Clinical outcomes of relapsed and refractory Hodgkin lymphoma patients after contemporary first-line treatment: a German Hodgkin Study Group analysis

Circulating Tumor DNA Sequencing for Biologic Classification and Individualized Risk Stratification in Patients With Hodgkin Lymphoma

PURPOSE

Current clinical challenges in Hodgkin lymphoma (HL) include difficult-to-treat relapsed/refractory disease and considerable long-term toxicities of treatment. Since clinical risk factors lack discriminatory power, intensity of therapy is mainly based on tumor burden. Exploring HL genetics and tumor microenvironment (TME) might provide valuable insights for improved risk stratification.

MATERIALS AND METHODS

In this study, we applied circulating tumor DNA sequencing to 243 patients obtained from pivotal German Hodgkin Study Group trials to identify subtypes of HL. Independent validation of the subtypes was performed in 96 patients treated in the EuroNet-PHL-C2 study. Outcome differences of subtypes were assessed in an event-enriched clinical validation cohort comprising 72 patients from the HD21 trial, using a refined, validated, and clinically feasible assay.

RESULTS

We propose a biologic classification of HL consisting of three distinct subtypes: inflammatory immune escape HL is characterized by frequent copy-number variations including immune escape variants such as high-level amplifications of the PD-L1 locus and an inflammatory TME. Virally-driven HL is associated with Epstein-Barr virus and/or human herpesvirus 6 and an inflammatory TME with neutrophils and macrophages, while the tumor mutational burden (TMB) is low. Oncogene-driven HL is defined by a high TMB, recurrent mutations in oncogenic drivers such as TNFAIP3, ITPKB, and SOCS1, and a cold TME. A refined and validated assay version aiming at clinically feasible risk stratification showed significant progression-free survival differences between subtypes. In addition, assessment of minimal residual disease (MRD) allowed for the detection of patients at very high risk of relapse within the subtypes.

CONCLUSION

We propose a clinically feasible, noninvasive method for individualized risk stratification and MRD monitoring in patients with HL on the basis of circulating tumor DNA sequencing.

Proceedings from the First Onco Summit: LATAM Chapter, 19-20 May 2023, Rio de Janeiro, Brazil

The Onco Summit 2023: The Latin American (LATAM) Chapter took place over two days, from 19-20 May 2023, in Brazil. The event aimed to share the latest updates across various oncology disciplines, address critical clinical challenges, and exchange best practices to ensure optimal patient treatment. More than 30 international and regional speakers and more than 300 oncology specialists participated in the Summit. The Summit discussions centered on common challenges and therapeutic advances in cancer care, with a specific focus on the unique obstacles faced in LATAM and examples of adaptable strategies to address these challenges. The Summit also facilitated the establishment of a network of oncologists, hematologists, and scientists in LATAM, enabling collaboration to improve cancer care, both in this region and globally, through drug development and clinical research. This report summarizes the key discussions from the Summit for the global and LATAM oncology community.

Treatment approaches for older Hodgkin lymphoma patients

PURPOSE OF REVIEW

Hodgkin lymphoma (HL) occurs at two age peaks around 25 and 60 years of age. Due to varying fitness and co-morbidities older patients are a heterogeneous group that has relatively poor treatment outcomes. The evolving therapeutic landscape for older HL is summarized herein.

RECENT FINDINGS

Due to lack of data from larger trials and approval of novel drugs, first-line treatment of limited-stage HL (i.e. early-stage favourable and unfavourable) remains largely A(B)VD and radiotherapy based. For patients with advanced-stage HL, the anti-CD30 antibody-drug conjugate brentuximab vedotin is approved in combination with AVD chemotherapy (BV-AVD). Due to toxicities such as febrile neutropenia or polyneuropathy and lack of improvement in progression-free and overall survival in the older subgroup, fully concomitant BV-AVD is however not used widely. More recently, promising early data was reported with the combination of nivolumab and AVD (N-AVD) in patients >60 years with advanced-stage HL. Second-line treatment depends on fitness and might include high-dose chemotherapy and autologous stem-cell transplantation for selected patients. For unfit or multiply relapsed patients, anti-PD1 antibodies are the preferred treatment option.

SUMMARY

The increasing number of older HL patients constitutes a therapeutic challenge despite recent advances and the increased usage of targeted agents.

Optimizing salvage therapy for Hodgkin lymphoma: progress and future challenges

INTRODUCTION

Despite clear advancements in the management of classical Hodgkin lymphoma (cHL) over the past decade including better risk stratification, the usage of 18F-flurodeoxyglucose positron emission tomography (FDG-PET)-guided approaches and incorporation of novel agents, approximately one-third of the patients will relapse. Important themes have been recently explored in the first salvage setting including the recognition of the positive prognostic value of a negative pre-autologous stem cell transplantation (ASCT) FDG-PET response and the incorporation of novel agents such as brentuximab vedotin (BV) and immune checkpoint inhibitors (CPIs) as salvage regimens to improve patient outcomes.

AREAS COVERED

The evolving treatment paradigm in optimizing salvage therapy in relapsed refractory cHL (RR-cHL) is discussed, including a vision to the future. The methodology included a literature search on PubMed using keywords. Selected articles were screened and evaluated by the authors of this review.

EXPERT OPINION

Achieving a complete remission by FDG-PET pre-ASCT is the most important prognostic factor in obtaining disease control and subsequent cure, and therefore should be a key goal of any salvage regimen. Although data from randomized controlled trials are currently lacking, retrospective evidence demonstrate superior event free survival with CPI-based regimens compared to conventional chemotherapy or BV-based therapy.

Brentuximab vedotin and chemotherapy in relapsed/refractory Hodgkin lymphoma: a propensity score-matched analysis

ABSTRACT

Several single-arm studies have explored the inclusion of brentuximab vedotin (BV) in salvage chemotherapy followed by autologous stem cell transplantation (ASCT) for relapsed/refractory (R/R) classical Hodgkin lymphoma (cHL). However, no head-to-head comparisons with standard salvage chemotherapy have been performed. This study presents a propensity score-matched analysis encompassing individual patient data from 10 clinical trials to evaluate the impact of BV in transplant-eligible patients with R/R cHL. We included 768 patients, of whom 386 were treated with BV with or without chemotherapy (BV cohort), whereas 382 received chemotherapy alone (chemotherapy cohort). Propensity score matching resulted in balanced cohorts of 240 patients each. No significant differences were observed in pre-ASCT complete metabolic response (CMR) rates (P = .69) or progression free survival (PFS; P = .14) between the BV and chemotherapy cohorts. However, in the BV vs chemotherapy cohort, patients with relapsed disease had a significantly better 3-year PFS of 80% vs 70%, respectively (P = .02), whereas there was no difference for patients with primary refractory disease (56% vs 62%, respectively; P = .67). Patients with stage IV disease achieved a significantly better 3-year PFS in the BV cohort (P = .015). Post-ASCT PFS was comparable for patients achieving a CMR after BV monotherapy and those receiving BV followed by sequential chemotherapy (P = .24). Although 3-year overall survival was higher in the BV cohort (92% vs 80%, respectively; P < .001), this is likely attributed to the use of other novel therapies in later lines for patients experiencing progression, given that studies in the BV cohort were conducted more recently. In conclusion, BV with or without salvage chemotherapy appears to enhance PFS in patients with relapsed disease but not in those with primary refractory cHL.

Adipose tissue indices predict prognosis in hodgkin lymphoma

INTRODUCTION BACKGROUND

This study evaluated the impact of adipose tissue indices on prognosis of HL.

METHODS

Fifty-five patients with newly diagnosed Hodgkin Lymphoma were evaluated retrospectively for association with adipose tissue indices (total abdominal tissue volume, radiodensity, subcutaneous and visceral adipose tissue SUVmax value and prognostic factors for Hodgkin Lymphoma such as IPS-3, IPS-7, stage, sedimentation, progression free and overall survival.

RESULTS

For IPS-3, SAT SUVmax and TAAT radiodensity were significantly increased in high-risk patients (2and 3) compared to group 0 and 1. For IPS-7, total abdominal adipose volume was significantly decreased in high-risk patients, SAT SUVmax significantly increased in high-risk patients and decreased in low-risk patients. In addition, SAT SUVmax was significantly increased in patients with high sedimentation rate, with B symptoms and who passed away during follow-up. SAT SUVmax showed moderate positive correlation with sedimentation, IPS-3, IPS-7, and stage. In addition, it was observed that TAAT radiodensity and SAT SUVmax were significantly better for determining prognosis than other adipose tissue indices. Roc analysis showed that the diagnostic value of all adipose tissue indices in predicting IPS-3 and IPS-7 prognoses were statistically significant.

CONCLUSION

SAT SUVmax and TAAT radiodensity were two new and independent markers with diagnostic value in predicting prognosis.

BET inhibitors induce NF-κB and E2F downregulation in Hodgkin and Reed-Sternberg cells

The prognosis of patients with relapsed and/or refractory classic Hodgkin lymphoma (cHL) continues to be poor. Therefore, there is a continuing need to develop novel therapies and to rationalize the use of target combinations. In recent years there has been growing interest in epigenetic targets for hematological malignancies under the rationale of the presence of common alterations in epigenetic transcriptional regulation. Since Hodgkin and Reed-Sternberg (HRS) cells have frequent inactivating mutations of the CREBBP and EP300 acetyltransferases, bromodomain and extra-terminal (BET) inhibitors can be a rational therapy for cHL. Here we aimed to confirm the efficacy of BET inhibitors (iBETs) using representative cell models and functional experiments, and to further explore biological mechanisms under iBET treatment using whole-transcriptome analyses. Our results reveal cytostatic rather than cytotoxic activity through the induction of G1/S and G2/M cell-cycle arrest, in addition to variable MYC downregulation. Additionally, massive changes in the transcriptome induced by the treatment include downregulation of relevant pathways in cHL disease: NF-kB and E2F, among others. Our findings support the therapeutic use of iBETs in selected cHL patients and reveal previously unknown biological mechanisms and consequences of pan-BET inhibition.

The role of transplantation in Hodgkin lymphoma

Despite the success of frontline anthracycline-based chemotherapy for classical Hodgkin Lymphoma (cHL), approximately 15% of patients do not achieve an adequate response and require further therapy. For transplant-eligible patients, additional treatment followed by high-dose chemotherapy and autologous hematopoietic stem cell transplantation (autoHCT) provides a durable response in 50% of patients. The most refractory patients, including those requiring multiple lines of therapy to achieve a response or those relapsing after an autoHCT, may achieve long-term survival with allogeneic hematopoietic stem cell transplant (alloHCT). Contemporary salvage regimens used as a bridge to transplant have expanded to include not only non-cross resistant chemotherapy, but also brentuximab vedotin (BV) and checkpoint inhibitors (CPI). As the management of relapsed/refractory (R/R) cHL evolves with the introduction of novel agents, so too does the role of transplantation. The paradigm of chemosensitivity as a predictor for autoHCT efficacy is being challenged by favorable post- autoHCT outcomes in heavily pre-treated CPI-exposed patients. Contemporary supportive care measures, validated comorbidity assessments, and an increased donor pool with haploidentical donors have broadened the application of transplantation to an increasingly older and diverse patient population. Despite the introduction of increasingly effective treatment options for R/R cHL, transplantation continues to play an important role in the management of these patients. In this review, we explore the impact of salvage therapy on autoHCT, conditioning regimens, maintenance therapy and the diminishing role of alloHCT for patients with cHL.

Checkpoint Inhibitors and the Changing Face of the Relapsed/Refractory Classical Hodgkin Lymphoma Pathway

PURPOSE OF REVIEW

Checkpoint inhibitors (CPIs) targeting PD1 are highly active in relapsed/refractory classical Hodgkin lymphoma. A plethora of recent studies, often small and non-randomised, have raised many questions about how to optimally integrate these into clinical practice. We aim to discuss the use of CPIs in different relapsed/refractory settings in an effort to better define their role and highlight areas of research.

RECENT FINDINGS

CPIs have shown efficacy at first relapse, as salvage pre- and post-autologous (ASCT) and allogeneic stem cell transplant (alloSCT) and as maintenance post-ASCT. Immune-related adverse events require careful attention, especially when used peri-alloSCT, where it is associated with hyperacute graft-versus-host disease. Newer PD1 inhibitors, as well as strategies to overcome CPI resistance, are being tested. CPIs are increasingly deployed at earlier points in the classical Hodgkin lymphoma pathway. Whilst progress is clearly being made, randomised studies are required to more clearly define the optimal positioning of these agents.