Spatially Resolved Tumor Microenvironment Predicts Treatment Outcomes in Relapsed/Refractory Hodgkin Lymphoma

PURPOSE

About a third of patients with relapsed or refractory classic Hodgkin lymphoma (r/r CHL) succumb to their disease after high-dose chemotherapy followed by autologous stem-cell transplantation (HDC/ASCT). Here, we aimed to describe spatially resolved tumor microenvironment (TME) ecosystems to establish novel biomarkers associated with treatment failure in r/r CHL.

PATIENTS AND METHODS

We performed imaging mass cytometry (IMC) on 71 paired primary diagnostic and relapse biopsies using a marker panel specific to CHL biology. For each cell type in the TME, we calculated a spatial score measuring the distance of nearest neighbor cells to the malignant Hodgkin Reed Sternberg cells within the close interaction range. Spatial scores were used as features in prognostic model development for post-ASCT outcomes.

RESULTS

Highly multiplexed IMC data revealed shared TME patterns in paired diagnostic and early r/r CHL samples, whereas TME patterns were more divergent in pairs of diagnostic and late relapse samples. Integrated analysis of IMC and single-cell RNA sequencing data identified unique architecture defined by CXCR5+ Hodgkin and Reed Sternberg (HRS) cells and their strong spatial relationship with CXCL13+ macrophages in the TME. We developed a prognostic assay (RHL4S) using four spatially resolved parameters, CXCR5+ HRS cells, PD1+CD4+ T cells, CD68+ tumor-associated macrophages, and CXCR5+ B cells, which effectively separated patients into high-risk versus low-risk groups with significantly different post-ASCT outcomes. The RHL4S assay was validated in an independent r/r CHL cohort using a multicolor immunofluorescence assay.

CONCLUSION

We identified the interaction of CXCR5+ HRS cells with ligand-expressing CXCL13+ macrophages as a prominent crosstalk axis in relapsed CHL. Harnessing this TME biology, we developed a novel prognostic model applicable to r/r CHL biopsies, RHL4S, opening new avenues for spatial biomarker development.

Novel anti-CD30/CD3 bispecific antibodies activate human T cells and mediate potent anti-tumor activity

CD30 is expressed on Hodgkin lymphomas (HL), many non-Hodgkin lymphomas (NHLs), and non-lymphoid malignancies in children and adults. Tumor expression, combined with restricted expression in healthy tissues, identifies CD30 as a promising immunotherapy target. An anti-CD30 antibody-drug conjugate (ADC) has been approved by the FDA for HL. While anti-CD30 ADCs and chimeric antigen receptors (CARs) have shown promise, their shortcomings and toxicities suggest that alternative treatments are needed. We developed novel anti-CD30 x anti-CD3 bispecific antibodies (biAbs) to coat activated patient T cells (ATCs) ex vivo prior to autologous re-infusions. Our goal is to harness the dual specificity of the biAb, the power of cellular therapy, and the safety of non-genetically modified autologous T cell infusions. We present a comprehensive characterization of the CD30 binding and tumor cell killing properties of these biAbs. Five unique murine monoclonal antibodies (mAbs) were generated against the extracellular domain of human CD30. Resultant anti-CD30 mAbs were purified and screened for binding specificity, affinity, and epitope recognition. Two lead mAb candidates with unique sequences and CD30 binding clusters that differ from the ADC in clinical use were identified. These mAbs were chemically conjugated with OKT3 (an anti-CD3 mAb). ATCs were armed and evaluated in vitro for binding, cytokine production, and cytotoxicity against tumor lines and then in vivo for tumor cell killing. Our lead mAb was subcloned to make a Master Cell Bank (MCB) and screened for binding against a library of human cell surface proteins. Only huCD30 was bound. These studies support a clinical trial in development employing ex vivo-loading of autologous T cells with this novel biAb.

A ciprofloxacin derivative with four mechanisms of action overcomes paclitaxel resistance in p53-mutant and MDR1 gene-expressing type II human endometrial cancer

Dysfunction of the p53 gene and the presence of the MDR1 gene are associated with many malignant tumors including endometrial cancer and are responsible for cancer therapeutic resistance and poor survival. Thus, there is a critical need to devise novel combinatorial therapies with multiple mechanisms of action to overcome drug resistance. Here, we report a new ciprofloxacin derivative (CIP2b) tested either alone or in combination with taxanes against four human endometrial cancer cell lines. In vitro studies revealed that a combination of paclitaxel + CIP2b had synergistic cytotoxic effects against MDR1-expressing type-II human endometrial cancer cells with loss-of-function p53 (Hec50co LOFp53). Enhanced antitumor effects were confirmed by substantial increases in caspase-3 expression, cell population shifts toward the G2/M phase, and reduction of cdc2 phosphorylation. It was found that CIP2b targets multiple pathways including the inhibition of MDR1, topoisomerase I, and topoisomerase II, as well as enhancing the effects of paclitaxel (PTX) on microtubule assembly. In vivo treatment with the combination of PTX + CIP2b also led to significantly increased accumulation of PTX in tumors (compared to CIP2b alone) and reduction in tumor growth. Enhanced in vivo cytotoxic effects were confirmed by histological and immunohistochemical examination of the tumor tissues. Complete blood count and blood biochemistry data confirmed the absence of any apparent off-target toxicity. Thus, combination therapy involving PTX and CIP2b targeted multiple pathways and represents an approach that could result in improved tolerance and efficacy in patients with type-II endometrial cancer harboring the MDR1 gene and p53 mutations.

A systematic literature review of the epidemiology, quality of life, and economic burden, including disease pathways and treatment patterns of relapsed/refractory classical Hodgkin lymphoma

INTRODUCTION

A systematic literature review was conducted to understand disease burden in patients with relapsed/refractory classical Hodgkin lymphoma (R/R cHL).

AREAS COVERED

Embase®, PubMed®, and Cochrane were searched for records from 2001 to 2020 in accordance with PRISMA guidelines. A total of 13,257 abstracts and 1731 papers were screened; 144 studies were identified. cHL accounted for 0.5% of all cancers, with 4‒66.7% of cases progressing to R/R disease (studies with >500 patients); this range varied across countries. Quality of life (QoL) was assessed via EORTC-QLQ-C30 (n = 7), EQ-5D (n = 5), SF-36 (n = 3), FACIT-F (n = 1), and MFI (n = 1) questionnaires. In general, pembrolizumab and other programmed cell death protein-1 inhibitors improved QoL scores. Brentuximab vedotin showed mixed outcomes, and high-dose therapy (HDT) and autologous stem-cell rescue (ASCR) showed worsening functionality/symptoms. Economic burden studies (n = 21) reported increased costs and health care resource in R/R cHL. Across clinical guidelines (n = 13) and treatment pattern studies (n = 46), HDT followed by ASCR was recommended as initial R/R cHL treatment. Pembrolizumab and nivolumab were frequently recommended for patients relapsing following HDT/ASCR.

EXPERT OPINION

Despite recent treatment advances, patients with R/R cHL continue to report reduced quality of life. Unmet medical needs remain, particularly with respect to slowing disease progression and identifying the best treatment approaches for improving longer-term survival and quality of life. This systematic literature review provides an extensive overview of the current landscape in patients with R/R cHL, focusing on four key areas: epidemiology, QoL, economic burden, and disease management. These findings will be useful to those with an interest in managing patients with R/R cHL or in designing future studies.

PD-1/PD-L1 Pathway: A Therapeutic Target in CD30+ Large Cell Lymphomas

The programmed death-ligands, PD-L1 and PD-L2, reside on tumor cells and can bind with programmed death-1 protein (PD-1) on T-cells, resulting in tumor immune escape. PD-1 ligands are highly expressed in some CD30+ large cell lymphomas, including classic Hodgkin lymphoma (CHL), primary mediastinal large B-cell lymphoma (PMBL), Epstein–Barr virus (EBV)-positive diffuse large B-cell lymphoma (EBV+ DLBCL), and anaplastic large cell lymphoma (ALCL). The genetic alteration of the chromosome 9p24.1 locus, the location of PD-L1, PD-L2, and JAK2 are the main mechanisms leading to PD-L1 and PD-L2 overexpression and are frequently observed in these CD30+ large cell lymphomas. The JAK/STAT pathway is also commonly constitutively activated in these lymphomas, further contributing to the upregulated expression of PD-L1 and PD-L2. Other mechanisms underlying the overexpression of PD-L1 and PD-L2 in some cases include EBV infection and the activation of the mitogen-activated protein kinase (MAPK) pathway. These cellular and molecular mechanisms provide a scientific rationale for PD-1/PD-L1 blockade in treating patients with relapsed/refractory (R/R) disease and, possibly, in newly diagnosed patients. Given the high efficacy of PD-1 inhibitors in patients with R/R CHL and PMBL, these agents have become a standard treatment in these patient subgroups. Preliminary studies of PD-1 inhibitors in patients with R/R EBV+ DLBCL and R/R ALCL have also shown promising results. Future directions for these patients will likely include PD-1/PD-L1 blockade in combination with other therapeutic agents, such as brentuximab or traditional chemotherapy regimens.

Autologous stem cell transplantation after anti-PD-1 therapy for multiply relapsed or refractory Hodgkin lymphoma

Autologous stem cell transplantation (ASCT) can be curative for patients with relapsed/refractory Hodgkin lymphoma (HL). Based on studies suggesting that anti-PD-1 monoclonal antibodies (mAbs) can sensitize patients to subsequent chemotherapy, we hypothesized that anti-PD-1 therapy before ASCT would result in acceptable outcomes among high-risk patients who progressed on or responded insufficiently to ≥1 salvage regimen, including chemorefractory patients who are traditionally considered poor ASCT candidates. We retrospectively identified 78 HL patients who underwent ASCT after receiving an anti-PD-1 mAb (alone or in combination) as third-line or later therapy across 22 centers. Chemorefractory disease was common, including 42 patients (54%) refractory to ≥2 consecutive systemic therapies immediately before anti-PD-1 treatment. Fifty-eight (74%) patients underwent ASCT after anti-PD-1 treatment, while 20 patients (26%) received additional therapy after PD-1 blockade and before ASCT. Patients received a median of 4 systemic therapies (range, 3-7) before ASCT, and 31 patients (41%) had a positive pre-ASCT positron emission tomography (PET) result. After a median post-ASCT follow-up of 19.6 months, the 18-month progression-free survival (PFS) and overall survival were 81% (95% CI, 69-89) and 96% (95% confidence interval [CI], 87-99), respectively. Favorable outcomes were observed for patients who were refractory to 2 consecutive therapies immediately before PD-1 blockade (18-month PFS, 78%), had a positive pre-ASCT PET (18-month PFS, 75%), or received ≥4 systemic therapies before ASCT (18-month PFS, 73%), while PD-1 nonresponders had inferior outcomes (18-month PFS, 51%). In this high-risk cohort, ASCT after anti-PD-1 therapy was associated with excellent outcomes, even among heavily pretreated, previously chemorefractory patients.

FDG PET for Assessment of Autologous Stem Cell Transplantation

The appropriate selection of patients to undergo hematopoietic stem cell transplant (HSCT) is critical due to the risk of treatment-related morbidity and mortality. The prognostic value of FDG-PET/CT in response assessment in hematologic malignancies is well-established and has led to numerous investigations into the role of FDG-PET/CT in the evaluation of patients in the setting of HSCT. This article discusses the most common indications for autologous stem cell transplant (autoSCT) in which FDG-PET/CT has been evaluated, including for lymphoma and multiple myeloma. For relapsed/refractory Hodgkin lymphoma, achieving a negative FDG-PET/CT scan, regardless of the number of the regimens, prior to autoSCT is an important prognostic factor for posttransplant outcome. The data in the pretransplant setting are more variable for non-Hodgkin lymphoma. For both Hodgkin and non-Hodgkin lymphoma, studies have primarily used a visual assessment for FDG-PET/CT interpretation, with the Deauville score the current standard criteria. Optimization of thresholds for specific regimens pretransplant as well as integration of additional semiquantitative parameters to assess response remain active areas of research. For multiple myeloma, FDG-PET/CT has emerged as the recommended imaging modality of choice for assessing response to treatment. Data suggest that FDG-PET/CT may provide prognostic and predictive value for assessing outcome after autoSCT.

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.

The comparison of effectiveness and safety between different biosimilars of G-CSF in the mobilization of peripheral blood stem cells (PBSCs) for autologous transplantation (autologous peripheral blood stem cell transplantation, auto-PBSCT)

BACKGROUND

Autologous peripheral blood marrow stem cell transplantation (auto-PBSCT) preceded by high-dose chemotherapy is a well-known method of treatment for patients with hematological cancers. Performing the procedure entails obtaining from the patient their own stem cells from peripheral blood using G-CSF. Currently, various filgrastim biosimilars are widely used.

AIM OF THE STUDY

The purpose of this study is to compare the efficacy and safety of three different biosimilars of filgrastim in PBSC mobilization in patients with hematological malignancies.

MATERIALS AND METHODS

This is a retrospective analysis of 282 patients (118 women and 164 men) who underwent stem cells mobilization for auto-PBSCT in the Department of Hematology in Wroclaw in 2012-2014. Three filgrastim biosimilars were used: Tevagrastim (95), Nivestim (92), and Zarzio (95). Ninety patients (32%) were diagnosed with multiple myeloma, 55 (19%) with Hodgkin's lymphoma, 90 (32%) with NHLs, 20 (7%) with acute myeloid leukemia, and 27 (10%) with another hematological cancer.

RESULTS

The mean number of CD34+ cells collected during the first leukapheresis was 5.95 × 10⁶ /kg for Tevagrastim, 7.08 × 10⁶ /kg for Nivestim, and 6.8 × 10⁶ /kg for Zarzio (P > .05). The necessary number of leukapheresis for patients receiving Zarzio, Nivestim, and Tevagrastim was 1.32, 1.37, and 1.66, respectively (P > .05). The percentage of effective mobilizations was 88.2% for Zarzio, 86.2% for Nivestim, and 84.9% for Tevagrastim. The side effects included bone pain and headache.

CONCLUSION

All tested biosimilars demonstrated similar effectiveness and safety profiles in patients with hematological tumors undergoing PBSC mobilization; therefore, they can be used interchangeably.

Novel Biomarker Approaches in Classic Hodgkin Lymphoma

Classic Hodgkin lymphoma (cHL) is one of the most common lymphomas in the Western world. Advances in the management of cHL have led to high cure rates exceeding 80%. Nevertheless, relapse or refractory disease in a subset of patients and treatment-related toxicity still represents unsolved clinical problems. The introduction of targeted treatments such as PD-1 blockade and the CD30 antibody drug conjugate, brentuximab vedotin, has broadened treatment options in cHL, emphasizing the critical need to identify biomarkers with the goal to provide rationales for treatment selection, increase effective drug utilization, and minimize toxicity. The unique biology of cHL featuring low abundant tumor cells and numerous nonmalignant immune cells in the tumor microenvironment can provide various types of promising biomarkers related to the tumor cells directly, tumor microenvironment cross-talk, and host immune response. Here, we comprehensively review novel biomarkers including circulating tumor DNA and gene expression-based prognostic models that might guide the ideal management of cHL in the future.

Small Centers with Big Ventures: Autologous Stem Cell Transplantation Survival Data

We present the first-ever autologous stem cell transplantation (ASCT) outcome data from a secondary-care healthcare facility. Albeit exact details of patient and disease characteristics and co-morbidity scores for all patients are not available, the engraftment and survival data is very similar to those published from large tertiary-care cancer centres, both regionally and internationally. Transplant Related Mortality (TRM) of 3.1% is within the expected range and includes a patient who died of acute drug reaction (ADR) during conditioning chemotherapy, prior to the ASCT. Furthermore, cyclophosphamide mobilization chemotherapy is given in the outpatient setting. This study is important in terms of healthcare resource optimization as well as patients’ convenience and highlights that ASCT can be performed in a safe and effective manner with comparable survival rates even at a DGH, provided the centre stays abreast with the recent developments and can offer its patients with standard of care treatment of the era.

Cost-effectiveness of brentuximab vedotin plus chemotherapy as frontline treatment of stage III or IV classical Hodgkin lymphoma

OBJECTIVE

The ECHELON-1 trial demonstrated efficacy and safety of brentuximab vedotin plus doxorubicin, vinblastine, and dacarbazine (A + AVD) vs doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) as frontline therapy for stage III/IV classical Hodgkin lymphoma. This analysis evaluated the cost-effectiveness of A + AVD from a US healthcare payer perspective.

METHODS

The incremental cost-effectiveness ratio (ICER), defined as the incremental costs per quality-adjusted life year (QALY) gained, was estimated using a non-homogenous semi-Markov cohort model with health states defined on progression following frontline treatment, and for those with progression, receipt of autologous stem-cell transplant (ASCT), and progression after ASCT. Patients undergoing ASCT were classified as refractory or relapsed based on timing of progression. Probabilities of progression/death with frontline therapy were based on parametric survival distributions fit to data on modified progression-free survival (mPFS) from ECHELON-1. Duration of frontline treatment and incidence of adverse events were from ECHELON-1. Utility values for patients in the frontline mPFS state were based on EQ-5D data from ECHELON-1. Other inputs were from published sources. A lifetime time horizon was used. Costs and QALYs were discounted at 3%. Analyses were conducted alternately using data on mPFS for the overall and North American populations of ECHELON-1.

RESULTS

The ICER for A + AVD vs ABVD was $172,074/QALY gained in the analysis using data on mPFS for the overall population and $69,442/QALY gained in the analysis using data on mPFS for the North American population of ECHELON-1. The ICER is sensitive to estimated costs of ASCT and frontline failure.

CONCLUSION

The ICER for A + AVD vs ABVD based on ECHELON-1 is within the range of threshold values for cost-effectiveness in the US. A + AVD is, therefore, likely to be a cost-effective frontline therapy for patients with stage III/IV classical Hodgkin lymphoma from a US healthcare payer perspective.

Cost-effectiveness of pembrolizumab versus brentuximab vedotin for patients with relapsed or refractory classical Hodgkin's lymphoma: a United States payer perspective

AIMS

Patients with classical Hodgkin's lymphoma (cHL) who have relapsed after or are ineligible for autologous stem cell transplantation (ASCT) have limited treatment options and generally a poor prognosis. Pembrolizumab was recently approved in the US for the treatment of such patients having demonstrated clinical benefit and tolerability in relapsed/refractory cHL; however, the cost-effectiveness of pembrolizumab in this population is currently unknown.

MATERIALS AND METHODS

A three-state Markov model (progression-free [PF], progressed disease, and death) was developed to assess the cost-effectiveness of pembrolizumab (200 mg) vs brentuximab vedotin (BV; 1.8 mg/kg) in patients with relapsed/refractory cHL after ASCT who have not received BV post-ASCT over a 20-year time horizon from a US payer perspective. PF survival was modeled using a naïve indirect treatment comparison of data from KEYNOTE-087 and the SG035-003 trial. Post-progression survival was modeled using data from published literature. Costs (drug acquisition and administration, disease management, subsequent treatment, and adverse events) and outcomes were discounted at an annual rate of 3.0%. Uncertainty surrounding cost-effectiveness was assessed via probabilistic, deterministic, and scenario analyses.

RESULTS

In the base case, pembrolizumab was predicted to yield an additional 0.574 life-years (LYs) and 0.500 quality-adjusted life-years (QALYs) vs BV and cost savings of $63,278. Drug acquisition costs were the biggest driver of incremental costs between strategies. Pembrolizumab had a 99.6% probability of being cost-effective compared with BV at a willingness-to-pay threshold of $20,000/QALY and dominated BV in all scenarios tested.

LIMITATIONS

The analysis was subject to potential bias due to the use of a naïve indirect treatment comparison and, given the current immaturity of OS in KEYNOTE-087, PPS was assumed equivalent across both treatments.

CONCLUSION

Pembrolizumab is a cost-effective alternative to BV for patients with relapsed/refractory cHL after ASCT.

Sequential immunotherapy in a patient with primary refractory Hodgkin lymphoma and novel mutations

Primary resistant Hodgkin lymphoma is an aggressive disease with few treatment options and short survival. Neoplastic cells of classical Hodgkin lymphoma are heavily dependent on microenvironmental stimuli, regularly express PD-L1, and a relevant proportion of relapsed patients is sensitive to blocking of the PD1/PD-L1 axis. However, response duration is limited and further treatment options are unknown but urgently needed.

We report a case of a patient without relevant response to five subsequent chemotherapy regimens who immediately and dramatically responded to an anti-PD1 mab. During the following two years she responded to the anti-CTLA-4 mab ipilimumab, the Jak2 inhibitor ruxolitinib, and a combination of lenalidomide plus cyclophosphamide given in subsequent relapses. A thorough genomic analysis demonstrated seven genomic alterations with six of them not previously described in this disease (i.e. BRIP1 G212fs*62, KRAS L19F, KDM5A R1239W, MYC A59T, ARIDA1A E1683fs*15 and TP53 277Y). Three alterations were considered actionable and one of them drugable. The number of mutations increased over time and the BRIP1 mutation was found to be a germline mutation.

Pembrolizumab and its role in relapsed/refractory classical Hodgkin's lymphoma: evidence to date and clinical utility

Immune evasion is a critical mechanism of malignant cell survival, and relies in part on molecular signaling through the programmed cell death 1 (PD-1)/PD-1 ligand (PD-L1) axis that contributes to T cell exhaustion. Immune modulatory therapy with monoclonal antibodies against PD-1 designed to enhance antitumor immune response have shown promise in the treatment of advanced solid tumors and hematologic malignancies. Classical Hodgkin's lymphoma (cHL), a unique B cell malignancy characterized by an extensive but ineffective immune cell infiltrate surrounding a small number of tumor cells, has shown significant response to anti-PD-1 directed therapy. The anti-PD-1 monoclonal antibodies nivolumab and pembrolizumab have shown similarly remarkable activity in relapsed/refractory cHL and have been approved by the Food and Drug Administration for treatment of this disease. In this article we review the rationale of targeting the PD-1/PD-L1 axis in cHL and the pharmacology of pembrolizumab, and summarize the data on activity and safety profile of this agent in the treatment of relapsed/refractory cHL. We also discuss the potential benefits and pitfalls of using PD-1 blockade in the setting of allogeneic stem-cell transplantation, and summarize ongoing prospective trials of single-agent pembrolizumab and combination strategies as well as future directions.

PD-1 /PD-L1 checkpoint in hematological malignancies

Programmed cell death protein 1 (PD-1), is a cell surface receptor with an important role in down-regulating the immune system and promoting self-tolerance by suppressing T cell inflammatory activity. PD-1/PDL1 axis represents a checkpoint to control immune responses and it is often used as a mechanism of immune escaping by cancers and infectious diseases. Many data demonstrate its important role in solid tumors and report emerging evidences in lymphoproliferative disorders. In this review, we summarized the available data on the role of PD-1/PD-L1 checkpoint in lymphoproliferative diseases and the therapeutics use of monoclonal blocking antibodies.

Prognostic Model to Predict Post-Autologous Stem-Cell Transplantation Outcomes in Classical Hodgkin Lymphoma

Purpose Our aim was to capture the biology of classical Hodgkin lymphoma (cHL) at the time of relapse and discover novel and robust biomarkers that predict outcomes after autologous stem-cell transplantation (ASCT). Materials and Methods We performed digital gene expression profiling on a cohort of 245 formalin-fixed, paraffin-embedded tumor specimens from 174 patients with cHL, including 71 with biopsies taken at both primary diagnosis and relapse, to investigate temporal gene expression differences and associations with post-ASCT outcomes. Relapse biopsies from a training cohort of 65 patients were used to build a gene expression-based prognostic model of post-ASCT outcomes (RHL30), and two independent cohorts were used for validation. Results Gene expression profiling revealed that 24% of patients exhibited poorly correlated expression patterns between their biopsies taken at initial diagnosis and relapse, indicating biologic divergence. Comparative analysis of the prognostic power of gene expression measurements in primary versus relapse specimens demonstrated that the biology captured at the time of relapse contained superior properties for post-ASCT outcome prediction. We developed RHL30, using relapse specimens, which identified a subset of high-risk patients with inferior post-ASCT outcomes in two independent external validation cohorts. The prognostic power of RHL30 was independent of reported clinical prognostic markers (both at initial diagnosis and at relapse) and microenvironmental components as assessed by immunohistochemistry. Conclusion We have developed and validated a novel clinically applicable prognostic assay that at the time of first relapse identifies patients with unfavorable post-ASCT outcomes. Moving forward, it will be critical to evaluate the clinical use of RHL30 in the context of positron emission tomography-guided response assessment and the evolving cHL treatment landscape.

Risk-adapted transplant strategies for high-risk Hodgkin lymphoma: are we there?

PURPOSE OF REVIEW

The treatment of high-risk classic Hodgkin lymphoma (cHL) patients remains challenging, especially after autologous stem cell transplant (ASCT) failure. Moreover, the outcome of chemorefractory patients is still poor.

RECENT FINDINGS

The development of novel targeted therapies has changed the therapeutic options for high-risk patients. To improve outcome, treatment algorithms should integrate up-front, newly established prognostic markers. Tandem ASCT instead of single ASCT has been proposed as an option to improve outcome for high-risk patients. Availability of less toxic reduced intensity conditioning regimens and recent development in haploidentical transplantation have widened applicability and improved outcomes of allo-hematopoietic cell transplantation. Their exact role in cHL is still controversial and there is no consensus on the optimal transplantation strategy. In this context, results of tandem ASCT should also be compared with those of the autologous/reduced intensity conditioning-allo tandem approach. In this review, we discuss how transplantation strategies (auto and allo) can fit into the salvage treatment plan for patients with relapsed/refractory cHL, taking into account the new drugs available and integrating modern risk assessment.

SUMMARY

We speculated that improvements could be achieved by transplanting patients in earlier phases of their disease, if necessary after 'bridging' using the new drugs, and we propose an algorithm integrating the different treatment options.

Emerging treatment options for the management of Hodgkin's lymphoma: clinical utility of nivolumab

Classical Hodgkin's lymphoma (cHL) is a B-cell malignancy comprised of pathologic Reed Sternberg cells with a surrounding immune-tolerant inflammatory milieu. RS cells evade immune recognition in part through programmed death ligand 1 (PD-L1) overexpression, which is genetically programmed through copy number alterations, polysomy, and amplification of the 9p24.1 locus encoding PD-L1. By engaging with PD-1+ T-cells, PD-L1 delivers a potent immune suppressive signal promoting immunologic escape of the tumor cell. Enhancing antitumor immune response by targeting PD-1 with the monoclonal antibody nivolumab has proved to be effective in multiple solid tumors, but the highest response rates to date have been reported in patients with cHL, with over 65% of treated patients achieving an objective clinical response. In this review, we will summarize the published evidence regarding the activity of nivolumab in cHL as well as its current place in therapy. We will review the pharmacology, mechanism of action, and side effects of nivolumab as well as the emerging data indicating possible increased risk of graft versus host disease in patients treated with PD-1 inhibitors either pre- or post-allogeneic stem cell transplant. Given the remarkable single-agent activity and safety profile of PD-1 inhibitors in heavily pretreated patients with cHL, the possibility of employing nivolumab in combination with other active agents and earlier in therapy is a promising area of active investigation, and we will briefly summarize current clinical trials.

Hodgkin’s Lymphoma - evaluation of patients submitted to Autologous transplantation of hematopoietic cells in the Hematology Service of the Hospital Walter Cantídio – Fortaleza, Brazil

SUMMARY The Autologous HSCT is an important alternative for refractory or recurrent HL patients in terms of survival and improved quality of life. This study analyzes the results of autologous BMT performed in HL patients in the Transplant Unit of the HUWC/ HEMOCE (Fortaleza - CE, Brazil). Fifty-two transplanted patients were studied from January 2009 to October 2015, among them, 30 men and 22 women, mean age of 28.2 years. All of them received GCS-F during the mobilization, in some cases associated with Vinorelbine or Plerixafor, with CD34 collection averaging 4.8 CD34/kg. The conditioning was performed with BEAC, NEAM or BEAM and the grafting with an average of 10 days. The evaluation on D + 100 showed: CR - 42 (82.7%), PR - 08 (13.5%) and 02 (3.8%) deaths, three and six days after cell infusion. After the D+100, 08 patients in CR showed HL recurrence from 06 to 36 months; 03 died and 05 are being treated with brentuximab; among the 08 patients in PR, 01 died due to HL activity, 04 months after BMT and 07 patients are undergoing treatment. The final evaluation of HL transplant patients showed an OS of 88.5% and a DFS of 61.5% in 6 years, with OS of the chemosensitive patients of 81% and of the chemoresistant ones, of 72.6%. It is possible to conclude that the Autologous HSCT has shown to be an excellent rescue therapy regarding tolerance, as well as the overall survival.

Pembrolizumab in classical Hodgkin's lymphoma

Pembrolizumab is a humanized monoclonal antibody directed against programmed cell death protein 1 (PD-1), a key immune-inhibitory molecule expressed on T cells and implicated in CD4+ T-cell exhaustion and tumor immune-escape mechanisms. Classical Hodgkin's lymphoma (cHL) is a unique B-cell malignancy in the sense that malignant Reed-Sternberg (RS) cells represent a small percentage of cells within an extensive immune cell infiltrate. PD-1 ligands are upregulated on RS cells as a consequence of both chromosome 9p24.1 amplification and Epstein-Barr virus infection and by interacting with PD-1 promote an immune-suppressive effect. By augmenting antitumor immune response, pembrolizumab and nivolumab, another monoclonal antibody against PD-1, have shown significant activity in patients with relapsed/refractory cHL as well as an acceptable toxicity profile with immune-related adverse events that are generally manageable. In this review, we explore the rationale for targeting PD-1 in cHL, review the clinical trial results supporting the use of checkpoint inhibitors in this disease, and present future directions for investigation in which this approach may be used.

Species differences in tumour responses to cancer chemotherapy

Despite advances in chemotherapy, radiotherapy and targeted drug development, cancer remains a disease of high morbidity and mortality. The treatment of human cancer patients with chemotherapy has become commonplace and accepted over the past 100 years. In recent years, and with a similar incidence of cancer to people, the use of cancer chemotherapy drugs in veterinary patients such as the dog has also become accepted clinical practice. The poor predictability of tumour responses to cancer chemotherapy drugs in rodent models means that the standard drug development pathway is costly, both in terms of money and time, leading to many drugs failing in Phase I and II clinical trials. This has led to the suggestion that naturally occurring cancers in pet dogs may offer an alternative model system to inform rational drug development in human oncology. In this review, we will explore the species variation in tumour responses to conventional chemotherapy and highlight our understanding of the differences in pharmacodynamics, pharmacokinetics and pharmacogenomics between humans and dogs. Finally, we explore the potential hurdles that need to be overcome to gain the greatest value from comparative oncology studies.

Improved outcome of patients with relapsed/refractory Hodgkin lymphoma with a new fotemustine-based high-dose chemotherapy regimen

High-dose chemotherapy (HDT) with autologous stem cell transplantation is the standard of care for relapsed/refractory (RR) Hodgkin lymphoma (HL). Given that HDT may cure a sizeable proportion of patients refractory to first salvage, development of newer conditioning regimens remains a priority. We present the results of a novel HDT regimen in which carmustine was substituted by a third-generation chloroethylnitrosourea, fotemustine, with improved pharmacokinetics and safety (FEAM; fotemustine, etoposide, cytarabine, melphalan) in 122 patients with RR-HL accrued into a prospective registry-based study. Application of FEAM resulted in a 2-year progression-free survival (PFS) of 73·8% [95% confidence interval (CI), 0·64-0·81] with median PFS, overall survival and time to progression yet to be reached. The 2-year risk of progression adjusted for the competitive risk of death was 19·4% (95% CI, 0·12-0·27) for the entire patient population. Most previously established independent risk factors, except for fluorodeoxyglucose ((18) (F) FDG)-uptake, were unable to predict for disease progression and survival after FEAM. Although 32% of patients had (18) (F) FDG-positrin emission tomography-positive lesions before HDT, the 2-year risk of progression adjusted for competitive risk of death was 19·4% (95% CI; 0·12-0·27). No unusual acute toxicities or early/late pulmonary adverse events were registered. FEAM emerges as an ideal HDT regimen for RR-HL patients typically pre-exposed to lung-damaging treatments.

How I treat relapsed classical Hodgkin lymphoma after autologous stem cell transplant

Despite the success of standard front-line chemotherapy for classical Hodgkin lymphoma (cHL), a subset of these patients, particularly those with poor prognostic factors at diagnosis (including the presence of B symptoms, bulky disease, advanced stage, or extranodal disease), relapse. For those patients who relapse following autologous stem cell transplant (SCT), multiple treatment options are available, including single-agent chemotherapy, combination chemotherapy strategies, radiotherapy, the immunoconjugate brentuximab, checkpoint inhibitors nivolumab and pembrolizumab, lenalidomide, everolimus, or observation in selected patients. In patients with an available donor, allogeneic SCT may also be considered. With numerous treatment options available, we advocate for a tailored therapeutic approach for patients with relapsed cHL guided by patient-specific characteristics including age, comorbidities, sites of disease (nodal or organ), previous chemosensitivity, and goals of treatment (long-term disease control vs allogeneic SCT).