Positron Emission Tomography-Guided Therapy of Aggressive Non-Hodgkin Lymphomas (PETAL): A Multicenter, Randomized Phase III Trial

Validation of an Artificial Intelligence-Based Prediction Model Using 5 External PET/CT Datasets of Diffuse Large B-Cell Lymphoma

The aim of this study was to validate a previously developed deep learning model in 5 independent clinical trials. The predictive performance of this model was compared with the international prognostic index (IPI) and 2 models incorporating radiomic PET/CT features (clinical PET and PET models). Methods: In total, 1,132 diffuse large B-cell lymphoma patients were included: 296 for training and 836 for external validation. The primary outcome was 2-y time to progression. The deep learning model was trained on maximum-intensity projections from PET/CT scans. The clinical PET model included metabolic tumor volume, maximum distance from the bulkiest lesion to another lesion, SUVpeak, age, and performance status. The PET model included metabolic tumor volume, maximum distance from the bulkiest lesion to another lesion, and SUVpeak Model performance was assessed using the area under the curve (AUC) and Kaplan-Meier curves. Results: The IPI yielded an AUC of 0.60 on all external data. The deep learning model yielded a significantly higher AUC of 0.66 (P < 0.01). For each individual clinical trial, the model was consistently better than IPI. Radiomic model AUCs remained higher for all clinical trials. The deep learning and clinical PET models showed equivalent performance (AUC, 0.69; P > 0.05). The PET model yielded the highest AUC of all models (AUC, 0.71; P < 0.05). Conclusion: The deep learning model predicted outcome in all trials with a higher performance than IPI and better survival curve separation. This model can predict treatment outcome in diffuse large B-cell lymphoma without tumor delineation but at the cost of a lower prognostic performance than with radiomics.

Identification, risk factors, and clinical course of CNS relapse in DLBCL patients across 19 prospective phase 2 and 3 trials-a LYSA and GLA/ DSHNHL collaboration

Progression or relapse in the central nervous system (CNS) remains a rare but mostly fatal event for patients with diffuse large B-cell lymphoma (DLBCL). In a retrospective analysis of 5189 patients treated within 19 prospective German and French phase 2/3 trials, we identified 159 patients experiencing a CNS event (relapse: 62%, progression: 38%). Intracerebral, meningeal, intraspinal, or combined involvement was reported in 44%, 31%, 3%, and 22% of patients, respectively. 62 of 155 evaluable patients (40%) showed concurrent systemic progression/ relapse. 82% of all CNS events occurred within two years after study inclusion or randomization. 87% of patients showed extranodal involvement outside the CNS. Patients generally had poor outcomes with a median overall survival (OS) of 3.4 months (95% CI 2.9-4.2) and a 2-year OS of 15% (10-22%). Outcomes did not differ depending on the site or time point of CNS events. Patients with isolated CNS events demonstrated significantly better OS (p = 0.023). Twenty-five patients were consolidated with autologous or allogeneic stem cell transplantation and achieved a 3-year OS of 36% (20-66%). This large study including more than 5000 DLBCL patients highlights the unmet medical need to improve the outcome of DLBCL patients suffering from CNS relapse.

Comparative effectiveness of 6x R-CHOP21 versus 6x R-CHOP21 + 2 R for patients with advanced-stage diffuse large B-cell lymphoma

First-line treatment for advanced-stage diffuse large B-cell lymphoma (DLBCL) typically involves 6x R-CHOP21 or 6x R-CHOP21 with two additional rituximab administrations (6x R-CHOP21 + 2 R). In contemporary practice, this treatment choice might be guided by interim PET scan results. This nationwide, population-based study investigates the comparative effectiveness of these treatment regimens in an era where interim PET-guided treatment decisions were not standard practice. Utilizing the Netherlands Cancer Registry, we identified 1577 adult patients diagnosed with advanced-stage DLBCL between 2014-2018 who completed either 6x R-CHOP21 (43%) or 6x R-CHOP21 + 2 R (57%). We used propensity scores to assess differences in event-free survival (EFS) and overall survival (OS). At five years, EFS (hazard ratio of 6x R-CHOP21 + 2 R versus 6x R-CHOP21 [HR] = 0.89; 95% confidence interval [CI], 0.72-1.09) and OS (HR = 0.93; 95% CI, 0.73-1.18) were not significantly different between both regimens. In exploratory risk-stratified analysis according to the International Prognostic Index (IPI), high-IPI patients (i.e., scores of 4-5) benefit most from 6x R-CHOP21 + 2 R (5-year absolute risk difference of EFS = 16.8%; 95% CI, -0.4%-34.1% and OS = 12.1%; 95% CI, -5.4-29.6%). Collectively, this analysis reveals no significant differences on average in EFS and OS between the two treatments. However, the potential benefits for high-risk patients treated with 6x R-CHOP21 + 2 R underscore the need for future research.

Patient-Reported Outcomes in Phase 3 Clinical Trials for Blood Cancers: A Systematic Review

Importance

Published research suggests that patient-reported outcomes (PROs) are neither commonly collected nor reported in randomized clinical trials (RCTs) for solid tumors. Little is known about these practices in RCTs for hematological malignant neoplasms.

Objective

To evaluate the prevalence of PROs as prespecified end points in RCTs of hematological malignant neoplasms, and to assess reporting of PROs in associated trial publications.

Evidence Review

All issues of 8 journals known for publishing high-impact RCTs (NEJM, Lancet, Lancet Hematology, Lancet Oncology, Journal of Clinical Oncology, Blood, JAMA, and JAMA Oncology) between January 1, 2018, and December 13, 2022, were searched for primary publications of therapeutic phase 3 trials for adults with hematological malignant neoplasms. Studies that evaluated pretransplant conditioning regimens, graft-vs-host disease treatment, or radiotherapy as experimental treatment were excluded. Data regarding trial characteristics and PROs were extracted from manuscripts and trial protocols. Univariable analyses assessed associations between trial characteristics and PRO collection or reporting.

Findings

Ninety RCTs were eligible for analysis. PROs were an end point in 66 (73%) trials: in 1 trial (1%) as a primary end point, in 50 (56%) as a secondary end point, and in 15 (17%) as an exploratory end point. PRO data were reported in 26 of 66 primary publications (39%): outcomes were unchanged in 18 and improved in 8, with none reporting worse PROs with experimental treatment. Trials sponsored by for-profit entities were more likely to include PROs as an end point (49 of 55 [89%] vs 17 of 35 [49%]; P < .001) but were not significantly more likely to report PRO data (20 of 49 [41%] vs 6 of 17 [35%]; P = .69). Compared with trials involving lymphoma (18 of 29 [62%]) or leukemia or myelodysplastic syndrome (18 of 28 [64%]), those involving plasma cell disorders or multiple myeloma (27 of 30 [90%]) or myeloproliferative neoplasms (3 of 3 [100%]) were more likely to include PROs as an end point (P = .03). Similarly, compared with trials involving lymphoma (3 of 18 [17%]) or leukemia or myelodysplastic syndrome (5 of 18 [28%]), those involving plasma cell disorders or multiple myeloma (16 of 27 [59%]) or myeloproliferative neoplasms (2 of 3 [67%]) were more likely to report PROs in the primary publication (P = .01).

Conclusions and Relevance

In this systematic review, almost 3 of every 4 therapeutic RCTs for blood cancers collected PRO data; however, only 1 RCT included PROs as a primary end point. Moreover, most did not report resulting PRO data in the primary publication and when reported, PROs were either better or unchanged, raising concern for publication bias. This analysis suggests a critical gap in dissemination of data on the lived experiences of patients enrolled in RCTs for hematological malignant neoplasms.

Circulating Tumor DNA in Diffuse Large B-Cell Lymphoma: from Bench to Bedside?

OPINION STATEMENT

Diffuse large B-cell lymphoma (DLBCL) is a curable disease with variable outcomes due to underlying heterogeneous clinical and molecular features-features that are insufficiently characterized with our current tools. Due to these limitations, treatment largely remains a "one-size-fits-all" approach. Circulating tumor DNA (ctDNA) is a novel biomarker in cancers that is increasingly utilized for risk stratification and response assessment. ctDNA is readily detectable from the plasma of patients with DLBCL but has not yet been incorporated into clinical care to guide treatment. Here, we describe how ctDNA sequencing represents a promising technology in development to personalize the care of patients with DLBCL. We will review the different types of ctDNA assays being studied and the rapidly growing body of evidence supporting the utility of ctDNA in different treatment settings in DLBCL. Risk stratification by estimation of tumor burden and liquid genotyping, molecular response assessment during treatment, and monitoring for measurable residual disease (MRD) to identify therapy resistance and predict clinical relapse are all potential applications of ctDNA. It is time for clinical trials in DLBCL to utilize ctDNA as an integral biomarker for patient selection, response-adapted designs, and surrogate endpoints. As more ctDNA assays become commercially available for routine use, clinicians should consider liquid biopsy when treatment response is equivocal on imaging. Incorporating MRD may also guide decision-making if patients experience severe treatment toxicities. Though important barriers remain, we believe that ctDNA will soon be ready to transition from bench to bedside to individualize treatment for our patients with DLBCL.

Quarter-Century PET/CT Transformation of Oncology: Lymphoma

The clinical landscape of lymphomas has changed dramatically over the last 2 decades, including significant progress made in the understanding and utilization of imaging modalities and the available treatment options for both indolent and aggressive lymphomas. Since the introduction of hybrid PET/CT scanners in 2001, the indications of 18F-fluorodeoxyglucose (FDG) PET/CT in the management of lymphomas have grown rapidly. In today's clinical practice, FDG PET/CT is used in successful management of the vast majority patients with lymphomas.

New Insights into First-Line Therapy in Diffuse Large B-Cell Lymphoma: Are We Improving Outcomes?

Diffuse large B-cell lymphoma (DLBCL) is the most prevalent subtype of lymphoma, comprising heterogeneous patient subgroups with distinctive biological and clinical characteristics. The R-CHOP combination (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) has been the standard initial treatment, yielding prolonged remissions in over 60% of patients with advanced-stage disease. Several attempts to enhance the outcomes of this regimen over the last two decades have shown limited success. Various novel therapeutic approaches have recently emerged in lymphoma, demonstrating promising results. These include small molecules, novel monoclonal antibodies, antibody-drug conjugates (ADC), bispecific antibodies (BsAbs), and chimeric antigen receptor (CAR) T-cell therapy. This review explores recent advancements in therapeutic strategies for DLBCL and their potential impact on the initial management of DLBCL patients.

Evaluation of therapeutic effect and prognostic value of 18F-FDG PET/CT in different treatment nodes of DLBCL patients

BACKGROUND

In the present study, we aimed to investigate the role of baseline (B), interim (I) and end-of-treatment (Eot) 18F-FDG PET/CT in assessing the prognosis of diffuse large B cell lymphoma (DLBCL), so as to identify patients who need intensive treatment at an early stage.

METHODS

A total of 127 DLBCL patients (62 men; 65 women; median age 62 years) were retrospectively analyzed in this study. Baseline (n = 127), interim (n = 127, after 3-4 cycles) and end-of-treatment (n = 53, after 6-8 cycles) PET/CT images were re-evaluated; semi-quantitative parameters such as maximum standardized uptake value of lesion-to-liver ratio (SUVmax(LLR)) and lesion-to-mediastinum ratio (SUVmax(LMR)), total metabolic tumor volume (TMTV) and total metabolic tumor volume (TLG) were recorded. ΔTLG1 was the change of interim relative to baseline TLG (I to B), ΔTLG2 (Eot to B). ΔSUVmax and ΔTMTV were the same algorithm. The visual Deauville 5-point scale (D-5PS) has been adopted as the major criterion for PET evaluation. Visual analysis (VA) and semi-quantitative parameters were assessed for the ability to predict progression-free survival (PFS) and overall survival (OS) by using Kaplan-Meier method, cox regression and logistic regression analysis. When visual and semi-quantitative analysis are combined, the result is only positive if both are positive.

RESULTS

At a median follow-up of 34 months, the median PFS and OS were 20 and 32 months. The survival curve analysis showed that advanced stage and IPI score with poor prognosis, ΔSUVmax(LLR)1 < 89.2%, ΔTMTV1 < 91.8% and ΔTLG1 < 98.8%, ΔSUVmax(LLR)2 < 86.4% were significantly related to the shortening of PFS in patient (p < 0.05). ΔSUVmax(LLR)1 < 83.2% and ΔTLG1 < 97.6% were significantly correlated with the shortening of OS in patients (p < 0.05). Visual analysis showed that incomplete metabolic remission at I-PET and Eot-PET increased the risk of progress and death. In terms of predicting recurrence by I-PET, the combination of visual and semi-quantitative parameters showed higher positive predictive value (PPV) and specificity than a single index.

CONCLUSION

Three to four cycles of R-CHOP treatment may be a time point for early prediction of early recurrence/refractory (R/R) patients and active preemptive treatment. Combined visual analysis with semi-quantitative parameters of 18F-FDG PET/CT at interim can improve prognostic accuracy and may allow for more precise screening of patients requiring early intensive therapy.

NGS-determined molecular markers and disease burden metrics from ctDNA correlate with PFS in previously untreated DLBCL

Personalized risk stratification and treatment may help improve outcomes among patients with diffuse large B-cell lymphoma (DLBCL). We developed a next-generation sequencing (NGS)-based method to assess a range of potential prognostic indicators, and evaluated it using pretreatment plasma samples from 310 patients with previously untreated DLBCL from the GOYA trial (NCT01287741). Variant calls and DLBCL subtyping with the plasma-based method were concordant with corresponding tissue-based methods. Patients with a tumor burden greater than the median (p = .003) and non-germinal center B-cell-like (non-GCB) DLBCL (p = .049) had worse progression-free survival than patients with a tumor burden less than the median or GCB DLBCL. Multi-factor assessment combining orthogonal features from a single pretreatment plasma sample has promise as a prognostic indicator in this setting (p = .085). This minimally invasive plasma-based NGS assay could enable comprehensive prognostic assessment of patients in a clinical setting, with greater accessibility than current methods.

Prediction of 5-year overall survival of diffuse large B-cell lymphoma on the pola-R-CHP regimen based on 2-year event-free survival and progression-free survival

This study aimed to predict the 5-year overall survival (OS) benefit of pola-R-CHP versus R-CHOP in the POLARIX trial based on the 2-year event-free survival (EFS) and progression-free survival (PFS) rates in diffuse large B-cell lymphoma (DLBCL). We identified randomized controlled trials (RCT) published before 31 May 2023. The correlation between the logarithmic (log) hazard ratio (HR) for EFS (HREFS) or PFS (HRPFS) and the HR for OS (HROS) was estimated at the trial-level. Correlation analysis was performed between 2-year PFS or EFS and 5-year OS rates at the treatment arm-level. Linear regression models were used to calculate the 5-year OS of pola-R-CHP and R-CHOP. In the included 20 RCTs, a linear correlation between HREFS (r = 0.765) or HRPFS (r = 0.534) and HROS was observed at the trial- level. Two-year EFS (r = 0.918) or 2-year PFS (r = 0.865) correlated linearly with 5-year OS. Linear regression analysis between 2-year EFS/PFS and 5-year OS gave estimated 5-year OS rates between pola-R-CHP and R-CHOP of 6.4% and 6.3%, respectively. Two-year EFS and PFS are feasible early endpoints in patients with DLBCL treated primarily with immunochemotherapy. The pola-R-CHP regimen is expected to improve 5-year OS.

Tata Memorial Centre Evidence Based Use of Nuclear medicine diagnostic and treatment modalities in cancer

ABSTRACT

PET/CT and radioisotope therapy are diagnostic and therapeutic arms of Nuclear Medicine, respectively. With the emergence of better technology, PET/CT has become an accessible modality. Diagnostic tracers exploring disease-specific targets has led the clinicians to look beyond FDG PET. Moreover, with the emergence of theranostic pairs of radiopharmaceuticals, radioisotope therapy is gradually making it's way into treatment algorithm of common cancers in India. We therefore would like to discuss in detail the updates in PET/CT imaging and radionuclide therapy and generate a consensus-driven evidence based document which would guide the practitioners of Oncology.

A retrospective head-to-head comparison of the Lugano classification and PERCIST for FDG-PET/CT response assessment in diffuse large B-cell lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is the most common form of lymphoma. European guidelines recommend FDG-PET/CT for staging and end of treatment (EOT) response assessment, mid-treatment response assessment is optional. We compared the Lugano classification and PET Response Criteria In Solid Tumours (PERCIST) for FDG-PET/CT response assessment in DLBCL head-to-head.

METHODS

We retrospectively included patients with DLBCL who underwent first-line R-CHOP(-like) therapy (2013-2020). Interim and EOT FDG-PET/CT response were reevaluated using the Lugano classification and PERCIST. Response was dichotomized into complete metabolic response (CMR) versus non-CMR (interim and EOT) and responders versus nonresponders (interim only). The cutoff for nonresponse at interim was a Deauville score of 5 (DS5) with the Lugano classification and a partial metabolic response with ≤66% reduction in SULpeak using PERCIST (PERCIST66).

RESULTS

In multivariable Cox regression (N = 170), DS5 at interim, PERCIST66 at interim, non-CMR at EOT with the Lugano classification and non-CMR at EOT with PERCIST were predictive of progression-free survival (PFS). The Lugano classification and PERCIST agreed perfectly at interim and EOT and with 98.4% for the identification of nonresponders at interim. The accuracy for predicting events within 2 years of diagnosis was 84.2% for DS-5 at interim, 87.6% for PERCIST66 at interim, 86% for non-CMR with the Lugano classification at EOT and 83.3% for non-CMR with PERCIST at EOT.

CONCLUSION

The Lugano classification and PERCIST were equally predictive of PFS. Nonresponse at interim and non-CMR at EOT were predictive of poor PFS with comparable accuracy for predicting events within 2 years.

Outcome prediction by interim positron emission tomography and IgM monoclonal gammopathy in diffuse large B-cell lymphoma

In diffuse large B-cell lymphoma (DLBCL), a positive interim positron emission tomography (PET) scan predicts treatment failure, but the proportion of high-risk patients thus identified is small. To improve prediction, we combined the interim PET result with the presence or absence of an associated IgM gammopathy. Of 108 DLBCL patients participating in a prospective trial, nine (8%) were interim PET positive and 19 (18%) had an IgM gammopathy. The monoclonal protein was not associated with distinguishing genetic features, and its light chain restriction was not always concordant with the light chain restriction of the lymphoma. The information provided by interim PET and IgM gammopathy was combined to dichotomize the population into sizeable high-risk (1-2 adverse factors) and low-risk groups (no adverse factor) with widely different outcomes (population size, 25% vs. 75%; 3-year risk of progression, 51% vs. 10%; 3-year overall survival, 64% vs. 95%). Multivariable analyses including established risk factors revealed the interim PET result and the IgM gammopathy status to be the only factors significantly associated with outcome. Information about interim PET response and IgM gammopathy may be useful in studies testing risk-adapted treatment strategies.

Consolidative Autotransplantation Achieves High Cure Rates in Adverse-Risk Large B Cell Lymphoma

There remains an unmet need to optimize the first-line treatment of patients with high-risk large B cell lymphoma (LBCL), particularly those with a high International Prognostic Index (IPI) score or a positive interim positron emission tomography (PET) scan who experience poor outcomes with R-CHOP. This study was conducted to evaluate the real-world effectiveness of consolidative autologous stem cell transplantation (ASCT) among patients with high-risk LBCL. This retrospective study included consecutive patients with LBCL and IPI score 4 or 5 who underwent consolidative ASCT as part of first-line therapy in Alberta, Canada. Progression-free survival (PFS), overall survival (OS), and disease-specific survival (DSS) were determined using the Kaplan-Meier method. The study cohort comprised 114 patients with median age of 60 years (range, 18 to 73 years), of whom 81 (71%) had an IPI score of 4 and 33 (29%) had an IPI score of 5. With a median follow-up of 5.6 years, the 5-year PFS was 72% (95% confidence interval [CI], 62% to 79%), 5-year OS was 74% (95% CI, 64% to 81%), and 5-year DSS was 80% (95% CI, 71% to 87%). There was no significant difference in PFS among patients with and patients without positive interim PET scans (n = 24), MYC and BCL2 and/or BCL6 rearrangements (n = 26), or central nervous system involvement (n = 15). Consolidative ASCT is associated with high cure rates and favorable survival outcomes in patients with high-risk LBCL and may overcome the adverse prognostic impact of a positive interim PET scan.

Measurable Residual Disease Monitoring in Lymphoma

PURPOSE OF REVIEW

The utility of analyzing circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and disease in the bone marrow as an adjunctive tool in caring for hematologic cancer patients is expanding. This holds true for lymphoma where these biomarkers are being explored as a means of genotyping and quantifying disease. Regarding the latter, they can be used to monitor measurable residual disease (MRD) during and after treatment. This holds potential for aiding clinical decisions amidst treatment, detecting earlier relapse, and improving prognostication. Here, we review the evidence to support these applications in a variety of lymphoma subtypes.

RECENT FINDINGS

Numerous clinical trials across a variety of lymphomas have demonstrated value in MRD monitoring. MRD monitoring is often prognostic for progression free survival (PFS) and even overall survival (OS) at several time points in a disease course, particularly when utilizing serial measurements. With regards to tailoring treatment, there are a growing number of trials examining MRD-adaptive treatment strategies to intensify or de-escalate treatment to individualize care. Lastly, MRD monitoring has been utilized successfully in detecting earlier relapse when compared to more standard methods of clinical surveillance such as radiographic assessment. Although not routinely implemented into clinical practice, MRD monitoring in lymphoma is helping shape the future landscape of this disease by aiding in prognostication, guiding therapy, and detecting earlier relapse. Steps to standardize and further examine this technology prospectively are being taken to bring MRD monitoring to the forefront of the field.

Integration of PET in DLBCL

F-fluorodeoxyglucose positron emission tomography-computerized tomography (18FDG-PET/CT) is the gold-standard imaging modality for staging and response assessment for most lymphomas. This review focuses on the utility of 18FDG-PET/CT, and its role in staging, prognostication and response assessment in diffuse large B-cell lymphoma (DLBCL), including emerging possibilities for future use.

Validation of the ΔSUVmax for Interim PET Interpretation in Diffuse Large B-Cell Lymphoma on the Basis of the GAINED Clinical Trial

The GAINED phase 3 trial (ClinicalTrials.gov identifier: NCT01659099) evaluated a PET-driven consolidative strategy in patients with diffuse large B-cell lymphoma. In this post hoc analysis, we aimed to compare the prognostic value of the per-protocol PET interpretation criteria (Menton 2011 consensus) with the change in the SUVmax (ΔSUVmax) alone. Methods: Real-time central review of 18F-FDG PET/CT was performed in 581 patients after 2 cycles (PET2) and 4 cycles (PET4) of immunochemotherapy using the Menton 2011 criteria, combining the ΔSUVmax (cutoffs of 66% and 70% at PET2 and PET4, respectively) and the Deauville scale. In "special cases," when the baseline SUVmax was less than 10.0 or the interim residual tumor SUVmax was greater than 5.0, the Menton 2011 experts' consensus agreed that the ΔSUVmax may not be reliable and that the Deauville score is preferable. Prognostic values of Menton 2011 and ΔSUVmax were evaluated by Kaplan-Meier analyses in terms of progression-free survival (PFS). Results: Seventeen percent of patients at PET2 (100/581) and 8% at PET4 (49/581) had PET-negative results by ΔSUVmax but were considered to have PET-positive results according to Menton 2011 with residual SUVmax of greater than 5.0. For the population with PET2-positive results, 2-y PFS was 70% (range, 58%-80%) with ΔSUVmax alone, whereas the outcome tended to be better for those who were considered to have PET-positive results by Menton 2011, 81% (range, 72%-87%). Conversely, all 10 patients with baseline SUVmax of less than 10.0 had PET2-positive results by ΔSUVmax but were considered to have PET2-negative results by Menton 2011. These patients had the same 2-y PFS as patients with PET2-negative/PET4-negative results, indicating that the ΔSUVmax yielded false-positive results in this situation. Conclusion: We recommend the use of the ΔSUVmax alone rather than the Menton 2011 criteria for assessing the interim metabolic response in patients with diffuse large B-cell lymphoma, except when the baseline SUVmax is less than 10.0.

Exploring the cell-free total RNA transcriptome in diffuse large B-cell lymphoma and primary mediastinal B-cell lymphoma patients as biomarker source in blood plasma liquid biopsies

Introduction

Diffuse large B-cell lymphoma (DLBCL) and primary mediastinal B-cell lymphoma (PMBCL) are aggressive histological subtypes of non-Hodgkin's lymphoma. Improved understanding of the underlying molecular pathogenesis has led to new classification and risk stratification tools, including the development of cell-free biomarkers through liquid biopsies. The goal of this study was to investigate cell-free RNA (cfRNA) biomarkers in DLBCL and PMBCL patients.

Materials and methods

Blood plasma samples (n=168) and matched diagnostic formalin-fixed paraffin-embedded (FFPE) tissue samples (n=69) of DLBCL patients, PMBCL patients and healthy controls were collected between 2016-2021. Plasma samples were collected at diagnosis, at interim evaluation, after treatment, and in case of refractory or relapsed disease. RNA was extracted from 200 µl plasma using the miRNeasy serum/plasma kit and from FFPE tissue using the miRNeasy FFPE kit. RNA was subsequently sequenced on a NovaSeq 6000 instrument using the SMARTer Stranded Total RNA-seq pico v3 library preparation kit.

Results

Higher cfRNA concentrations were demonstrated in lymphoma patients compared to healthy controls. A large number of differentially abundant genes were identified between the cell-free transcriptomes of DLBCL patients, PMBCL patients, and healthy controls. Overlap analyses with matched FFPE samples showed that blood plasma has a unique transcriptomic profile that significantly differs from that of the tumor tissue. As a good concordance between tissue-derived gene expression and the immunohistochemistry Hans algorithm for cell-of-origin (COO) classification was demonstrated in the FFPE samples, but not in the plasma samples, a 64-gene cfRNA classifier was developed that can accurately determine COO in plasma. High plasma levels of a 9-gene signature (BECN1, PRKCB, COPA, TSC22D3, MAP2K3, UQCRHL, PTMAP4, EHD1, NAP1L1 pseudogene) and a 5-gene signature (FTH1P7, PTMAP4, ATF4, FTH1P8, ARMC7) were significantly associated with inferior progression-free and overall survival in DLBCL patients, respectively, independent of the NCCN-IPI score.

Conclusion

Total RNA sequencing of blood plasma samples allows the analysis of the cell-free transcriptome in DLBCL and PMBCL patients and demonstrates its unexplored potential in identifying diagnostic, cell-of-origin, and prognostic cfRNA biomarkers.

Serum Paraprotein Is Associated with Adverse Prognostic Factors and Outcome, across Different Subtypes of Mature B-Cell Malignancies-A Systematic Review

The presence of a serum paraprotein (PP) is usually associated with plasma-cell dyscrasias, Waldenstrom Macroglobulinemia/lymphoplasmacytic lymphoma, and cryoglobulinemia. However, PP is also often reported in other high- and low-grade B-cell malignancies. As these reports are sparse and heterogeneous, an overall view on this topic is lacking, Therefore, we carried out a complete literature review to detail the characteristics, and highlight differences and similarities among lymphoma entities associated with PP. In these settings, IgM and IgG are the prevalent PP subtypes, and their serum concentration is often low or even undetectable without immunofixation. The relevance of paraproteinemia and its prevalence, as well as the impact of IgG vs. IgM PP, seems to differ within B-NHL subtypes and CLL. Nonetheless, paraproteinemia is almost always associated with advanced disease, as well as with immunophenotypic, genetic, and clinical features, impacting prognosis. In fact, PP is reported as an independent prognostic marker of poor outcome. All the above call for implementing clinical practice, with the assessment of paraproteinemia, in patients' work-up. Indeed, more studies are needed to shed light on the biological mechanism causing more aggressive disease. Furthermore, the significance of paraproteinemia, in the era of targeted therapies, should be assessed in prospective trials.

SEOM-GOTEL clinical guidelines on diffuse large B cell lymphoma (2022)

Diffuse large B-cell lymphoma is the most frequent histological subtype of NHL and the paradigm for the management of aggressive lymphoma. An excisional or incisional lymph node biopsy evaluated by an experienced hemopathologist is recommended to establish the diagnosis. Twenty years following its introduction, R-CHOP remains the standard first-line treatment. No modification of this scheme (increased chemotherapy dose intensity, new monoclonal antibodies, or the addition of immunomodulators or anti-target agents) has significatively improved the clinical outcomes, whereas therapy for recurrence or progression is evolving rapidly. The irruption of CART cells, polatuzumab vedotin, tafasitamab, and CD20/CD3 bispecific antibodies are changing the natural history of relapsed patients and will challenge R-CHOP as the benchmark for newly diagnosed patients.

Development and validation of a survival nomogram in patients with primary testicular diffuse large B-cell lymphoma

OBJECTIVE

We developed and validated a nomogram for overall survival (OS) and cancer-specific survival (CSS) prediction in patients with primary testicular diffuse large B-cell lymphoma (PT-DLBCL).

METHODS

Patients diagnosed with PT-DLBCL were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Independent prognostic factors were analyzed to establish a nomogram of OS and CSS. Patients were reclassified into high- and low-risk groups; survival was compared using Kaplan-Meier curves and log-rank tests.

RESULTS

We collected 1099 PT-DLBCL cases (2000-2019) from SEER and randomized into training (n = 771) and validation (n = 328) cohorts. In univariate and multivariate Cox regression analyses, five prognostic indicators (age, treatment modality, diagnosis year, Ann Arbor stage, laterality) were used to establish a nomogram of OS and CSS. The nomogram demonstrated excellent discrimination and calibration, with concordance indices in the training and validation cohorts of 0.702 (95% confidence interval [CI], 0.677-0.727) and 0.705 (95% CI 0.67-0.74) for OS and 0.694 (95% CI 0.663-0.725) and 0.680 (95% CI 0.63-0.72) for CSS. The calibration curve and ROC analysis indicated good predictive capability of the nomogram.

CONCLUSIONS

The constructed prognostic model showed good predictive value for PT-DLBCL to assist clinicians in developing individualized treatment strategies.

Molecularly Stratified Treatment Options in Primary Refractory DLBCL/HGBL with MYC and BCL2 or BCL6 Rearrangements (HGBL, NOS with MYC/BCL6)

BACKGROUND

There is growing evidence supporting multidisciplinary molecular tumor boards (MTB) in solid tumors whereas hematologic malignancies remain underrepresented in this regard.

OBJECTIVE

The present study aimed to assess the clinical relevance of MTBs in primary refractory diffuse large B-cell lymphomas/high-grade B-cell lymphomas with MYC and BCL2 rearrangements (prDLBCL/HGBL-MYC/BCL2) (n = 13) and HGBL, not otherwise specified (NOS), with MYC and BCL6 rearrangements (prHGBL, NOS-MYC/BCL6) (n = 6) based on our previously published whole-exome sequencing (WES) cohort.

PATIENTS AND METHODS

For genomic analysis, the institutional MTB WES pipeline (University Cancer Center Schleswig-Holstein: UCCSH), certified for routine clinical diagnostics, was employed and supplemented by a comprehensive immunohistochemical work-up. Consecutive database research and annotation according to established evidence levels for molecularly stratified therapies was performed (NCT-DKTK/ESCAT).

RESULTS

Molecularly tailored treatment options with NCT-DKTK evidence level of at least m2A were identified in each case. We classified mutations in accordance with biomarker/treatment baskets and detected a heterogeneous spectrum of targetable alterations affecting immune evasion (IE; n = 30), B-cell targets (BCT; n = 26), DNA damage repair (DDR; n = 20), tyrosine kinases (TK; n = 13), cell cycle (CC; n = 7), PI3K-MTOR-AKT pathway (PAM; n = 2), RAF-MEK-ERK cascade (RME; n = 1), and others (OTH; n = 11).

CONCLUSION

Our virtual MTB approach identified potential molecularly targeted treatment options alongside targetable genomic signatures for both prDLBCL/HGBL-MYC/BCL2 and prHGBL, NOS-MYC/BCL6. These results underline the potential of MTB consultations in difficult-to-treat lymphomas early in the treatment sequence.

Quantitative PET-based biomarkers in lymphoma: getting ready for primetime

The use of functional quantitative biomarkers extracted from routine PET-CT scans to characterize clinical responses in patients with lymphoma is gaining increased attention, and these biomarkers can outperform established clinical risk factors. Total metabolic tumour volume enables individualized estimation of survival outcomes in patients with lymphoma and has shown the potential to predict response to therapy suitable for  risk-adapted treatment approaches in clinical trials. The deployment of machine learning tools in molecular imaging research can assist in recognizing complex patterns and, with image classification, in tumour identification and segmentation of data from PET-CT scans. Initial studies using fully automated approaches to calculate metabolic tumour volume and other PET-based biomarkers have demonstrated appropriate correlation with calculations from experts, warranting further testing in large-scale studies. The extraction of computer-based quantitative tumour characterization through radiomics can provide a comprehensive view of phenotypic heterogeneity that better captures the molecular and functional features of the disease. Additionally, radiomics can be integrated with genomic data to provide more accurate prognostic information. Further improvements in PET-based biomarkers are imminent, although their incorporation into clinical decision-making currently has methodological shortcomings that need to be addressed with confirmatory prospective validation in selected patient populations. In this Review, we discuss the current knowledge, challenges and opportunities in the integration of quantitative PET-based biomarkers in clinical trials and the routine management of patients with lymphoma.

An artificial intelligence method using FDG PET to predict treatment outcome in diffuse large B cell lymphoma patients

Convolutional neural networks (CNNs) may improve response prediction in diffuse large B-cell lymphoma (DLBCL). The aim of this study was to investigate the feasibility of a CNN using maximum intensity projection (MIP) images from 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) baseline scans to predict the probability of time-to-progression (TTP) within 2 years and compare it with the International Prognostic Index (IPI), i.e. a clinically used score. 296 DLBCL 18F-FDG PET/CT baseline scans collected from a prospective clinical trial (HOVON-84) were analysed. Cross-validation was performed using coronal and sagittal MIPs. An external dataset (340 DLBCL patients) was used to validate the model. Association between the probabilities, metabolic tumour volume and Dmaxbulk was assessed. Probabilities for PET scans with synthetically removed tumors were also assessed. The CNN provided a 2-year TTP prediction with an area under the curve (AUC) of 0.74, outperforming the IPI-based model (AUC = 0.68). Furthermore, high probabilities (> 0.6) of the original MIPs were considerably decreased after removing the tumours (< 0.4, generally). These findings suggest that MIP-based CNNs are able to predict treatment outcome in DLBCL.

Positron emission tomography-adapted therapy in low-risk diffuse large B-cell lymphoma: results of a randomized, phase III, non-inferiority trial

BACKGROUND

The current standard of care for non-bulky diffuse large B-cell lymphoma (DLBCL) patients with an International Prognostic Index (IPI) of 0 is four cycles of rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) but whether the same efficacy can be achieved with reduced chemotherapy regimen of four cycles for non-bulky DLBCL patients with an IPI of 1 remains unclear. This study compared four cycles versus six cycles of chemotherapy in non-bulky low-risk DLBCL patients with negative interim positron emission tomography with computed tomography (PET-CT, Deauville 1-3), irrespective of age and other IPI risk factors (IPI 0-1).

METHODS

This was an open-label, randomized, phase III, non-inferiority trial. Patients aged 14-75 years with newly diagnosed low-risk DLBCL, according to IPI, achieving PET-CT confirmed complete response (CR) after four cycles of R-CHOP were randomized (1:1) between four cycles of rituximab (4R-CHOP+4R arm) or two cycles of R-CHOP plus two cycles of rituximab (6R-CHOP+2R arm). The primary endpoint was 2-year progression-free survival (PFS), conducted in the intention-to-treat population. Safety was assessed in patients with at least one cycle of assigned treatment. The non-inferiority margin was -8%.

RESULTS

A total of 287 patients were included in the intention-to-treat analysis, the median follow-up was 47.3 months, and the 2-year PFS rate was 95% (95% confidence interval [CI], 92% to 99%) and 94% (95% CI, 91% to 98%) for the 4R-CHOP+4R and 6R-CHOP+2R arm. The absolute difference in 2-year PFS between the two arms was 1% (95% CI, -5% to 7%), supporting the non-inferiority of 4R-CHOP+4R. Grade 3-4 neutropenia was lower in the last four cycles of rituximab alone in the 4R-CHOP+4R arm (16.7% versus 76.9%), with decreased risk of febrile neutropenia (0.0% versus 8.4%) and infection (2.1% versus 14.0%).

CONCLUSIONS

For newly diagnosed low-risk DLBCL patients, interim PET-CT after four cycles of R-CHOP was effective in identifying patients with Deauville 1-3 who would have a good response and Deauville 4-5 patients who might have high-risk biological features or develop resistance. Reducing the standard six cycles to four cycles of chemotherapy had comparable clinical efficacy and fewer adverse events in low-risk, non-bulky DLBCL with interim PET-CT confirmed CR.

Cell-free DNA in large B-cell lymphoma: MRD and beyond

Large B-cell lymphomas (LBCLs) are a strikingly diverse set of diseases, including clinical, biological, and molecular heterogeneity. Despite a wealth of information resolving this heterogeneity in the research setting, applying molecular features routinely in the clinic remains challenging. The advent of circulating tumor DNA (ctDNA) liquid biopsies promises to unlock additional molecular information in the clinic, including mutational genotyping, molecular classification, and minimal residual disease detection. Here, we examine the technologies, applications, and studies exploring the utility of ctDNA in LBCLs.

[18F]FDG-PET-Based Personalized Radiotherapy Dose Prescription

PET imaging with 2'-deoxy-2'-[18F]fluoro-D-glucose ([18F]FDG) has become one of the pillars in the management of malignant diseases. It has proven value in diagnostic workup, treatment policy, follow-up, and as prognosticator for outcome. [18F]FDG is widely available and standards have been developed for PET acquisition protocols and quantitative analyses. More recently, [18F]FDG-PET is also starting to be appreciated as a decision aid for treatment personalization. This review focuses on the potential of [18F]FDG-PET for individualized radiotherapy dose prescription. This includes dose painting, gradient dose prescription, and [18F]FDG-PET guided response-adapted dose prescription. The current status, progress, and future expectations of these developments for various tumor types are discussed.

PET/CT in Non-Hodgkin Lymphoma: An Update

Non-Hodgkin lymphomas represents a heterogeneous group of lymphoproliferative disorders characterized by different clinical courses, varying from indolent to highly aggressive. ¹⁸F-FDG-PET/CT is the current state-of-the-art diagnostic imaging, for the staging, restaging and evaluation of response to treatment in lymphomas with avidity for ¹⁸F-FDG, despite it is not routinely recommended for surveillance. PET-based response criteria (using five-point Deauville Score) are nowadays uniformly applied in FDG-avid lymphomas. In this review, a comprehensive overview of the role of ¹⁸F-FDG-PET in Non-Hodgkin lymphomas is provided, at each relevant point of patient management, particularly focusing on recent advances on diffuse large B-cell lymphoma and follicular lymphoma, with brief updates also on other histotypes (such as marginal zone, mantle cell, primary mediastinal- B cell lymphoma and T cell lymphoma). PET-derived semiquantitative factors useful for patient stratification and prognostication and emerging radiomics research are also presented.

Interim FDG-PET/CT for Response Assessment of Lymphoma

The clinical use and prognostic value of interim FDG-PET/CT (iPET/CT), which is performed after treatment initiation but prior to its completion, varies by lymphoma subtype. Evidence supporting the prognostic value of iPET/CT is more robust for classical Hodgkin lymphoma (cHL), and in this lymphoma subtype, response-adapted treatment approaches guided by iPET/CT are a widely used standard of care for first-line therapy. The data supporting use of iPET/CT among patients with non-Hodgkin lymphoma (NHL) is less well-established, but failure to achieve complete metabolic response on iPET/CT is generally considered a poor prognostic factor with likely consequences for progression free survival. This review will present the available evidence supporting use of iPET/CT in lymphoma patients, particularly as it relates to prognostication and the ability to inform response-adapted treatment strategies. The latter will be addressed through a discussion on the major iPET-response adapted clinical trials with mention of ongoing trials. Special attention will be given to cHL and a few subtypes of NHL, including diffuse large B cell lymphoma (DLBCL), follicular lymphoma (FL), and peripheral T cell lymphoma (PTCL).

Prognostic Value of 18F-FDG PET/CT in Diffuse Large B-Cell Lymphoma Treated with a Risk-Adapted Immunochemotherapy Regimen

Early identification of patients with diffuse large B-cell lymphoma (DLBCL) who are likely to experience disease recurrence or refractory disease after rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) would be useful for improving risk-adapted treatment strategies. We aimed to assess the prognostic value of 18F-FDG PET/CT parameters at baseline, interim, and end of treatment (EOT). Methods: We analyzed the prognostic impact of 18F-FDG PET/CT in 166 patients with DLBCL treated with a risk-adapted immunochemotherapy regimen. Scans were obtained at baseline, after 4 cycles of R-CHOP or 3 cycles of RR-CHOP (double dose of R) and 1 cycle of CHOP alone (interim) and 6 wk after completing therapy (EOT). Progression-free survival (PFS) and overall survival (OS) were estimated using Kaplan-Meier and the impact of clinical/PET factors assessed with Cox models. We also assessed the predictive ability of the recently proposed International Metabolic Prognostic Index (IMPI). Results: The median follow-up was 7.9 y. International Prognostic Index (IPI), baseline metabolic tumor volume (MTV), and change in maximum SUV (ΔSUVmax) at interim scans were statistically significant predictors for OS. Baseline MTV, interim ΔSUVmax, and EOT Deauville score were statistically significant predictors of PFS. Combining interim PET parameters demonstrated that patients with Deauville 4-5 and positive ΔSUVmax ≤ 70% at restaging (∼10% of the cohort) had extremely poor prognosis. The IMPI had limited discrimination and slightly overestimated the event rate in our cohort. Conclusion: Baseline MTV and interim ΔSUVmax predicted both PFS and OS with this sequential immunochemotherapy program. Combining interim Deauville score with interim ΔSUVmax may identify an extremely high-risk DLBCL population.

Is local review of positron emission tomography scans sufficient in diffuse large B-cell lymphoma clinical trials? A CALGB 50303 analysis

BACKGROUND

Quantitative methods of Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) interpretation, including the percent change in FDG uptake from baseline (ΔSUV), are under investigation in lymphoma to overcome challenges associated with visual scoring systems (VSS) such as the Deauville 5-point scale (5-PS).

METHODS

In CALGB 50303, patients with DLBCL received frontline R-CHOP or DA-EPOCH-R, and although there were no significant associations between interim PET responses assessed centrally after cycle 2 (iPET) using 5-PS with progression-free survival (PFS) or overall survival (OS), there were significant associations between central determinations of iPET ∆SUV with PFS/OS. In this patient cohort, we retrospectively compared local vs central iPET readings and evaluated associations between local imaging data and survival outcomes.

RESULTS

Agreement between local and central review was moderate (kappa = 0.53) for VSS and high (kappa = 0.81) for ∆SUV categories (<66% vs. ≥66%). ∆SUV ≥66% at iPET was significantly associated with PFS (p = 0.03) and OS (p = 0.002), but VSS was not. Associations with PFS/OS when applying local review vs central review were comparable.

CONCLUSIONS

These data suggest that local PET interpretation for response determination may be acceptable in clinical trials. Our findings also highlight limitations of VSS and call for incorporation of more objective measures of response assessment in clinical trials.

Four-dimensional quantitative analysis using FDG-PET in clinical oncology

Positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) has been commonly used in many oncological areas. High-resolution PET permits a three-dimensional analysis of FDG distributions on various lesions in vivo, which can be applied for tissue characterization, risk analysis, and treatment monitoring after chemoradiotherapy and immunotherapy. Metabolic changes can be assessed using the tumor absolute FDG uptake as standardized uptake value (SUV) and metabolic tumor volume (MTV). In addition, tumor heterogeneity assessment can potentially estimate tumor aggressiveness and resistance to chemoradiotherapy. Attempts have been made to quantify intratumoral heterogeneity using radiomics. Recent reports have indicated the clinical feasibility of a dynamic FDG PET-computed tomography (CT) in pilot cohort studies of oncological cases. Dynamic imaging permits the assessment of temporal changes in FDG uptake after administration, which is particularly useful for differentiating pathological from physiological uptakes with high diagnostic accuracy. In addition, several new parameters have been introduced for the in vivo quantitative analysis of FDG metabolic processes. Thus, a four-dimensional FDG PET-CT is available for precise tissue characterization of various lesions. This review introduces various new techniques for the quantitative analysis of FDG distribution and glucose metabolism using a four-dimensional FDG analysis with PET-CT. This elegant study reveals the important role of tissue characterization and treatment strategies in oncology.

Interim FDG18-PET SUVmax Variation Adds Prognostic Value to Deauville 5-Point Scale in the Identification of Patients with Ultra-High-Risk Diffuse Large B Cell Lymphoma

INTRODUCTION

Interim response evaluation by ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (iPET) in diffuse large B cell lymphoma (DLBCL) could be important to rule out disease progression and has been suggested to be predictive of survival. However, treatment guidance by iPET is not yet recommended for DLBCL in clinical practice. We aimed to compare the predictive value of iPET when utilizing the visual Deauville 5-point scale (DS) and the semiquantitative variation of maximum standardized uptake value (ΔSUV_max).

MATERIALS AND METHODS

We included 85 patients diagnosed with DLBCL and uniformly treated with standard protocols. iPET with DS of 1-3 and/or ΔSUV_max ≥66% was defined as negative. Univariable and multivariable Cox regression analyses were performed to determine the independent factors affecting progression free survival (PFS) or overall survival (OS) and to estimate PFS and OS.

RESULTS

iPET positivity, measured by DS or ΔSUV_max, showed predictive value of disease refractoriness, improved by combining DS and ΔSUV_max. After a median follow-up of 50.1 months, iPET was an independent predictor for both PFS and OS when interpreted by DS, but only for PFS by ΔSUV_max. Combined visual and semiquantitative analysis (D4-5 & ΔSUV_max<66%) was an independent predictor of PFS and OS, and allowed to identify an ultra-high-risk subgroup of patients with very dismal outcome, increasing the discriminating capacity for iPET.

CONCLUSION

Our study suggests that combined DS and ΔSUV_max in iPET assessment predicts refractory disease and distinguishes ultra-high-risk DLBCL patients with a very dismal prognosis, who may benefit from PET-guided therapy adjustment.

Determinants of resistance to engineered T cell therapies targeting CD19 in large B cell lymphomas

Most relapsed/refractory large B cell lymphoma (r/rLBCL) patients receiving anti-CD19 chimeric antigen receptor (CAR19) T cells relapse. To characterize determinants of resistance, we profiled over 700 longitudinal specimens from two independent cohorts (n = 65 and n = 73) of r/rLBCL patients treated with axicabtagene ciloleucel. A method for simultaneous profiling of circulating tumor DNA (ctDNA), cell-free CAR19 (cfCAR19) retroviral fragments, and cell-free T cell receptor rearrangements (cfTCR) enabled integration of tumor and both engineered and non-engineered T cell effector-mediated factors for assessing treatment failure and predicting outcomes. Alterations in multiple classes of genes are associated with resistance, including B cell identity (PAX5 and IRF8), immune checkpoints (CD274), and those affecting the microenvironment (TMEM30A). Somatic tumor alterations affect CAR19 therapy at multiple levels, including CAR19 T cell expansion, persistence, and tumor microenvironment. Further, CAR19 T cells play a reciprocal role in shaping tumor genotype and phenotype. We envision these findings will facilitate improved chimeric antigen receptor (CAR) T cells and personalized therapeutic approaches.

Primary refractory plasmablastic lymphoma: A precision oncology approach

Introduction

Hematologic malignancies are currently underrepresented in multidisciplinary molecular-tumor-boards (MTB). This study assesses the potential of precision-oncology in primary-refractory plasmablastic-lymphoma (prPBL), a highly lethal blood cancer.

Methods

We evaluated clinicopathological and molecular-genetic data of 14 clinically annotated prPBL-patients from initial diagnosis. For this proof-of-concept study, we employed our certified institutional MTB-pipeline (University-Cancer-Center-Schleswig-Holstein, UCCSH) to annotate a comprehensive dataset within the scope of a virtual MTB-setting, ultimately recommending molecularly stratified therapies. Evidence-levels for MTB-recommendations were defined in accordance with the NCT/DKTK and ESCAT criteria.

Results

Median age in the cohort was 76.5 years (range 56-91), 78.6% of patients were male, 50% were HIV-positive and clinical outcome was dismal. Comprehensive genomic/transcriptomic analysis revealed potential recommendations of a molecularly stratified treatment option with evidence-levels according to NCT/DKTK of at least m2B/ESCAT of at least IIIA were detected for all 14 prPBL-cases. In addition, immunohistochemical-assessment (CD19/CD30/CD38/CD79B) revealed targeted treatment-recommendations in all 14 cases. Genetic alterations were classified by treatment-baskets proposed by Horak et al. Hereby, we identified tyrosine-kinases (TK; n=4), PI3K-MTOR-AKT-pathway (PAM; n=3), cell-cycle-alterations (CC; n=2), RAF-MEK-ERK-cascade (RME; n=2), immune-evasion (IE; n=2), B-cell-targets (BCT; n=25) and others (OTH; n=4) for targeted treatment-recommendations. The minimum requirement for consideration of a drug within the scope of the study was FDA-fast-track development.

Discussion

The presented proof-of-concept study demonstrates the clinical potential of precision-oncology, even in prPBL-patients. Due to the aggressive course of the disease, there is an urgent medical-need for personalized treatment approaches, and this population should be considered for MTB inclusion at the earliest time.

Diffuse Large B-Cell Lymphoma (DLBCL): Early Patient Management and Emerging Treatment Options

Diffuse large B-cell lymphoma (DLBCL) represents a curable disease with a 60-70% chance of cure with current R-CHOP chemoimmunotherapy. However, 30-40% of patients are refractory or relapsing. Many attempts failed to improve the outcome of DLBCL patients, including the intensification of R-CHOP regimen, consolidation, or maintenance therapy since the introduction of R-CHOP in 2000. Better understanding of both molecular biology of lymphoma cells and the tumor microenvironment raised the hope for future improvement of DLBCL patients' survival. Novel molecular findings have initiated clinical trials exploring targeted therapy based on driver genetic alterations with an intent to improve survival of high-risk subsets of patients. But the preliminary results remain ambiguous. The approach "agnostic" to specific molecular alterations of lymphoma cell includes antibody-drug conjugates (especially polatuzumab vedotin), immunotherapy comprising different antibodies with immunomodulatory effect (tafasitamab, lenalidomide), and T-cell engaging therapy (bispecific antibodies, early use of CAR T-cell). This approach could increase the cure rates and change the current therapeutic paradigm. However, better prognostic stratification, smarter designs of clinical trials, modification of endpoints including the use of ctDNA are needed. This review covers the complexity of DLBCL management.

Interim FDG-PET analysis to identify patients with aggressive non-Hodgkin lymphoma who benefit from treatment intensification: a post-hoc analysis of the PETAL trial

The randomized PETAL trial failed to demonstrate a benefit of interim FDG-PET (iPET)-based treatment intensification over continued standard therapy with CHOP (plus rituximab (R) in CD20-positive lymphomas). We hypothesized that PET analysis of all lymphoma manifestations may identify patients who benefitted from treatment intensification. A previously developed neural network was employed for iPET analysis to identify the highest pathological FDG uptake (max-SUVAI) and the mean FDG uptake of all lymphoma manifestations (mean-SUVAI). High mean-SUVAI uptake was determined separately for iPET-positive and iPET-negative patients. The endpoint was time-to-progression (TTP). There was a significant interaction of additional rituximab and mean-SUVAI in the iPET-negative group (HR = 0.6, p < 0.05). Patients with high mean-SUVAI had significantly prolonged TTP when treated with 6xR-CHOP + 2 R (not reached versus 52 months, p < 0.05), whereas max-SUVmanual failed to show an impact of additional rituximab. In the iPET-positive group, patients with high mean-SUVAI had a significantly longer TTP with (R-)CHOP than with the Burkitt protocol (14 versus 4 months, p < 0.01). Comprehensive iPET evaluation may provide new prognosticators in aggressive lymphoma. Additional application of rituximab was associated with prolonged TTP in iPET-negative patients with high mean-SUVAI. Comprehensive iPET interpretation could identify high-risk patients who benefit from study-specific interventions.

PET-CT in Clinical Adult Oncology: I. Hematologic Malignancies

PET-CT is an advanced imaging modality with many oncologic applications, including staging, assessment of response to therapy, restaging and evaluation of suspected recurrence. The goal of this 6-part series of review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for the more common adult malignancies. In the first article of this series, hematologic malignancies are addressed. The classification of these malignancies will be outlined, with the disclaimer that the classification of lymphomas is constantly evolving. Critical applications, potential pitfalls, and nuances of PET-CT imaging in hematologic malignancies and imaging features of the major categories of these tumors are addressed. Issues of clinical importance that must be reported by the imaging professionals are outlined. The focus of this article is on [¹⁸F] fluorodeoxyglucose (FDG), rather that research tracers or those requiring a local cyclotron. This information will serve as a resource for the appropriate role and limitations of PET-CT in the clinical management of patients with hematological malignancy for health care professionals caring for adult patients with hematologic malignancies. It also serves as a practical guide for imaging providers, including radiologists, nuclear medicine physicians and their trainees.

Baseline radiomics features and MYC rearrangement status predict progression in aggressive B-cell lymphoma

We investigated whether the outcome prediction of patients with aggressive B-cell lymphoma can be improved by combining clinical, molecular genotype, and radiomics features. MYC, BCL2, and BCL6 rearrangements were assessed using fluorescence in situ hybridization. Seventeen radiomics features were extracted from the baseline positron emission tomography-computed tomography of 323 patients, which included maximum standardized uptake value (SUVmax), SUVpeak, SUVmean, metabolic tumor volume (MTV), total lesion glycolysis, and 12 dissemination features pertaining to distance, differences in uptake and volume between lesions, respectively. Logistic regression with backward feature selection was used to predict progression after 2 years. The predictive value of (1) International Prognostic Index (IPI); (2) IPI plus MYC; (3) IPI, MYC, and MTV; (4) radiomics; and (5) MYC plus radiomics models were tested using the cross-validated area under the curve (CV-AUC) and positive predictive values (PPVs). IPI yielded a CV-AUC of 0.65 ± 0.07 with a PPV of 29.6%. The IPI plus MYC model yielded a CV-AUC of 0.68 ± 0.08. IPI, MYC, and MTV yielded a CV-AUC of 0.74 ± 0.08. The highest model performance of the radiomics model was observed for MTV combined with the maximum distance between the largest lesion and another lesion, the maximum difference in SUVpeak between 2 lesions, and the sum of distances between all lesions, yielding an improved CV-AUC of 0.77 ± 0.07. The same radiomics features were retained when adding MYC (CV-AUC, 0.77 ± 0.07). PPV was highest for the MYC plus radiomics model (50.0%) and increased by 20% compared with the IPI (29.6%). Adding radiomics features improved model performance and PPV and can, therefore, aid in identifying poor prognosis patients.

Diffuse Large B-Cell Lymphoma in Chile: The Impact of Combined CHOP Plus Rituximab in the Public Health System

PURPOSE

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype. The purpose of this study was to evaluate the clinical features, prognostic factors, and results of DLBCL that was treated in the cancer centers of the public health system in Chile and compare cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) with rituximab with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP).

PATIENTS AND METHODS

Patients age > 15 years who were treated in 18 cancer centers in the country between 2001 and 2017 were included. The Kaplan-Meier method was used to calculate overall survival (OS), and Cox proportional hazard regression modeling was used to evaluate the effect of the addition of rituximab to CHOP on OS.

RESULTS

A total of 1,807 patients were evaluated. The median age at diagnosis was 62 (range, 15-95) years, with a female predominance (53%). Half of the patients were age ≥ 60 years. Serology for HIV infection was positive in 5% of cases (96 cases). International Prognostic Index scores were available for 90% of patients, of which 45% had low-risk, 25% low-intermediate-risk, 18% high-intermediate-risk, and 11% high-risk scores. CHOP was administered to 986 patients (55%; median follow-up, 13.2 years) and R-CHOP to 821 patients (45%; median follow-up, 8.4 years). R-CHOP was associated with superior OS compared with CHOP (5-year 66% v 48%, and 10-year 53% v 35%; P < .001).

CONCLUSION

Rituximab improved the survival of patients with DLBCL diagnosed and treated in Chile. The benefit was sustained over time, with curative rates of > 50%. This intervention shows that the inclusion of this biological drug justified the expenses incurred by the Ministry of Health in the National Lymphoma Protocols in Chile.

The role of 18F-FDG PET/CT in patients with diffuse large B-cell lymphoma after radioimmunotherapy using 131I-rituximab as consolidation therapy

Purpose

To evaluate the prognostic value of pretreatment ¹⁸F-FDG PET/CT after consolidation therapy of ¹³¹I-rituximab in patients with diffuse large B-cell lymphoma (DLBCL) who had acquired complete remission after receiving chemotherapy.

Methods

Patients who were diagnosed with DLBCL via histologic confirmation were retrospectively reviewed. All patients had achieved complete remission after 6 to 8 cycles of R-CHOP (rituximab, cyclophosphamide, vincristine, doxorubicin, and prednisolone) chemotherapy after which they underwent consolidation treatment with ¹³¹I-rituximab. ¹⁸F-FDG PET/CT scans were performed before R-CHOP for initial staging. The largest diameter of tumor, maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were obtained from pretreatment ¹⁸F-FDG PET/CT scans. Receiver-operating characteristic curves analysis was introduced for assessing the optimal criteria. Kaplan-Meier curve survival analysis was performed to evaluate both relapse free survival (RFS) and overall survival (OS).

Results

A total of 15 patients (12 males and 3 females) with a mean age of 56 (range, 30–73) years were enrolled. The median follow-up period of these patients was 73 months (range, 11–108 months). Four (27%) patients relapsed. Of them, three died during follow-up. Median values of the largest tumor size, highest SUVmax, MTV, and TLG were 5.3 cm (range, 2.0–16.4 cm), 20.2 (range, 11.1–67.4), 231.51 (range, 15–38.34), and 1277.95 (range, 238.37–10341.04), respectively. Patients with SUVmax less than or equal to 16.9 showed significantly worse RFS than patients with SUVmax greater than 16.9 (5-year RFS rate: 60% vs. 100%, p = 0.008). Patients with SUVmax less than or equal to 16.9 showed significantly worse OS than patients with SUVmax greater than 16.9 (5-year OS rate: 80% vs. 100% p = 0.042).

Conclusion

Higher SUVmax at pretreatment ¹⁸F-FDG PET/CT was associated with better relapse free survival and overall survival in DLBCL patients after consolidation therapy with ¹³¹I-rituximab. However, because this study has a small number of patients, a phase 3 study with a larger number of patients is needed for clinical application in the future.

A tumor volume and performance status model to predict outcome before treatment in diffuse large B-cell lymphoma

Aggressive large B-cell lymphoma (LBCL) has variable outcomes. Current prognostic tools use factors for risk stratification that inadequately identify patients at high risk of refractory disease or relapse before initial treatment. A model associating 2 risk factors, total metabolic tumor volume (TMTV) >220 cm3 (determined by fluorine-18 fluorodeoxyglucose positron emission tomography coupled with computed tomography) and performance status (PS) ≥2, identified as prognostic in 301 older patients in the REMARC trial (#NCT01122472), was validated in 2174 patients of all ages treated in 2 clinical trials, PETAL (Positron Emission Tomography-Guided Therapy of Aggressive Non-Hodgkin Lymphomas; N = 510) and GOYA (N = 1315), and in real-world clinics (N = 349) across Europe and the United States. Three risk categories, low (no factors), intermediate (1 risk factor), and high (2 risk factors), significantly discriminated outcome in most of the series. Patients with 2 risk factors had worse outcomes than patients with no risk factors in the PETAL, GOYA, and real-world series. Patients with intermediate risk also had significantly worse outcomes than patients with no risk factors. The TMTV/Eastern Cooperative Oncology Group-PS combination outperformed the International Prognostic Index with a positive C-index for progression-free survival and overall survival in most series. The combination of high TMTV > 220 cm3 and ECOG-PS ≥ 2 is a simple clinical model to identify aggressive LBCL risk categories before treatment. This combination addresses the unmet need to better predict before treatment initiation for aggressive LBCL the patients likely to benefit the most or not at all from therapy.

Circulating tumor DNA in B-cell lymphoma: technical advances, clinical applications, and perspectives for translational research

Noninvasive disease monitoring and risk stratification by circulating tumor DNA (ctDNA) profiling has become a potential novel strategy for patient management in B-cell lymphoma. Emerging innovative therapeutic options and an unprecedented growth in our understanding of biological and molecular factors underlying lymphoma heterogeneity have fundamentally increased the need for precision-based tools facilitating personalized and accurate disease profiling and quantification. By capturing the entire mutational landscape of tumors, ctDNA assessment has some decisive advantages over conventional tissue biopsies, which usually target only one single tumor site. Due to its non- or minimal-invasive nature, serial and repeated ctDNA profiling provides a real-time picture of the genetic composition and facilitates quantification of tumor burden any time during the course of the disease. In this review, we present a comprehensive overview of technologies used for ctDNA detection and genotyping in B-cell lymphoma, focusing on pre-analytical and technical requirements, the advantages and limitations of various approaches, and highlight recent advances around improving sensitivity and suppressing technical errors. We broadly review potential applications of ctDNA in clinical practice and for translational research by describing how ctDNA might enhance lymphoma subtype classification, treatment response assessment, outcome prediction, and monitoring of measurable residual disease. We finally discuss how ctDNA could be implemented in prospective clinical trials as a novel surrogate endpoint and be utilized as a decision-making tool to guide lymphoma treatment in the future.

The value of FDG PET/CT imaging in outcome prediction and response assessment of lymphoma patients treated with immunotherapy: a meta-analysis and systematic review

PURPOSE

Treatment strategies of lymphoid malignancies have been revolutionized by immunotherapy. Because of the inherent property of Hodgkin lymphoma and some subtypes of non-Hodgkin lymphoma as a highly FDG-avid tumor, functional ¹⁸F-FDG PET/CT imaging is already embedded in their routine care. Nevertheless, the question is whether it is still valuable in the context of these tumors being treated with immunotherapy. Herein, we will review the value of ¹⁸F-FDG PET/CT imaging lymphoid tumors treated with immunotherapy regimens.

METHODS

A comprehensive literature search of the PubMed database was conducted on the value of the ¹⁸F-FDG PET/CT for immunotherapy response monitoring of patients with malignant lymphoma. The articles were considered eligible if they met all of the following inclusion criteria: (a) clinical studies on patients with different types of malignant lymphoma, (b) treatment with anti-CD20 antibodies, immune checkpoint inhibitors or immune cell therapies, (c) and incorporated PET/CT with ¹⁸F-FDG as the PET tracer.

RESULTS

From the initial 1488 papers identified, 91 were ultimately included in our study. In anti-CD20 therapy, the highest pooled hazard ratios (HRs) of baseline, early, and late response monitoring parameters for progression-free survival (PFS) belong to metabolic tumor volume (MTV) (3.19 (95%CI: 2.36-4.30)), maximum standardized uptake value (SUVmax) (3.25 (95%CI: 2.08-5.08)), and Deauville score (DS) (3.73 (95%CI: 2.50-5.56)), respectively. These measurements for overall survival (OS) were MTV (4.39 (95%CI: 2.71-7.08)), DS (3.23 (95%CI: 1.87-5.58)), and DS (3.64 (95%CI: 1.40-9.43)), respectively. Early and late ¹⁸F-FDG PET/CT response assessment in immune checkpoint inhibitors (ICI) and immune cell therapy might be an effective tool for prediction of clinical outcome.

CONCLUSION

For anti-CD20 therapy of lymphoma, the MTV as a baseline ¹⁸F-FDG PET/CT-derived parameter has the highest HRs for PFS and OS. The DS as visual criteria in early and late response assessment has higher HRs for PFS and OS compared to the international harmonization project (IHP) visual criteria in anti-CD20 therapy. Early changes in ¹⁸F-FDG PET parameters may be predictive of response to ICIs and cell therapy in lymphoma patients.

Proposed New Dynamic Prognostic Index for Diffuse Large B-Cell Lymphoma: International Metabolic Prognostic Index

PURPOSE

Baseline metabolic tumor volume (MTV) is a promising biomarker in diffuse large B-cell lymphoma (DLBCL). Our aims were to determine the best statistical relationship between MTV and survival and to compare MTV with the International Prognostic Index (IPI) and its individual components to derive the best prognostic model.

METHODS

PET scans and clinical data were included from five published studies in newly diagnosed diffuse large B-cell lymphoma. Transformations of MTV were compared with the primary end points of 3-year progression-free survival (PFS) and overall survival (OS) to derive the best relationship for further analyses. MTV was compared with IPI categories and individual components to derive the best model. Patients were grouped into three groups for survival analysis using Kaplan-Meier analysis; 10% at highest risk, 30% intermediate risk, and 60% lowest risk, corresponding with expected clinical outcome. Validation of the best model was performed using four studies as a test set and the fifth study for validation and repeated five times.

RESULTS

The best relationship for MTV and survival was a linear spline model with one knot located at the median MTV value of 307.9 cm3. MTV was a better predictor than IPI for PFS and OS. The best model combined MTV with age as continuous variables and individual stage as I-IV. The MTV-age-stage model performed better than IPI and was also better at defining a high-risk group (3-year PFS 46.3% v 58.0% and 3-year OS 51.5% v 66.4% for the new model and IPI, respectively). A regression formula was derived to estimate individual patient survival probabilities.

CONCLUSION

A new prognostic index is proposed using MTV, age, and stage, which outperforms IPI and enables individualized estimates of patient outcome.

Outcomes Among Classical Hodgkin Lymphoma Patients After an Interim PET Scan: A Real-World Experience

INTRODUCTION

The utility of dose escalation after positive positron emission tomography following 2 cycles of ABVD (PET2) for Hodgkin Lymphoma (HL) remains controversial. We describe the United States real-world practice patterns for PET2 positive patients.

PATIENTS AND METHODS

Data was collected from 15 sites on PET2 positive HL patients after receiving frontline treatment between January, 2015 and June, 2019. Descriptive analyses between those with therapy change and those continuing initial therapy were assessed.

RESULTS

A total of 129 patients were identified; 111 (86%) were treated with ABVD therapy and 18 (14%) with an alternate regimen. At PET2 assessment, 74.4% (96/129) had Deauville score (DS) 4 and 25.6% (33/129) had DS 5. Of the 66 limited stage (LS) patients with PET2 DS score of 4/5, 77.3% (51/66) continued initial therapy and 22.7% (15/66) changed to escalated therapy. The 12-month progression-free survival (PFS) for DS 4/5 LS patients was 67.0% (95% CI; 54.9-81.7) for patients without escalation compared with 51.4% (95% CI; 30.8-85.8) for those who escalated. Of the 63 DS 4/5 patients with advanced stage (AS) disease, 76.2% (48/63) continued initial therapy and 23.8% (15/63) changed to escalated therapy. The 12-month PFS for DS 4/5 AS patients was 38.3% (95% CI: 26.3%-55.7%) for patients without escalation compared with 57.1% (95% CI: 36.3-89.9) for those with escalation.

CONCLUSION

A minority of PET2 positive HL patients undergo therapy escalation and outcomes remain overall suboptimal. Improved prognostics markers and better therapeutics are required to improve outcomes for high-risk PET2 positive HL patients.

18F-FDG PET Improves Baseline Clinical Predictors of Response in Diffuse Large B-Cell Lymphoma: The HOVON-84 Study

We aimed to determine the added value of baseline metabolic tumor volume (MTV) and interim PET (I-PET) to the age-adjusted international prognostic index (aaIPI) to predict 2-y progression-free survival (PFS) in diffuse large B-cell lymphoma. Secondary objectives were to investigate optimal I-PET response criteria (using Deauville score [DS] or quantitative change in SUV_max [ΔSUV_max] between baseline and I-PET4 [observational I-PET scans after 4 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone administered in 2-wk intervals with intensified rituximab in the first 4 cycles [R(R)-CHOP14]). Methods: I-PET4 scans in the HOVON-84 (Hemato-Oncologie voor Volwassenen Nederland [Haemato Oncology Foundation for Adults in the Netherlands]) randomized clinical trial (EudraCT 2006-005174-42) were centrally reviewed using DS (cutoff, 4-5). Additionally, ΔSUV_max (prespecified cutoff, 70%) and baseline MTV were measured. Multivariable hazard ratio (HR), positive predictive value (PPV), and negative predictive value (NPV) were obtained for 2-y PFS. Results: In total, 513 I-PET4 scans were reviewed according to DS, and ΔSUV_max and baseline MTV were available for 367 and 296 patients. The NPV of I-PET ranged between 82% and 86% for all PET response criteria. Univariate HR and PPV were better for ΔSUV_max (4.8% and 53%, respectively) than for DS (3.1% and 38%, respectively). aaIPI and ΔSUV_max independently predicted 2-y PFS (HR, 3.2 and 5.0, respectively); adding MTV brought about a slight improvement. Low or low-intermediate aaIPI combined with a ΔSUV_max of more than 70% (37% of patients) yielded an NPV of 93%, and the combination of high-intermediate or high aaIPI and a ΔSUV_max of 70% or less yielded a PPV of 65%. Conclusion: In this study on diffuse large B-cell lymphoma, I-PET after 4 cycles of R(R)-CHOP14 added predictive value to aaIPI for 2-y PFS, and both were independent response biomarkers in a multivariable Cox model. We externally validated that ΔSUV_max outperformed DS in 2-y PFS prediction.

Two-Year Event-Free Survival Prediction in DLBCL Patients Based on In Vivo Radiomics and Clinical Parameters

Purpose

For the identification of high-risk patients in diffuse large B-cell lymphoma (DLBCL), we investigated the prognostic significance of in vivo radiomics derived from baseline [¹⁸F]FDG PET/CT and clinical parameters.

Methods

Pre-treatment [¹⁸F]FDG PET/CT scans of 85 patients diagnosed with DLBCL were assessed. The scans were carried out in two clinical centers. Two-year event-free survival (EFS) was defined. After delineation of lymphoma lesions, conventional PET parameters and in vivo radiomics were extracted. For 2-year EFS prognosis assessment, the Center 1 dataset was utilized as the training set and underwent automated machine learning analysis. The dataset of Center 2 was utilized as an independent test set to validate the established predictive model built by the dataset of Center 1.

Results

The automated machine learning analysis of the Center 1 dataset revealed that the most important features for building 2-year EFS are as follows: max diameter, neighbor gray tone difference matrix (NGTDM) busyness, total lesion glycolysis, total metabolic tumor volume, and NGTDM coarseness. The predictive model built on the Center 1 dataset yielded 79% sensitivity, 83% specificity, 69% positive predictive value, 89% negative predictive value, and 0.85 AUC by evaluating the Center 2 dataset.

Conclusion

Based on our dual-center retrospective analysis, predicting 2-year EFS built on imaging features is feasible by utilizing high-performance automated machine learning.