant (P = 0.0043).

CONCLUSION

In R/R cHL patients treated with ICIs and chemotherapy, Lugano classification, SUVmax, and LDH were significantly correlated with PFS. The combination of metabolic and hematological parameters predicts PFS and may help to improve patient selection.

SNPs in genes encoding for IL-10, TNF-α, and NFκB p105/p50 are associated with clinical prognostic factors for patients with Hodgkin lymphoma

Classical Hodgkin lymphoma (cHL) is a B-cell-derived malignant neoplasia that has a unique histological distribution, in which the scarce malignant Hodgkin and Reed-Sternberg cells are surrounded by nonmalignant inflammatory cells. The interactions between the malignant and inflammatory cells are mediated by aberrantly produced cytokines, which play an important role in tumor immunopathogenesis. Single nucleotide polymorphisms (SNPs) in genes encoding cytokines and their regulatory proteins may influence the peripheral levels of these molecules and affect disease’s pathobiology. In this study, we evaluate SNPs in the promoter regions of the genes encoding for two key cytokines in Hodgkin lymphoma: IL-10 (SNP/pIL10–592, rs1800872; and SNP/pIL10–1082, rs1800896) and TNF-α (SNP/pTNF -238, rs361525; and SNP/pTNF -862, rs1800630), as well as an SNP in the intronic region of the NFκB1 gene (SNP/iNFKB1, rs1585215), an important regulator of cytokine gene expression. We then look to their possible association with clinical and laboratory features in cHL patients. Seventy-three patients with cHL are genotyped by qPCR-high resolution melting. The SNPs’ genotypes are analyzed individually for each SNP, and when more than two allelic combinations are identified, the genotypes are also divided into two groups according to proposed biological relevance. By univariate analysis, patients harboring SNP/pTNF -238 AG genotype more frequently have EBV-associated cHL compared to homozygous GG, whereas the presence of mediastinal disease (bulky and nonbulky) is more common in the pIL10–592 AC/CC group compared to the AA homozygous group. Patients with SNP/iNFKB1 AA genotype more frequently have stage IV and extranodal disease at diagnosis. These results indicate that some SNPs’ genotypes for IL-10 and TNF-α genes are associated with prognostic parameters in cHL. For the first time, the SNP/iNFKB1 is described in association with clinical features of the disease.

Ipilimumab, nivolumab, and brentuximab vedotin combination therapies in patients with relapsed or refractory Hodgkin lymphoma: phase 1 results of an open-label, multicentre, phase 1/2 trial

BACKGROUND

Recognising that the immune suppressive microenvironment promotes tumour growth in Hodgkin lymphoma, we hypothesised that activating immunity might augment the activity of targeted chemotherapy. We evaluated the safety and activity of combinations of brentuximab vedotin with nivolumab or ipilimumab, or both in patients with relapsed or refractory Hodgkin lymphoma.

METHODS

In this multicentre, open-label, phase 1/2 trial, patients with relapsed or refractory Hodgkin lymphoma aged 18 years or older who had relapsed after at least one line of therapy, with an Eastern Cooperative Oncology Group performance status of 2 or lower, and adequate organ and marrow function, with no pulmonary dysfunction were eligible for inclusion. Phase 1 primary objectives were to determine the maximum tolerated dose and dose limiting toxicities of brentuximab vedotin combined with ipilimumab (ipilimumab group), nivolumab (nivolumab group), or both (triplet therapy group) using a 3 + 3 dose escalation design with expansion cohorts. During the dose escalation phase, patients were enrolled sequentially into one of six cohorts: in the ipilimumab group fixed brentuximab vedotin 1·8 mg/kg with ipilimumab 1 mg/kg (cohort A) or 3 mg/kg (cohort B); in the nivolumab group fixed nivolumab 3 mg/kg with brentuximab vedotin 1·2 mg/kg (cohort D) or 1·8 mg/kg (cohort E); and in the triplet therapy group fixed nivolumab 3 mg/kg and ipilimumab 1 mg/kg with brentuximab vedotin 1·2 mg/kg (cohort G) or 1·8 mg/kg (cohort H). Additional patients were enrolled in the expansion phase at the same doses of cohorts B, E, and H. All drugs were given intravenously; brentuximab vedotin and nivolumab were given every 3 weeks, ipilimumab was given every 6 weeks in the ipilimumab group and every 12 weeks in the triplet therapy group. All eligible and treated patients were included in the analysis. This phase 1/2 study is registered with ClinicalTrials.gov, NCT01896999. The phase 2, randomised portion of the trial is still enrolling.

FINDINGS

Between March 7, 2014, and Dec 28, 2017, 64 patients were enrolled; two patients in the ipilimumab group and one patient in the nivolumab group were excluded due to ineligibility after enrolment and 61 were evaluable. A total of six dose limiting toxicities were reported in four patients, and the doses used in cohorts B, E, and H were established as maximum tolerated doses and patients were subsequently enrolled onto expansion cohorts (C, F, and I) with these schedules. There were ten (43%) grade 3-4 treatment related adverse events in the ipilimumab group, three (16%) in the nivolumab group, and 11 (50%) in the triplet therapy group including: eight (13%) of 64 patients reporting rash, and colitis, gastritis, pancreatitis and arthritis, and diabetic ketoacidosis each occurring in one (2%) patient. There were two (3%) treatment related deaths, one in the nivolumab group and one in the triplet therapy group. The overall response rate was 76% (95% CI 53-92) in the ipilimumab group, 89% (65-99) in the nivolumab group, and 82% (60-95) in the triplet therapy group, and the complete response rate was 57% (95% CI 34-78%) in the ipilimumab group, 61% (36-83%) in the nivolumab group, and 73% (50-89%) in the triplet therapy group. With a median follow-up of 2·6 years (IQR 1·8-2·9) in the ipilimumab group, 2·4 years (2·2-2·6) in the nivolumab group, and 1·7 years (1·6-1·9) in the triplet therapy group, median progression-free survival is 1·2 years (95% CI 1·7-not reached) in the ipilimumab group, but was not reached in the other two treatment groups. Median overall survival has not been reached in any of the groups.

INTERPRETATION

There are clear differences in activity and toxicity of the three combination regimens. The tolerability and preliminary activity for the two most active regimens, brentuximab vedotin with nivolumab and the triplet therapy, are being compared in a randomised phase 2 trial (NCT01896999).

FUNDING

Eastern Cooperative Oncology Group-American College of Radiology Imaging Network and the National Cancer Institute of the National Institutes of Health.

PD-1 blockade in Hodgkin's lymphoma: learning new tricks from an old teacher

INTRODUCTION

Classical Hodgkin's Lymphoma (cHL) is characterized by genetic reliance on the PD-1 pathway. Rapid accumulation of data describing the role and efficacy of PD-1 and its blockade warrants a focused review.

AREAS COVERED

In this article, we will review the unique biologic features that predispose cHL to PD-1 inhibition, current data regarding the safety and efficacy of PD-1 inhibitors in the treatment of cHL, biomarkers of immune response, ongoing clinical trials with PD-1 inhibitors, as well as areas of uncertainty. Expert commentary: The biologic and genetic underpinnings of cHL make it unique among all malignancies in its exquisite sensitivity to PD-1 inhibition. High response rates to single agent PD-1 inhibitors in early phase clinical trials serve as further proof of concept. These data strongly support continued clinical investigation of the evolving role of PD-1 inhibition in classical Hodgkin's lymphoma, including the optimal sequence, setting, and combination to best exploit the immunologic properties of this disease.

Customized targeted therapy in Hodgkin lymphoma: hype or hope?

Although most patients with Hodgkin lymphoma (HL) are cured with primary therapy, patients with primary refractory disease or relapse after initial treatment have poor outcomes and represent an unmet medical need. Recent advances in unraveling the biology of HL have yielded a plethora of novel targeted therapies. This review provides an overview of the data behind the hype generated by these advances and addresses the question of whether or not clinically these targeted therapies offer hope for patients with HL.

Hodgkin lymphoma: pathology, pathogenesis, and a plethora of potential prognostic predictors

Hodgkin lymphoma (HL) encompasses 2 unique clinicopathologic entities, classical Hodgkin lymphoma (CHL) (∼95% of cases) and nodular lymphocyte predominant HL (∼5% of cases). Both subtypes demonstrate a paucity of surreptitious (in CHL) neoplastic B cells within a background of reactive inflammatory cells underscoring both the relatedness of these 2 entities to each other, as well as their distinction from other types of lymphoid neoplasia. Clinically, they are primarily nodal diseases that disseminate in a predictable manner to contiguous nodal regions. The biology of HL as a whole, as well as the genetic and pathologic features that distinguish CHL from nodular lymphocyte predominant HL and other lymphomas has been the subject of a wealth of investigation in recent decades. The aim of this review is to detail the pathologic features of HL and to highlight the recent insights into its molecular basis and the myriad prognostic markers being described.

Immunologic pathomechanism of Hodgkin's lymphoma

Hodgkin's lymphoma is a lymphoid malignancy of the immune system. The pathognomonic Hodgkin and Reed-Sternberg cells (HRS) are derived mainly from monoclonal, preapoptotic B cells, and they carry rearranged, somatically mutated immunoglobulin heavy chains. In an appropriate microenvironment, HRS cells escape from apoptosis by several mechanisms, including single mutations, aberrant signaling pathways. Eventually, weakened immune surveillance leads to uncontrolled, disproportional B cell proliferation. This review summarizes the latest findings on the pathogenesis of Hodgkin lymphoma, with a special emphasis on immunologic processes, and depicts current and future immunotherapeutic regimens, which improve treatment outcomes and reduce late toxicities.

Cytokine gene polymorphisms and progression-free survival in classical Hodgkin lymphoma by EBV status: results from two independent cohorts

BACKGROUND

Cytokines are important immune mediators of classical Hodgkin lymphoma (CHL) pathogenesis, and circulating levels at diagnosis may help predict prognosis. Germline single nucleotide polymorphisms (SNPs) in immune genes have been correlated with cytokine production and function.

METHODS

We investigated whether selected germline SNPs in IL10 (rs1800890, rs1800896, rs1800871, rs1800872), TNFA (rs1800629), IL6 (rs1800795), ILRN (rs419598), INFG (rs2430561) and CCL17 (rs223828) were associated with circulating levels of related cytokines at diagnosis and progression-free survival (PFS) in CHL. Patients were from France (GELA, N=464; median age=32years) and the United States (Iowa/Mayo Specialized Program Of Research Excellence [SPORE], N=239; median age=38years); 22% of 346 CHL cases with EBV tumor status were positive.

RESULTS

There was no association with any of the SNPs with cytokine levels. Overall, there was no association of any of the SNPs with PFS. In exploratory analyses by EBV status, TNFA rs1800629 (HRAA/AG=2.41; 95%CI, 1.17-4.94) was associated with PFS in EBV-negative GELA patients, with similar trends in the SPORE patients (HRAA/AG=1.63; 95%CI, 0.61-4.40). In a meta-analysis of the two studies, TNFA (HRAA/AG=2.11; 95%CI, 1.18-3.77; P=0.01) was statistically significant, and further adjustment for the international prognostic system did not alter this result.

CONCLUSIONS

This study showed that germline variation in TNFA was associated with CHL prognosis for EBV-negative patients, which will require confirmation. These results support broader studies on the differential impact of genetic variation in immune genes on EBV-positive vs. EBV-negative CHL pathogenesis.

CD163 and c-Met expression in the lymph node and the correlations between elevated levels of serum free light chain and the different clinicopathological parameters of advanced classical Hodgkin's lymphoma

BACKGROUND

Advances in the understanding of Hodgkin's lymphoma (HL) show various functions of infiltrating immune cells and cytokines in relation to clinical outcomes. The expression of CD163 and c-Met has been suggested to have a role in lymphoid malignancy. Thus, we evaluated the expressions of CD163, c-Met, and serum free light chain (sFLC) in relation to the clinicopathological features of patients with advanced classical HL (cHL).

METHODS

We assessed the expression of CD163 and c-Met in 34 patients with cHL through immunohistochemistry on the lymph node biopsy sections and the levels of pretreatment sFLC were estimated using ELISA.

RESULTS

High CD163 expression correlated with increased age, B symptoms, International Prognostic Score (IPS) ≥3, mixed cellularity subtype, and low response to treatment. Further, high c-Met expression correlated with increased age at diagnosis, leukocytosis, B symptoms, and lower chance to achieve complete remission. The sFLC levels correlated with increased age at diagnosis, lymphopenia, IPS ≥3, B symptoms, and lower complete remission rates.

CONCLUSION

In advanced cHL, increased expression of CD163 and c-Met showed a significant association with adverse prognostic parameters and poor response to treatment. Pretreatment high sFLC level also correlated with poor risk factors, suggesting its use as a candidate prognostic marker. A comprehensive approach for prognostic markers might represent a step towards developing a tailored therapeutic approach for HL.

New strategies in Hodgkin lymphoma: better risk profiling and novel treatments

Recent advances in Hodgkin lymphoma research are expected to prelude a promising new treatment era for patients and their treating physicians. Scientific investigations over the last few years have provided new insights into risk stratification, and, simultaneously, a plethora of novel targeted therapies are emerging for patients with relapsed and refractory disease. These novel therapies will be tested primarily in high-risk patients because 75% of the patients are cured with conventional therapies. The challenges, as Hodgkin lymphoma therapy moves forward, will be using these biologic insights to identify the patients who may benefit earlier in treatment from these novel agents, and tailoring the therapy to the tumor biology of the patient. These dual aims are intertwined; as our therapeutic arsenal increases, these biologic determinants of risk may themselves inform the design of therapies and the choice of treatments for high-risk patients.

MiR-SNPs as markers of toxicity and clinical outcome in Hodgkin lymphoma patients

Background

In recent years, microRNA (miRNA) pathways have emerged as a crucial system for the regulation of tumorogenesis. miR-SNPs are a novel class of single nucleotide polymorphisms that can affect miRNA pathways.

Design and Methods

We analyzed eight miR-SNPs by allelic discrimination in 141 patients with Hodgkin lymphoma and correlated the results with treatment-related toxicity, response, disease-free survival (DFS) and overall survival (OS).

Results

The KRT81 (rs3660) GG genotype was associated with an increased risk of neurological toxicity (P = 0.016), while patients with XPO5 (rs11077) AA or CC genotypes had a higher rate of bleomycin-associated pulmonary toxicity (P = 0.048). Both miR-SNPs emerged as independent factors in the multivariate analysis. The XPO5 AA and CC genotypes were also associated with a lower response rate (P = 0.036). XPO5 (P = 0.039) and TRBP (rs784567) (P = 0.022) genotypes emerged as prognostic markers for DFS, and XPO5 was also associated with OS (P = 0.033). In the multivariate analysis, only XPO5 emerged as an independent prognostic factor for DFS (HR: 2.622; 95%CI 1.039–6.620; P = 0.041). Given the influence of XPO5 and TRBP as individual markers, we then investigated the combined effect of these miR-SNPs. Patients with both the XPO5 AA/CC and TRBP TT/TC genotypes had the shortest DFS (P = 0.008) and OS (P = 0.008).

Conclusion

miR-SNPs can add useful prognostic information on treatment-related toxicity and clinical outcome in Hodgkin lymphoma and can be used to identify patients likely to be chemoresistant or to relapse.

Galectin-1 serum levels reflect tumor burden and adverse clinical features in classical Hodgkin lymphoma

Galectin-1 (Gal1) is a member of a highly conserved family of carbohydrate-binding proteins. It modulates innate and adaptive immune responses and fosters tumor-immune escape. Hodgkin lymphoma (HL) Reed-Sternberg cells overexpress and secrete Gal1, which selectively kills T helper (Th)1 and Th17 cells and cytotoxic T cells and promotes the immunosuppressive Th2/regulatory T-cell-predominant HL microenvironment. We developed a sandwich enzyme-linked immunosorbent assay and assessed serum Gal1 levels in 293 newly diagnosed, previously untreated patients with classical HL (cHL) enrolled in 3 risk-adapted clinical trials. Serum Gal1 levels were significantly higher in patients with cHL than in normal controls (P < .0001). Gal1 serum levels also increased with Ann Arbor stage (P = .012), areas of nodal involvement (P < .0001), and the International Prognostic Score (2-7, P = .019). We conclude that Gal1 serum levels are significantly associated with tumor burden and related clinical features in newly diagnosed cHL patients.

Detection of ABCC1 expression in classical Hodgkin lymphoma is associated with increased risk of treatment failure using standard chemotherapy protocols

BACKGROUND

The mechanisms responsible for chemoresistance in patients with refractory classical Hodgkin lymphoma (CHL) are unknown. ATP-binding cassette (ABC) transporters confer multidrug resistance in various cancers and ABCC1 overexpression has been shown to contribute to drug resistance in the CHL cell line, KMH2.

FINDINGS

We analyzed for expression of five ABC transporters ABCB1, ABCC1, ABCC2, ABCC3 and ABCG2 using immunohistochemistry in 103 pre-treatment tumor specimens obtained from patients with CHL. All patients received first-line standard chemotherapy with doxorubicin (Adriamycin®), bleomycin, vinblastine, and dacarbazine (ABVD) or equivalent regimens. ABCC1 was expressed in Hodgkin and Reed-Sternberg (HRS) cells in 16 of 82 cases (19.5%) and ABCG2 was expressed by HRS cells in 25 of 77 cases (32.5%). All tumors were negative for ABCB1, ABCC2 and ABCC3. ABCC1 expression was associated with refractory disease (p = 0.01) and was marginally associated with poorer failure-free survival (p = 0.06). Multivariate analysis after adjusting for hemoglobin and albumin levels and age showed that patients with CHL with HRS cells positive for ABCC1 had a higher risk of not responding to treatment (HR = 2.84, 95%, CI: 1.12-7.19 p = 0.028).

CONCLUSIONS

Expression of ABCC1 by HRS cells in CHL patients predicts a higher risk of treatment failure and is marginally associated with poorer failure-free survival using standard frontline chemotherapy regimens.

Expression of COX-2 on Reed-Sternberg cells is an independent unfavorable prognostic factor in Hodgkin lymphoma treated with ABVD

Cyclooxygenase 2 (COX-2) is an inflammatory enzyme involved in the pathogenesis and prognosis of several malignancies. In the present study, we investigated the prognostic value of COX-2 expression in a large (N = 242), uniformly treated Hodgkin lymphoma (HL) population from the Spanish Network of HL using tissue microarrays. Univariate and multivariate analysis was done, including comparing the most recognized clinical variables: the early- and advanced-stage subgroups. COX-2 was expressed on Reed-Sternberg cells in 37% of patients. There were no differences in the distribution of clinical variables according to COX-2 expression. With a median follow-up time of 58 months, PFS at 5 years was 60% and 79% for COX-2+ and COX-2− patients, respectively (P = .003). The overall survival was 73% and 91%, respectively (P < .001). The major impact on prognosis was observed in the early AA stage (I-II) group. In fact, in these low-risk groups the expression of COX-2 defined a group with significantly worse progression-free and overall survival. In conclusion, COX-2 was expressed on Reed-Sternberg cells in one-third of HL patients and was a major independent, unfavorable prognostic factor in early-stage HL. We conclude that COX-2 may be a major prognostic variable in HL and a potential therapeutic target.

Lack of association of tumor-associated macrophages with clinical outcome in patients with classical Hodgkin's lymphoma

BACKGROUND

A recent study demonstrated that an increased number of CD68+ macrophages were correlated with primary treatment failure, shortened progression-free survival (PFS) and disease-specific survival (DSS) in patients with classical Hodgkin's lymphoma (cHL).

PATIENTS AND METHODS

The aim of the present study was to verify the relationship between the number of CD68+ and CD163+ macrophages with clinical outcomes in a cohort of 265 well-characterized patients with cHL treated uniformly with the standard doxorubicin, bleomycin, vinblastine and dacarbazine chemotherapy regimen. Two pairs of hematopathologists carried out independent pathological evaluations of tissue microarray slides.

RESULTS

There were no associations between clinical characteristics and the expression of CD68 or CD163. However, higher levels of CD68 and CD163 expression were correlated with the presence of Epstein-Barr virus-positive Hodgkin tumor cells (P = 0.01 and 0.037, respectively). The expression of CD68 or CD163 was not associated with either the PFS or the DSS.

CONCLUSION

CD68 and CD163 expression require further evaluation before their use can be recommended for prognostic stratification of patients with cHL.

The role of CD40/CD40L and interferon regulatory factor 4 in Hodgkin lymphoma microenvironment

Inflammation and cancer are two independent biological events that can play an interdependent role. The model of such interaction is represented by Hodgkin lymphoma (HL), where the microenvironment is dominated by an extensive mixed, potentially cellular inflammatory infiltrate that plays a decisive role in the pathobiology of HL. In this review we summarize updated information on the complex interactions between Hodgkin Reed-Sternberg (HRS) cells and their tissue microenvironment, highlighting the functional role of CD40/CD40L and interferon regulatory factor 4 (IRF4).

Predictors of histology, tissue eosinophilia and mast cell infiltration in Hodgkin's lymphoma--a population-based study

OBJECTIVE

Classical Hodgkin's lymphoma (HL) lesions comprise few tumour cells, surrounded by numerous inflammatory cells. Like in other malignancies, the microenvironment is presumed to be clinically important in HL; however, microenvironment predictors remain poorly characterised. The aim of this study was to investigate how selected patient characteristics and genetic factors affect HL phenotype, in particular tissue eosinophilia, mast cell counts and HL histological subtype.

METHODS

In a population-based study, patients with HL were interviewed about potential HL risk factors. Available tumours, n=448, were classified histologically; the number of eosinophils and mast cells were estimated, and eosinophil cationic protein (ECP) and eosinophil protein-x (EPX) gene polymorphisms were determined. Associations were assessed in regression models.

RESULTS

Self-reported history of asthma was predictive of having tumour eosinophilia [≥200 eosinophils/10 high power fields, univariate odds ratio (OR)=2.22, 95% CI 1.06-4.64, P=0.03]. High numbers of eosinophils were predominantly seen in patients carrying the genotype ECP434GG [multivariate relative levels (RLs)=1.84, 95% CI 1.02-3.30, P=0.04]. Lower number of eosinophils was seen in Epstein-Barr virus (EBV)-positive tumours (univariate RL=0.52, 95% CI 0.3-0.9, P=0.02) and in older patients (univariate RL=0.85, 95% CI 0.73-0.99, P=0.03). Well-known factors such as young age, female sex and EBV-negative status predicted nodular sclerosis histology.

CONCLUSION

The number of eosinophils in HL tumours is influenced by patient traits such as asthma, ECP genotype and EBV status. EBV status was predictive of histology.

Current concepts and controversies in the management of early stage Hodgkin lymphoma

Over the past three decades, due to the recognition of late effects related to high-dose extended field radiotherapy and heavy alkylator chemotherapy, combined modality therapy with abbreviated chemotherapy and limited field radiotherapy has emerged as the standard of care for early stage Hodgkin lymphoma, with cure rates in excess of 80%. Currently, however, controversy remains over identifying the most appropriate criteria to risk-stratify patients with early stage disease, so that those with a favorable prognosis receive limited treatment without compromising cure rates and those with unfavorable risk receive more intensified therapy. The optimal risk stratification system remains unclear, with variable definitions of favorable and unfavorable disease used by research groups in North America and Europe. Thus, comparison of clinical trial results has been challenging, and additional controversies persist regarding optimal chemotherapy regimens, duration of therapy, and the role of radiotherapy. Investigations are ongoing to assess the potential of functional imaging and biomarkers as tools for risk stratification. The collective goal is to further refine current stratification strategies to allow for an individualized, risk-adapted treatment approach that minimizes long-term late effects without compromising high cure rates.

Prognostic biomarkers in malignant lymphomas

There has recently been a rapid expansion in research aimed at identifying biomarkers that could improve the prognosis for patients with various subtypes of malignant lymphoma. Genomic and genetic studies have led to the identification of biological and clinical subgroups of diffuse large B-cell lymphomas with distinct underlying molecular features, divergent activation of oncogenetic pathways, and clinical course. Molecular studies of follicular lymphoma have suggested complex interactions between malignant cells and the surrounding immunological network that could affect disease progression. Moreover, the inflammatory cells of Hodgkin lymphoma have been shown to produce a complex network of cytokines and chemokines that provide a permissive microenvironment for tumor growth. Research into specific biomarkers and signaling pathways of malignant lymphomas might therefore result in the identification of novel targets for future therapeutic strategies. As gene expression profiling techniques are not yet feasible in the clinical laboratory, studies have aimed to translate the findings into more widely applicable techniques that might allow this research to be applied to routine clinical practice. This review focuses on recent advances in translational and clinical research on biomarkers in malignant lymphomas.

Hodgkin's and non-Hodgkin's lymphomas occurring in two brothers with Wiskott-Aldrich syndrome and review of the literature

Approximately 13% of patients with Wiskott-Aldrich syndrome (WAS), a primary immune deficiency, develop malignant tumors, the predominant form being non-Hodgkin's lymphoma. Previously, only 4 cases of Hodgkin's lymphoma have been reported in WAS patients. Herein, we review the literature of WAS-related lymphomas and report 2 brothers with WAS who both developed lymphomas; one developed Epstein-Barr virus (EBV)-driven diffuse large B-cell lymphoma, and one developed EBV-negative classical Hodgkin's lymphoma. In contrast to many of the previously reported lymphomas in WAS patients, these lymphomas were extensively evaluated by means of molecular, flow cytometric, and immunohistochemical methods. Both brothers died shortly after diagnosis, despite aggressive therapy. The occurrence of 2 distinct forms of lymphomas in these brothers underscores the interplay between genetic susceptibility and environmental exposure in lymphoma pathogenesis.

Prognostication and Risk-Adapted Therapy of Hodgkin's Lymphoma Using Positron Emission Tomography

The use of ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) for response assessment in lymphoma is now widespread. Prognostic information obtained from PET performed after two to three cycles of chemotherapy may guide more individualized, risk-adapted therapeutic strategies. Progress in the risk stratification of Hodgkin's lymphoma through midtreatment PET is reviewed, with a focus on management implications in newly diagnosed and relapsed disease. How to tailor treatment on the basis of the interim PET result is not yet defined but is the subject of ongoing trials.

Hodgkin's Lymphomas: A Tumor Recognized by Its Microenvironment

Thomas Hodgkin's and Samuel Wilks first recognized Hodgkin disease in the first half of the 19th century. Initially described as lymphogranulomatosis, it was later recognized to be a lymphoid neoplasm derived from B cells and was classified on the basis of its histopathological features. Hodgkin lymphomas are now regarded as encompassing two clearly defined entities according to the WHO classification: nodular lymphocyte-predominant Hodgkin Lymphoma (NLPHL) and classical Hodgkin Lymphoma (CHL). This paper focuses on the current knowledge about the biological features that characterize both NLPHL and CHL, highlighting those relevant to correct pathological diagnosis and those that might be associated with patient outcome.

Human germinal center-associated lymphoma protein expression is associated with improved failure-free survival in Brazilian patients with classical Hodgkin lymphoma

The human germinal center-associated lymphoma (HGAL) gene has prognostic value in diffuse large B-cell lymphoma, and expression of its cognate protein is germinal center-specific. A previous study had suggested that HGAL protein expression might also be related to the outcome in patients with Hodgkin lymphoma (HL). The aim of this study was to confirm the prognostic impact of HGAL protein expression in an independent, well-characterized cohort of 232 patients with classic HL treated uniformly with doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD). Tissue microarray analysis showed HGAL staining in 188 specimens (81%). Failure-free survival (FFS) was superior in patients with early-stage disease, low-risk IPS, and HGAL-positive patients. The estimated 5-year FFS for HGAL-positive and HGAL-negative patients was 82% and 67%, respectively (p = 0.03). In the multivariate analysis, advanced stage and absence of HGAL staining were independent predictors of a worse FFS. This study confirms and validates recent findings of a correlation between HGAL expression and outcome in classical HL.

Upcoming diagnostic and therapeutic developments in classical Hodgkin's lymphoma

With improvements in therapy, increasing dose intensity, early recognition of toxicity, and enhanced supportive care, current outcomes in patients with classical Hodgkin's lymphoma (HL) may be superior to disease-free and overall survival (OS) predicted by existing prognostic models, including the International Prognostic Score (IPS). The addition of biologic markers to recognized clinical prognostic factors, including those of the IPS, may to improve patient risk stratification and guide therapy in the future. However, the identification of these markers has been problematic due to the lack of large, confirmatory prospective trials, reproducibility and feasibility of the assays, and failure to improve upon already recognized clinical risk factors. One biomarker in particular, CD68, present on tumor infiltrating macrophages and detectable by immunohistochemical staining, is significantly associated with both shortened progression-free and disease-specific survivals in patients with HL at diagnosis and at relapse. In addition, less than 5% CD68+ cells correlates with a 100% disease-specific survival in patients with early-stage HL. CD68 represents just one of the many prognostic markers that could eventually be used to risk-stratify therapy. In addition, biologic markers may not only serve as prognostic markers, but also as therapeutic targets in HL. This review examines current data using the IPS to determine patient outcome, discuss several potential biologic prognostic markers, and summarize new therapies that are currently in clinical development in HL.

Regulation of JAK2 by miR-135a: prognostic impact in classic Hodgkin lymphoma

The behavior of classic Hodgkin lymphoma (cHL) is determined by both the intrinsic features of the tumor cells and the characteristics of the microenvironment, making the analysis of entire lymph nodes an effective approach to understanding the disease. We examined the influence of our previously reported 25-microRNA signature for cHL on clinical outcome in 89 homogeneously treated cHL patients with a median follow-up of 80 months. Patients with low miR-135a expression had a higher probability of relapse (P = .04) and a shorter disease-free survival (P = .02). Functional analysis of cHL cell lines showed that mature miR-135a levels increased after pre–miR-135a transfection, causing apoptosis and decreased cell growth. Target analysis showed a direct regulation by miR-135a of JAK2, a cytoplasmic tyrosine kinase involved in a specific subset of cytokine receptor signaling pathways. miR-135a–mediated JAK2 down-regulation led to decreased mRNA and protein levels of the antiapoptotic gene Bcl-xL, suggesting a role for Bcl-xL in miR-135a/JAK2–mediated apoptosis. Our findings confirm the critical role of miR-135a in the survival of cHL cells and in the prognosis of cHL patients, indicating that novel treatment approaches targeting miR-135a may potentially benefit these patients.

Clinical significance of interleukin-10 gene polymorphisms and plasma levels in Hodgkin lymphoma

We studied plasma levels of IL-10 and five single nucleotide polymorphisms in the interleukin-10 (IL-10) gene promoter in patients with Hodgkin lymphoma (HL) to address potential genotype-phenotype correlations. Patients with elevated IL-10 levels were more likely to have advanced stage disease and inferior event-free survival. Homozygous carriers of the variant alleles at position -592 (AA) and -1082 (GG) of the IL-10 promoter had higher IL-10 plasma levels, independent of male gender and advanced stage of disease which also determined increased IL-10 production. This analysis indicates that the genetic background can modulate plasma levels of IL-10, and ultimately prognosis in HL.