The Advanced-Stage Hodgkin Lymphoma International Prognostic Index: Development and Validation of a Clinical Prediction Model From the HoLISTIC Consortium

Prediction of breast cancer risk for adolescents and young adults with Hodgkin lymphoma

BACKGROUND

Although female survivors of Hodgkin lymphoma (HL) have an increased risk of breast cancer (BC), no BC risk prediction model is available. We developed such models incorporating mean radiation dose to the breast or breast quadrant-specific radiation doses.

METHODS

Relative risks and age-specific incidence for BC and competing events (mortality or other subsequent cancer) were estimated from 1194 Dutch 5-year HL survivors, treated at ages 11-40 during 1965-2000. Predictors were doses to 10 breast segments or mean breast radiation dose, BC family history, year of and age at HL diagnosis, and ages at menopause and first live birth. Models were independently validated using US Childhood Cancer Survivor Study cohort participants.

RESULTS

Predicted absolute BC risks 25 years after HL diagnosis ranged from 1.0% for survivors diagnosed at ages 20-24 with less than 10 Gy mean breast radiation dose and who were menopausal 5 years after HL diagnosis, to 22.0% for survivors 25-29 years at diagnosis, with at least 25 Gy mean breast dose and no menopause within 5 years. In external validation, the observed/expected BC case ratio was 1.19 (95% confidence interval 0.97 to 1.47) for the breast segment-specific dose model, and 1.29 (1.05 to 1.60) for the mean breast dose model. The areas under the receiver operating characteristic curve were 0.68 (0.63 to 0.74) and 0.68 (0.62 to 0.73), respectively.

CONCLUSION

Breast segment-specific or mean breast radiation dose with personal and clinical characteristics predicted absolute BC risk in HL survivors with moderate discrimination but good calibration, rendering the models useful for clinical decision-making.

Computational pathology identifies a low B-cell content in the tumour microenvironment as a predictor of adverse outcome in patients with classic Hodgkin lymphoma treated with ABVD

AIMS

The prognostic impact of B lymphocytes surrounding Hodgkin and Reed Sternberg (HRS) cells in classic Hodgkin lymphoma (cHL) and pathogenic variants in genes associated with apoptosis regulation remains undefined.

METHODS

We have quantified the proportion of B lymphocytes in tumour microenvironment (TME) in 220 diagnostic slides from 110 cHL patients applying computational pathology (CP) and sequenced cases using a targeted panel including 47 genes recurrently mutated in mature B-cell neoplasms. Kaplan-Meier estimators and multivariate Cox regression on overall survival (OS) and progression-free survival (PFS) were assessed following the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis guidelines.

RESULTS

The mean percentage of B lymphocytes was 45.1 (SD: 24.8). Genes recurrently affected by nonsynonymous somatic mutations in 25% or more of patients included EP300, NOTCH and ABL1. A lower number of mutations were discovered in Epstein-Barr virus-positive cHL (21.1% vs 78.8%) reinforcing the notion that viral infection could functionally replace the need for genomic aberrations. Classic Hodgkin lymphoma (cHL) patients that jointly presented a reduction in the number of B lymphocytes in TME (<8%) and the absence of mutations in apoptosis-associated genes (ABL1, BIRC3, CASP8 and FAS) presented a lower OS (mean OS: 31.5 months, 95% CI: 0 to 69.7 months) in comparison with patients without this event (mean OS: 84.7 months, 95% CI: 61.9 to 107.5 months) (p=0.01). This high-risk cHL subgroup also presented a significantly lower PFS (mean PFS: 8.5 months, 95% CI: 7.5 to 9.5 months) in comparison with B-cell-enriched or apoptosis-mutated cHL (mean PFS: 55.2 months; 95% CI: 42.4 to 68 months) (p<0.001).

CONCLUSIONS

This study expands previous data on the value of CP in cHL, and specifically, the distribution of B cells, identifying patients with an increased risk of treatment failure and progression. Furthermore, immune escape by apoptosis dysregulation during clonal selection occurring in germinal centres constitutes a landmark of cHL. These results could be the basis for further development of targeted therapies directed against apoptosis modulators in cHL.

External validation and calibration of the HoLISTIC Consortium's advanced-stage Hodgkin lymphoma international prognostic index (A-HIPI) in the Brazilian Hodgkin lymphoma registry

The Hodgkin lymphoma International Study for Individual Care (HoLISTIC) Consortium's A-HIPI model, developed in 2022 for advanced-stage classical Hodgkin lymphoma (cHL), predicts survival within 5 years amongst newly diagnosed patients. This study validates its performance in the Brazilian Hodgkin lymphoma registry. By 2022, the Brazilian HL registry included 1357 cHL patients, with a median 5-year follow-up. Probabilities for 5-year progression-free survival (PFS) and overall survival (OS) were calculated using A-HIPI-model equations. Discrimination (Harrell C-statistic/Uno C-statistic) and calibration measures assessed external validation and calibration. Lab values beyond the allowed range were excluded, mirroring the initial A-HIPI analysis. A total of 694 advanced-stage cHL patients met the original inclusion criteria (age 18-65 years, Stage IIB-IV). Median age was 31 years; 46.3% were females. Stage distribution was IIB (33.1%), III (27.4%), IV (39.5%). Bulky disease in 32.6%. Five-year PFS and OS were 68.4% and 86.0%, respectively. Harrell C-statistics were 0.60 for PFS and 0.69 for OS, and Uno C-statistics were 0.63 for PFS and 0.72 for OS. Calibration plots demonstrated well-calibrated predictions with calibration slopes of 0.91 and 1.03 for 5-year OS and PFS, respectively. Despite differing patient, clinical characteristics, and socioeconomic factors, the baseline prediction tool performed well in the Brazilian cohort, demonstrating adequate discrimination and calibration. This supports its reliability in diverse settings.

Whole slide imaging of tumour microenvironment in classical Hodgkin's lymphoma: development of a clinical prediction model based on programmed death-ligand 1 and tumorous Reed-Sternberg cells

AIMS

The prognostic impact of programmed death-ligand 1 (PD-L1) cells in classic Hodgkin lymphoma (cHL) tumour microenvironment remains undefined.

METHODS

Model development via Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis guidelines were followed. PD-L1+ and CD30+ tumoral Reed-Sternberg cells were quantified through whole slide imaging and digital image analysis in 155 digital histopathological slides of cHL. Univariate and multivariate survival analyses were performed. The analyses were reproduced for patients with advanced stages (IIB, III and IV) using the Advanced-stage cHL International Prognostic Index.

RESULTS

The PD-L1/CD30 ratio was statistically significantly associated with survival outcomes. Patients with a PD-L1/CD30 ratio above 47.1 presented a shorter overall survival (mean OS: 53.7 months; 95% CI: 28.7 to 78.7) in comparison with patients below this threshold (mean OS: 105.4 months; 95% CI: 89.6 to 121.3) (p=0.04). When adjusted for covariates, the PD-L1/CD30 ratio retained prognostic impact, both for the OS (HR: 1.005; 95% CI: 1.002 to 1.008; p=0.000) and the progression-free survival (HR: 3.442; 95% CI: 1.045 to 11.340; p=0.04) in a clinical and histopathological multivariate model including the male sex (HR: 3.551; 95% CI: 0.986 to 12.786; p=0.05), a percentage of tumoral cells ≥10.1% (HR: 1.044; 95% CI: 1.003 to 1.087; p=0.03) and high risk International Prognostic Score (≥3 points) (HR: 6.453; 95% CI: 1.970 to 21.134; p=0.002).

CONCLUSIONS

The PD-L1/CD30 ratio identifies a group of cHL patients with an increased risk of treatment failure. Its clinical application can be performed as it constitutes an easy to implement pathological information in the diagnostic work-up of patients with cHL.

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.

A new scoring system to predict survival in elderly advanced stage Hodgkin lymphoma patients

Predictive prognostic scoring (PS) systems are not primarily applicable to elderly patients with classical Hodgkin lymphoma (cHL). The objective of this study was to develop a PS system for these patients. The derivation cohort (DC) was utilized for model development, consisting of 97 variables. The resulting algorithm was named as Hodgkin's Lymphoma Early Death in the Elderly within 12 months (HEDEL12). Internal and external validation cohorts (IVC and EVC) were employed for validation. A total of 286 patients were evaluated retrospectively. In DC 38 of 178 patients died within the first 12 months and overall survival (OS) at 12-month was 78.6%. Independent predictors of HEDEL12 were female sex, low albumin levels (<3.5 g/dL), and ECOG scores 2-4. According to HEDEL12 scores 0-1, OS at 12- months were 89.8% and 91.0% for IVC and EVC, respectively. The HEDEL12 scoring is useful in predicting the survival of advanced-stage cHL patients.

Baseline prognostic predictors in classical Hodgkin Lymphoma: a retrospective, single-center analysis on patients treated with PET/CT-guided ABVD

Introduction

The identification of baseline prognostic factors in Classical Hodgkin Lymphoma could help in tailoring a risk-based approach as the therapeutic landscape expands. Currently, the International Prognostic Score (IPS) represents the most used prediction tool in clinical practice, but other potential baseline risk predictors have been identified.

Methods

We performed a retrospective analysis in a cohort of 274 patients treated with 18FDG-PET/CT-guided ABVD to assess the prognostic significance of the IPS risk factors, and to validate the impact of the peripheral blood lymphocyte to monocyte (LMR) and neutrophil to lymphocyte (NLR) ratios on prognosis definition.

Results

Among the considered risk factors, stage IV disease (HR 1.83), leukocytosis (HR 2.28), anemia (HR 3.23) and low LMR (HR 2.01) significantly predicted PFS, whereas male sex (HR 2.93), stage IV disease (HR 3.00) and lymphopenia (HR 7.84) significantly predicted OS. A 4 variable and a 3 variable prognostic system was subsequently proposed for PFS and OS, respectively. In both cases, a stark decrease in the survival probability was documented as the score increased. Moreover, by selecting only the significant IPS items and considering a more recently proposed prognostic factor (LMR) we were able to better identify patients at higher risk of relapsing after PET/CT-guided ABVD.

Discussion

Although the IPS was still able to identify a subgroup of high-risk patients within our cohort of individuals treated with PET/CT-guided ABVD, not all the risk factors that it considers were found to have an impact on survival times. Moreover, by selecting only the significant IPS items and considering a more recently proposed prognostic factor (LMR) we were able to better identify patients at higher risk of relapse, in an effort to contribute to the building of a modern risk prediction tool that can help guide treatment choices.

Construction and validation of a clinical risk model based on machine learning for screening characteristic factors of lymphovascular space invasion in endometrial cancer

This study aimed to identify factors that affect lymphovascular space invasion (LVSI) in endometrial cancer (EC) using machine learning technology, and to build a clinical risk assessment model based on these factors. Samples were collected from May 2017 to March 2022, including 312 EC patients who received treatment at Xuzhou Medical University Affiliated Hospital of Lianyungang. Of these, 219 cases were collected for the training group and 93 for the validation group. Clinical data and laboratory indicators were analyzed. Logistic regression and least absolute shrinkage and selection operator (LASSO) regression were used to analyze risk factors and construct risk models. The LVSI and non-LVSI groups showed statistical significance in clinical data and laboratory indicators (P < 0.05). Multivariable logistic regression analysis identified independent risk factors for LVSI in EC, which were myometrial infiltration depth, cervical stromal invasion, lymphocyte count (LYM), monocyte count (MONO), albumin (ALB), and fibrinogen (FIB) (P < 0.05). LASSO regression identified 19 key feature factors for model construction. In the training and validation groups, the risk scores for the logistic and LASSO models were significantly higher in the LVSI group compared with that in the non-LVSI group (P < 0.001). The model was built based on machine learning and can effectively predict LVSI in EC and enhance preoperative decision-making. The reliability of the model was demonstrated by the significant difference in risk scores between LVSI and non-LVSI patients in both the training and validation groups.

Harnessing multi-source data for individualized care in Hodgkin Lymphoma

Hodgkin lymphoma is a rare, but highly curative form of cancer, primarily afflicting adolescents and young adults. Despite multiple seminal trials over the past twenty years, there is no single consensus-based treatment approach beyond use of multi-agency chemotherapy with curative intent. The use of radiation continues to be debated in early-stage disease, as part of combined modality treatment, as well as in salvage, as an important form of consolidation. While short-term disease outcomes have varied little across these different approaches across both early and advanced stage disease, the potential risk of severe, longer-term risk has varied considerably. Over the past decade novel therapeutics have been employed in the retrieval setting in preparation to and as consolidation after autologous stem cell transplant. More recently, these novel therapeutics have moved to the frontline setting, initially compared to standard-of-care treatment and later in a direct head-to-head comparison combined with multi-agent chemotherapy. In 2018, we established the HoLISTIC Consortium, bringing together disease and methods experts to develop clinical decision models based on individual patient data to guide providers, patients, and caregivers in decision-making. In this review, we detail the steps we followed to create the master database of individual patient data from patients treated over the past 20 years, using principles of data science. We then describe different methodological approaches we are taking to clinical decision making, beginning with clinical prediction tools at the time of diagnosis, to multi-state models, incorporating treatments and their response. Finally, we describe how simulation modeling can be used to estimate risks of late effects, based on cumulative exposure from frontline and salvage treatment. The resultant database and tools employed are dynamic with the expectation that they will be updated as better and more complete information becomes available.

Immune checkpoint inhibitors in advanced and relapsed/refractory Hodgkin lymphoma: current applications and future prospects

Classic Hodgkin lymphoma (cHL) treatment paradigms are undergoing a shift with the integration of immune checkpoint inhibitors (ICIs) into both first-line and relapsed/refractory (R/R) regimens. In first-line therapy, the synergy between ICIs and chemotherapy may surpass the previous standards of ABVD and BV-AVD established by landmark trials including RATHL and ECHELON-1. In R/R disease, the combination of ICIs with chemotherapy has begun to challenge the paradigm of chemotherapy as a bridge to consolidative autologous stem cell transplantation. The clinical advances heralded by ICI offer unique challenges to management. ICI treatment and the associated inflammatory response can make the traditional timing and modalities of treatment response assessment difficult to interpret. In contrast to ABVD and BV-AVD, pembrolizumab-AVD results in PET2 positivity rates that are higher and less predictive of treatment response even when ultimate outcomes may be superior. This suggests that the predictive value of PET2 may be less reliable in the ICI era, prompting a reevaluation of response assessment strategies. Looking forward, circulating tumor DNA (ctDNA) may be a promising tool in response-adapted therapy. Its potential to complement or even supersede PET scans in predicting response to ICIs represents a critical advancement. The integration of ctDNA analysis holds the promise of refining response-adapted approaches and enhancing precision in therapeutic decision-making for patients with cHL. This review navigates the evolving landscape of cHL therapy, emphasizing the paradigmatic shift brought about by ICIs. This article explores the impact of combining ICIs with chemotherapy in both relapsed/refractory and first-line settings, scrutinizes the challenges posed to response-adapted therapy by ICIs, and highlights the potential role of ctDNA as an adjunct in refining response-adapted strategies for cHL.

Machine Learning-Based Survival Prediction Models for Progression-Free and Overall Survival in Advanced-Stage Hodgkin Lymphoma

PURPOSE

Patients diagnosed with advanced-stage Hodgkin lymphoma (aHL) have historically been risk-stratified using the International Prognostic Score (IPS). This study investigated if a machine learning (ML) approach could outperform existing models when it comes to predicting overall survival (OS) and progression-free survival (PFS).

PATIENTS AND METHODS

This study used patient data from the Danish National Lymphoma Register for model development (development cohort). The ML model was developed using stacking, which combines several predictive survival models (Cox proportional hazard, flexible parametric model, IPS, principal component, penalized regression) into a single model, and was compared with two versions of IPS (IPS-3 and IPS-7) and the newly developed aHL international prognostic index (A-HIPI). Internal model validation was performed using nested cross-validation, and external validation was performed using patient data from the Swedish Lymphoma Register and Cancer Registry of Norway (validation cohort).

RESULTS

In total, 707 and 760 patients with aHL were included in the development and validation cohorts, respectively. Examining model performance for OS in the development cohort, the concordance index (C-index) for the ML model, IPS-7, IPS-3, and A-HIPI was found to be 0.789, 0.608, 0.650, and 0.768, respectively. The corresponding estimates in the validation cohort were 0.749, 0.700, 0.663, and 0.741. For PFS, the ML model achieved the highest C-index in both cohorts (0.665 in the development cohort and 0.691 in the validation cohort). The time-varying AUCs for both the ML model and the A-HIPI were consistently higher in both cohorts compared with the IPS models within the first 5 years after diagnosis.

CONCLUSION

The new prognostic model for aHL on the basis of ML techniques demonstrated a substantial improvement compared with the IPS models, but yielded a limited improvement in predictive performance compared with the A-HIPI.

Pathogenic Variants Associated with Epigenetic Control and the NOTCH Pathway Are Frequent in Classic Hodgkin Lymphoma

Classic Hodgkin lymphoma (cHL) constitutes a B-cell neoplasm derived from germinal center lymphocytes. Despite high cure rates (80-90%) obtained with the current multiagent protocols, a significant proportion of cHL patients experience recurrences, characterized by a lower sensitivity to second-line treatments. The genomic background of chemorefractory cHL is still poorly understood, limiting personalized treatment strategies based on molecular features. In this study, using a targeted next-generation sequencing (NGS) panel specifically designed for cHL research, we compared chemosensitive and chemorefractory diagnostic tissue samples of cHL patients. Furthermore, we longitudinally examined paired diagnosis-relapsesamples of chemorefractory cHL in order to define patterns of dynamic evolution and clonal selection. Pathogenic variants in NOTCH1 and NOTCH2 genes frequently arise in cHL. Mutations in genes associated with epigenetic regulation (CREBBP and EP300) are particularly frequent in relapsed/refractory cHL. The appearance of novel clones characterized by mutations previously not identified at diagnosis is a common feature in cHL cases showing chemoresistance to frontline treatments. Our results expand current molecular and pathogenic knowledge of cHL and support the performance of molecular studies in cHL prior to the initiation of first-line therapies.

Classic Hodgkin Lymphoma in Adolescents and Young Adults

Hodgkin lymphoma (HL) represents one of the more common cancers occurring in adolescent and young adults (AYAs) age 15-39 years. Despite a generally high cure rate, age-related differences in HL biology and the optimal therapeutic approaches including supportive care and risks for long-term adverse effects in the AYA population remain understudied. After an overview of HL epidemiology and biology in the AYA population, this review will cover frontline pediatric and adult treatment approaches. Recently completed and ongoing studies will foster harmonization of risk group definition and trial eligibility criteria across the AYA spectrum, enabling more rapid progress. In addition to treatment approaches, an evolving holistic care approach to AYA HL will result in enhanced understanding of unique challenges, and continued improved short- and long-term outcome for these patients.

Prognostic Impact of Serum β2-Microglobulin Levels in Hodgkin Lymphoma Treated with ABVD or Equivalent Regimens: A Comprehensive Analysis of 915 Patients

The significance of serum beta-2 microglobulin (sβ2m) in Hodgkin lymphoma (HL) is controversial. We analyzed 915 patients with HL, who were treated with ABVD or equivalent regimens with or without radiotherapy. Sβ2m levels were measured by a radioimmunoassay (upper normal limit 2.4 mg/L). Sequential cutoffs (1.8-3.0 by 0.1 mg/L increments, 3.5 and 4.0 mg/L) were tested along with ROC analysis. The median sβ2m levels were 2.20 mg/L and were elevated (>2.4 mg/L) in 383/915 patients (41.9%). Higher sβ2m was associated with inferior freedom from progression (FFP) at all tested cutoffs. The best cutoff was 2.0 mg/L (10-year FFP 83% vs. 70%, p = 0.001), which performed better than the 2.4 mg/L cutoff ("normal versus high"). In multivariate analysis, sβ2m > 2.0 mg/L was an independent adverse prognostic factor in the whole patient population. In multivariate overall survival analysis, sβ2m levels were predictive at 2.0 mg/L cutoff in the whole patient population and in advanced stages. Similarly, sβ2m > 2.0 mg/L independently predicted inferior HL-specific survival in the whole patient population. Our data suggest that higher sβ2m is an independent predictor of outcome in HL but the optimal cutoff lies within the normal limits (i.e., at 2.0 mg/L) in this predominantly young patient population, performing much better than a "normal versus high" cutoff set at 2.4 mg/L.

Impact of cumulative dose of brentuximab vedotin on outcomes of frontline therapy for advanced-stage Hodgkin lymphoma

In the pivotal study ECHELON-1, brentuximab vedotin (BV), doxorubicin, vinblastine, and dacarbazine (A + AVD) demonstrated superior efficacy compared with bleomycin + AVD for the treatment of advanced-stage classic Hodgkin lymphoma (cHL). However, there are minimal available data regarding the frequency of dose reductions or omission of BV during curative therapy and the potential impact on patient outcomes. In a real-world analysis, we retrospectively reviewed the characteristics and outcomes of 179 patients with stage III or IV cHL treated with frontline A + AVD from January 2010 to April 2022. Treatment consisted of up to 1.2 mg/kg of BV and standard dose AVD IV on days 1 and 15 of each 28-day cycle for up to 6 cycles. At the time of treatment, the median patient age was 37 years, and a high-risk International Prognostic Score was observed in 46% of patients. Overall, 91% of patients received 6 cycles of AVD; 55% of patients did not receive the intended cumulative dose of BV (CDB); 28% of patients received two-thirds or less than the planned CDB. At a median follow-up time of 27.4 months (95% confidence interval [CI], 24.8-29), the median progression-free survival (PFS) was not reached, and the 12-month PFS was 90.3% (95% CI, 85.9-95.0). The impact of CDB on PFS was not significant (P = .15), nor was high CDB significantly associated with increased adverse events. In real-world experience, A + AVD is a highly effective treatment for patients with advanced-stage cHL, including for patients with prominent dose reductions of BV.

Hodgkin lymphoma treatment for older persons in the modern era

There has been a renewed effort globally in the study of older Hodgkin lymphoma (HL) patients, generating a multitude of new data. For prognostication, advancing age, comorbidities, altered functional status, Hispanic ethnicity, and lack of dose intensity (especially without anthracycline) portend inferior survival. Geriatric assessments (GA), including activities of daily living (ADL) and comorbidities, should be objectively measured in all patients. In addition, proactive multidisciplinary medical management is recommended (eg, geriatrics, cardiology, primary care), and pre-phase therapy should be considered for most patients. Treatment for fit older HL patients should be given with curative intent, including anthracyclines, and bleomycin should be minimized (or avoided). Brentuximab vedotin given sequentially before and after doxorubicin, vinblastine, dacarbazine (AVD) chemotherapy for untreated patients is tolerable and effective, and frontline checkpoint inhibitor/AVD platforms are rapidly emerging. Therapy for patients who are unfit or frail, whether due to comorbidities and/or ADL loss, is less clear and should be individualized with consideration of attenuated anthracycline-based therapy versus lower-intensity regimens with inclusion of brentuximab vedotin +/- checkpoint inhibitors. For all patients, there should be clinical vigilance with close monitoring for treatment-related toxicities, including neurotoxicity, cardiopulmonary, and infectious complications. Finally, active surveillance for "postacute" complications 1 to 10 years post therapy, especially cardiac disease, is needed for cured patients. Altogether, therapy for older HL patients should include anthracycline-based therapy in most cases, and novel targeted agents should continue to be integrated into treatment paradigms, with more research needed on how best to utilize GAs for treatment decisions.

Prognostic Markers within the Tumour Microenvironment in Classical Hodgkin Lymphoma

Classical Hodgkin lymphoma (cHL) accounts for 0.4% of all new cancer cases globally. Despite high cure rates with standard treatment, approximately 15% of patients still experience relapsed or refractory (RR) disease, and many of these eventually die from lymphoma-related causes. Exciting new targeted agents such as anti-PD-1 agents and brentuximab vedotin have changed the therapeutic paradigm beyond chemotherapy and radiotherapy alone. Advances in understanding of the molecular biology are providing insights in the context of novel therapies. The signature histology of cHL requires the presence of scant malignant Hodgkin Reed-Sternberg cells (HRSCs) surrounded by a complex immune-rich tumour microenvironment (TME). The TME cellular composition strongly influences outcomes, yet knowledge of the precise characteristics of TME cells and their interactions with HRSCs is evolving. Novel high-throughput technologies and single-cell sequencing allow deeper analyses of the TME and mechanisms elicited by HRSCs to propagate growth and avoid immune response. In this review, we explore the evolution of knowledge on the prognostic role of immune cells within the TME and provide an up-to-date overview of emerging prognostic data on cHL from new technologies that are starting to unwind the complexity of the cHL TME and provide translational insights into how to improve therapy in the clinic.

Clinical applications of circulating tumor DNA in Hodgkin lymphoma

Hodgkin lymphoma is a B-cell lymphoma often affecting young adults. Outcomes following intensive chemo- and radiotherapy are generally favourable but leave patients at high risk for early and late toxicities frequently reducing quality of life. Relapsed/refractory disease is regularly difficult to treat and ultimately results in death in a relevant subset of patients. Current strategies for risk stratification and response evaluation rely on clinical features and imaging only, and lack discriminatory power to detect patients at risk for disease progression. Here, we explore how circulating tumor DNA sequencing might help to overcome these shortcomings. We provide an overview over recent technical and methodological developments and suggest potential use cases for different clinical situations. Circulating tumor DNA sequencing offers the potential to significantly augment current risk stratification strategies with the ultimate goal of further individualizing treatment strategies for patients with HL.