Distinct Hodgkin lymphoma subtypes defined by noninvasive genomic profiling.

The scarcity of malignant Hodgkin and Reed-Sternberg cells hampers tissue-based comprehensive genomic profiling of classic Hodgkin lymphoma (cHL). By contrast, liquid biopsies show promise for molecular profiling of cHL due to relatively high circulating tumour DNA (ctDNA) levels1-4. Here we show that the plasma representation of mutations exceeds the bulk tumour representation in most cases, making cHL particularly amenable to noninvasive profiling. Leveraging single-cell transcriptional profiles of cHL tumours, we demonstrate Hodgkin and Reed-Sternberg ctDNA shedding to be shaped by DNASE1L3, whose increased tumour microenvironment-derived expression drives high ctDNA concentrations. Using this insight, we comprehensively profile 366 patients, revealing two distinct cHL genomic subtypes with characteristic clinical and prognostic correlates, as well as distinct transcriptional and immunological profiles. Furthermore, we identify a novel class of truncating IL4R mutations that are dependent on IL-13 signalling and therapeutically targetable with IL-4Rα-blocking antibodies. Finally, using PhasED-seq5, we demonstrate the clinical value of pretreatment and on-treatment ctDNA levels for longitudinally refining cHL risk prediction and for detection of radiographically occult minimal residual disease. Collectively, these results support the utility of noninvasive strategies for genotyping and dynamic monitoring of cHL, as well as capturing molecularly distinct subtypes with diagnostic, prognostic and therapeutic potential.

Brentuximab vedotin with dacarbazine or nivolumab as frontline cHL therapy for older patients ineligible for chemotherapy.

ABSTRACT: Older patients with advanced-stage classical Hodgkin lymphoma (cHL) have inferior outcomes compared with younger patients, potentially due to comorbidities and frailty. This noncomparative phase 2 study enrolled patients aged ≥60 years with cHL unfit for conventional chemotherapy to receive frontline brentuximab vedotin (BV; 1.8 mg/kg) with dacarbazine (DTIC; 375 mg/m2) (part B) or nivolumab (part D; 3 mg/kg). In parts B and D, 50% and 38% of patients, respectively, had ≥3 general comorbidities or ≥1 significant comorbidity. Of the 22 patients treated with BV-DTIC, 95% achieved objective response, and 64% achieved complete response (CR). With a median follow-up of 63.6 months, median duration of response (mDOR) was 46.0 months. Median progression-free survival (mPFS) was 47.2 months; median overall survival (mOS) was not reached. Of 21 patients treated with BV-nivolumab, 86% achieved objective response, and 67% achieved CR. With 51.6 months of median follow-up, mDOR, mPFS, and mOS were not reached. Ten patients (45%) with BV-DTIC and 16 patients (76%) with BV-nivolumab experienced grade ≥3 treatment-emergent adverse events; sensory peripheral neuropathy (PN; 27%) and neutropenia (9%) were most common with BV-DTIC, and increased lipase (24%), motor PN (19%), and sensory PN (19%) were most common with BV-nivolumab. Despite high median age, inclusion of patients aged ≤88 years, and frailty, these results demonstrate safety and promising durable efficacy of BV-DTIC and BV-nivolumab combinations as frontline treatment, suggesting potential alternatives for older patients with cHL unfit for initial conventional chemotherapy. This trial was registered at www.clinicaltrials.gov as #NCT01716806.

The phase 2 LYSA study of prednisone, vinblastine, doxorubicin, and bendamustine for untreated Hodgkin lymphoma in older patients.

ABSTRACT: Older patients with classical Hodgkin lymphoma (cHL) require more effective and less toxic therapies than younger patients. In this multicenter, prospective, phase 2 study, we investigated a new firstline therapy regimen comprising 6 cycles of prednisone (40 mg/m2, days 1-5), vinblastine (6 mg/m2, day 1), doxorubicin (40 mg/m2, day 1), and bendamustine (120 mg/m2, day 1) (PVAB regimen) every 21 days for patients with newly diagnosed cHL aged ≥61 years with an advanced Ann Arbor stage. A Mini Nutritional Assessment score ≥17 was the cutoff value for patients aged ≥70 years. The primary end point was the complete metabolic response (CMR) rate after 6 cycles. The median age of the 89 included patients was 68 years (range, 61-88 years), with 35 patients (39%) aged ≥70 years. Seventy-eight patients (88%) completed the 6 cycles. The toxicity rate was acceptable, with a 20% rate of related serious adverse events. CMR was achieved by 69 patients (77.5%; 95% confidence interval [CI], 67-86). After a median follow-up of 42 months, 31 patients progressed or relapsed (35%), and 24 died (27%) from HL (n = 11), toxicity during treatment (n = 4), secondary cancers (n = 6), or other causes (n = 3). The 4-year progression-free survival (PFS) and overall survival rates were 50% and 69%, respectively. Multivariate analysis showed that liver involvement (P = .001), lymphopenia (P = .001), CRP (P = .0005), and comedications (P = .003) were independently associated with PFS. The PVAB regimen yielded a high CMR rate with acceptable toxicity. Over long-term follow-up, survival end points were influenced by unrelated lymphoma events. This trial was registered at www.clinicaltrials.gov as #NCT02414568 and at EudraCT as 2014-001002-17.

Epstein-Barr virus-encoded EBNA2 downregulates ICOSL by inducing miR-24 in B-cell lymphoma.

ABSTRACT: Hematological malignancies such as Burkitt lymphoma (BL), Hodgkin lymphoma (HL), and diffuse large B-cell lymphoma (DLBCL) cause significant morbidity in humans. A substantial number of these lymphomas, particularly HL and DLBCLs have poorer prognosis because of their association with Epstein-Barr virus (EBV). Our earlier studies have shown that EBV-encoded nuclear antigen (EBNA2) upregulates programmed cell death ligand 1 in DLBCL and BLs by downregulating microRNA-34a. Here, we investigated whether EBNA2 affects the inducible costimulator (ICOS) ligand (ICOSL), a molecule required for efficient recognition of tumor cells by T cells through the engagement of ICOS on the latter. In virus-infected and EBNA2-transfected B-lymphoma cells, ICOSL expression was reduced. Our investigation of the molecular mechanisms revealed that this was due to an increase in microRNA-24 (miR-24) by EBNA2. By using ICOSL 3' untranslated region-luciferase reporter system, we validated that ICOSL is an authentic miR-24 target. Transfection of anti-miR-24 molecules in EBNA2-expressing lymphoma cells reconstituted ICOSL expression and increased tumor immunogenicity in mixed lymphocyte reactions. Because miR-24 is known to target c-MYC, an oncoprotein positively regulated by EBNA2, we analyzed its expression in anti-miR-24 transfected lymphoma cells. Indeed, the reduction of miR-24 in EBNA2-expressing DLBCL further elevated c-MYC and increased apoptosis. Consistent with the in vitro data, EBNA2-positive DLBCL biopsies expressed low ICOSL and high miR-24. We suggest that EBV evades host immune responses through EBNA2 by inducing miR-24 to reduce ICOSL expression, and for simultaneous rheostatic maintenance of proproliferative c-MYC levels. Overall, these data identify miR-24 as a potential therapeutically relevant target in EBV-associated lymphomas.

Overall Survival with Brentuximab Vedotin in Stage III or IV Hodgkin's Lymphoma.

BACKGROUND: Five-year follow-up in a trial involving patients with previously untreated stage III or IV classic Hodgkin's lymphoma showed long-term progression-free survival benefits with first-line therapy with brentuximab vedotin, a CD30-directed antibody-drug conjugate, plus doxorubicin, vinblastine, and dacarbazine (A+AVD), as compared with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). A planned interim analysis indicated a potential benefit with regard to overall survival; data from a median of 6 years of follow-up are now available. METHODS: We randomly assigned patients in a 1:1 ratio to receive up to six cycles of A+AVD or ABVD. The primary end point, modified progression-free survival, has been reported previously. The key secondary end point was overall survival in the intention-to-treat population. Safety was also assessed. RESULTS: A total of 664 patients were assigned to receive A+AVD and 670 to receive ABVD. At a median follow-up of 73.0 months, 39 patients in the A+AVD group and 64 in the ABVD group had died (hazard ratio, 0.59; 95% confidence interval [CI], 0.40 to 0.88; P = 0.009). The 6-year overall survival estimates were 93.9% (95% CI, 91.6 to 95.5) in the A+AVD group and 89.4% (95% CI, 86.6 to 91.7) in the ABVD group. Progression-free survival was longer with A+AVD than with ABVD (hazard ratio for disease progression or death, 0.68; 95% CI, 0.53 to 0.86). Fewer patients in the A+AVD group than in the ABVD group received subsequent therapy, including transplantation, and fewer second cancers were reported with A+AVD (in 23 vs. 32 patients). Primary prophylaxis with granulocyte colony-stimulating factor was recommended after an increased incidence of febrile neutropenia was observed with A+AVD. More patients had peripheral neuropathy with A+AVD than with ABVD, but most patients in the two groups had resolution or amelioration of the event by the last follow-up. CONCLUSIONS: Patients who received A+AVD for the treatment of stage III or IV Hodgkin's lymphoma had a survival advantage over those who received ABVD. (Funded by Takeda Development Center Americas and Seagen; ECHELON-1 ClinicalTrials.gov number, NCT01712490; EudraCT number, 2011-005450-60.).

Brentuximab Vedotin with Chemotherapy in Pediatric High-Risk Hodgkin's Lymphoma.

BACKGROUND: In adults with advanced-stage Hodgkin's lymphoma, the CD30-directed antibody-drug conjugate brentuximab vedotin combined with multiagent chemotherapy has been shown to have greater efficacy, but also more toxic effects, than chemotherapy alone. The efficacy of this targeted therapy approach in children and adolescents with Hodgkin's lymphoma is unclear. METHODS: We conducted an open-label, multicenter, randomized, phase 3 trial involving patients 2 to 21 years of age with previously untreated Hodgkin's lymphoma of stage IIB with bulk tumor or stage IIIB, IVA, or IVB. Patients were assigned to receive five 21-day cycles of brentuximab vedotin with doxorubicin, vincristine, etoposide, prednisone, and cyclophosphamide (brentuximab vedotin group) or the standard pediatric regimen of doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide (standard-care group). Slow-responding lesions, defined by a score of 4 or 5 (on a 5-point scale, with scores of 1 to 3 indicating rapid-responding lesions), were identified on centrally reviewed positron-emission tomography-computed tomography after two cycles. Involved-site radiation therapy was administered after the fifth cycle of therapy to slow-responding lesions and to large mediastinal adenopathy that was present at diagnosis. The primary end point was event-free survival, defined as the time until disease progression occurred, relapse occurred, a second malignant neoplasm developed, or the patient died. Safety and overall survival were assessed. RESULTS: Of 600 patients who were enrolled across 153 institutions, 587 were eligible. At a median follow-up of 42.1 months (range, 0.1 to 80.9), the 3-year event-free survival was 92.1% (95% confidence interval [CI], 88.4 to 94.7) in the brentuximab vedotin group, as compared with 82.5% (95% CI, 77.4 to 86.5) in the standard-care group (hazard ratio for event or death, 0.41; 95% CI, 0.25 to 0.67; P<0.001). The percentage of patients who received involved-site radiation therapy did not differ substantially between the brentuximab vedotin group and the standard-care group (53.4% and 56.8%, respectively). Toxic effects were similar in the two groups. Overall survival at 3 years was 99.3% (95% CI, 97.3 to 99.8) in the brentuximab vedotin group and 98.5% (95% CI, 96.0 to 99.4) in the standard-care group. CONCLUSIONS: The addition of brentuximab vedotin to standard chemotherapy resulted in superior efficacy, with a 59% lower risk of an event or death, and no increase in the incidence of toxic effects at 3 years. (Funded by the National Institutes of Health and others; AHOD1331 ClinicalTrials.gov number, NCT02166463.).

Specific Polo-Like Kinase 1 Expression in Nodular Lymphocyte-Predominant Hodgkin Lymphoma Suggests an Intact Immune Surveillance Program.

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare and relatively indolent B-cell lymphoma. Characteristically, the [lymphocyte-predominant (LP)] tumor cells are embedded in a microenvironment enriched in lymphocytes. More aggressive variants of mature B-cell and peripheral T-cell lymphomas exhibit nuclear expression of the polo-like kinase 1 (PLK1) protein, stabilizing MYC (alias c-myc) and associated with worse clinical outcomes. This study demonstrated expression of PLK1 in the LP cells in 100% of NLPHL cases (n = 76). In contrast, <5% of classic Hodgkin lymphoma cases (n = 70) showed PLK1 expression within the tumor cells. Loss-of-function approaches demonstrated that the expression of PLK1 promoted cell proliferation and increased MYC stability in NLPHL cell lines. Correlation with clinical parameters revealed that the increased expression of PLK1 was associated with advanced-stage disease in patients with NLPHL. A multiplex immunofluorescence panel coupled with artificial intelligence algorithms was used to correlate the composition of the tumor microenvironment with the proliferative stage of LP cells. The results showed that LP cells with PLK1 (high) expression were associated with increased numbers of cytotoxic and T-regulatory T cells. Overall, the findings demonstrate that PLK1 signaling increases NLPHL proliferation and constitutes a potential vulnerability that can be targeted with PLK1 inhibitors. An active immune surveillance program in NLPHL may be a critical mechanism limiting PLK1-dependent tumor growth.

Elevated serum TARC levels precede classic Hodgkin lymphoma diagnosis by several years.

Tumor cells in classic Hodgkin lymphoma produce high quantities of the thymus- and activation-related chemokine (TARC). We measured TARC levels in prediagnostic serum samples and found strikingly increased values in the vast majority of patients, as early as 6 years before diagnosis.

Novel insights into Hodgkin lymphoma biology by single-cell analysis.

The emergence and rapid development of single-cell technologies mark a paradigm shift in cancer research. Various technology implementations represent powerful tools to understand cellular heterogeneity, identify minor cell populations that were previously hard to detect and define, and make inferences about cell-to-cell interactions at single-cell resolution. Applied to lymphoma, recent advances in single-cell RNA sequencing have broadened opportunities to delineate previously underappreciated heterogeneity of malignant cell differentiation states and presumed cell of origin, and to describe the composition and cellular subsets in the ecosystem of the tumor microenvironment (TME). Clinical deployment of an expanding armamentarium of immunotherapy options that rely on targets and immune cell interactions in the TME emphasizes the requirement for a deeper understanding of immune biology in lymphoma. In particular, classic Hodgkin lymphoma (CHL) can serve as a study paradigm because of its unique TME, featuring infrequent tumor cells among numerous nonmalignant immune cells with significant interpatient and intrapatient variability. Synergistic to advances in single-cell sequencing, multiplexed imaging techniques have added a new dimension to describing cellular cross talk in various lymphoma entities. Here, we comprehensively review recent progress using novel single-cell technologies with an emphasis on the TME biology of CHL as an application field. The described technologies, which are applicable to peripheral blood, fresh tissues, and formalin-fixed samples, hold the promise to accelerate biomarker discovery for novel immunotherapeutic approaches and to serve as future assay platforms for biomarker-informed treatment selection, including immunotherapies.

Pembrolizumab plus vorinostat induces responses in patients with Hodgkin lymphoma refractory to prior PD-1 blockade.

This phase 1 study evaluated the addition of vorinostat to pembrolizumab in patients with relapsed/refractory (RR) classical Hodgkin lymphoma (cHL), diffuse large B-cell lymphoma, and follicular lymphoma. We report the results in cases of cHL. Adult patients with RR cHL who had received ≥1 prior lines of therapy and were ineligible for transplantation were treated in a dose-escalation cohort with 2 dose levels (DLs) and then on an expansion cohort at the recommended phase 2 dose (RP2D) in 21-day cycles. Vorinostat 100 mg twice a day (DL1) and 200 mg twice a day (DL2) was administered orally from days 1 to 5 and 8 to 12; all patients received pembrolizumab 200 mg IV every 3 weeks. The primary end point was safety and determination of RP2D. In total, 32 patients with cHL were enrolled, including 30 at DL2 (RP2D); 78% had received prior anti-programmed cell death 1 (anti-PD-1) therapy, and 56% were PD-1 refractory. Grade ≥3 adverse events (AEs) included hypertension (9%), neutropenia (9%), hypophosphatemia (9%), thrombocytopenia (6%), and lymphopenia (6%). Immune-related AEs included grade 1 or 2 thyroiditis (13%), grade 1 rash (6%), and grade 3 esophagitis/duodenitis (3%). The overall response rate (ORR) was 72% and complete response (CR) rate was 34%. Patients refractory to prior PD-1 blockade (n = 18) had ORR and CR rates of 56% and 11%, respectively. Pembrolizumab and vorinostat was well tolerated with a high ORR rate in RR cHL including in anti-PD-1-refractory disease. This trial was registered at www.clinicaltrials.gov as #NCT03150329.

Five-year follow-up of KEYNOTE-087: pembrolizumab monotherapy for relapsed/refractory classical Hodgkin lymphoma.

Previous analyses of the phase 2 KEYNOTE-087 (NCT02453594) trial of pembrolizumab monotherapy demonstrated effective antitumor activity with acceptable safety in patients with relapsed or refractory (R/R) classical Hodgkin lymphoma (cHL). However, long-term response durability and outcome of patients who receive a second course after treatment discontinuation after complete response (CR) remain of clinical interest. We present KEYNOTE-087 data after >5 years of median follow-up. Patients with R/R cHL and progressive disease (PD) after autologous stem cell transplantation (ASCT) and brentuximab vedotin (BV; cohort 1), salvage chemotherapy and BV without ASCT (cohort 2), or ASCT without subsequent BV (cohort 3), received pembrolizumab for ≤2 years. Patients in CR who discontinued treatment and subsequently experienced PD were eligible for second-course pembrolizumab. Primary end points were the objective response rate (ORR) using blinded central review and safety. The median follow-up was 63.7 months. ORR was 71.4% (95% confidence interval [CI], 64.8-77.4; CR, 27.6%; partial response, 43.8%). Median duration of response (DOR) was 16.6 months; median progression-free survival was 13.7 months. A quarter of responders, including half of complete responders, maintained a response for ≥4 years. Median overall survival was not achieved. Among 20 patients receiving second-course pembrolizumab, ORR for 19 evaluable patients was 73.7% (95% CI, 48.8-90.8); median DOR was 15.2 months. Any-grade treatment-related adverse events occurred in 72.9% of patients and grade 3 or 4 adverse events occurred in 12.9% of patients; no treatment-related deaths occurred. Single-agent pembrolizumab can induce durable responses, particularly in patients achieving CR. Second-course pembrolizumab frequently reinduced sustained responses after relapse from initial CR.

Discovery of novel predisposing coding and noncoding variants in familial Hodgkin lymphoma.

Familial aggregation of Hodgkin lymphoma (HL) has been demonstrated in large population studies, pointing to genetic predisposition to this hematological malignancy. To understand the genetic variants associated with the development of HL, we performed whole genome sequencing on 234 individuals with and without HL from 36 pedigrees that had 2 or more first-degree relatives with HL. Our pedigree selection criteria also required at least 1 affected individual aged <21 years, with the median age at diagnosis of 21.98 years (3-55 years). Family-based segregation analysis was performed for the identification of coding and noncoding variants using linkage and filtering approaches. Using our tiered variant prioritization algorithm, we identified 44 HL-risk variants in 28 pedigrees, of which 33 are coding and 11 are noncoding. The top 4 recurrent risk variants are a coding variant in KDR (rs56302315), a 5' untranslated region variant in KLHDC8B (rs387906223), a noncoding variant in an intron of PAX5 (rs147081110), and another noncoding variant in an intron of GATA3 (rs3824666). A newly identified splice variant in KDR (c.3849-2A>C) was observed for 1 pedigree, and high-confidence stop-gain variants affecting IRF7 (p.W238∗) and EEF2KMT (p.K116∗) were also observed. Multiple truncating variants in POLR1E were found in 3 independent pedigrees as well. Whereas KDR and KLHDC8B have previously been reported, PAX5, GATA3, IRF7, EEF2KMT, and POLR1E represent novel observations. Although there may be environmental factors influencing lymphomagenesis, we observed segregation of candidate germline variants likely to predispose HL in most of the pedigrees studied.

Concurrent pembrolizumab with AVD for untreated classic Hodgkin lymphoma.

Concurrent administration of pembrolizumab with chemotherapy in untreated classic Hodgkin lymphoma (CHL) has not been studied previously. To investigate this combination, we conducted a single-arm study of concurrent pembrolizumab with AVD (doxorubicin, vinblastine, and dacarbazine; APVD) for untreated CHL. We enrolled 30 patients and met the primary safety end point with no observed significant treatment delays in the first 2 cycles. Twelve patients experienced grade 3 or 4 nonhematologic adverse events (AEs), most commonly febrile neutropenia and infection/sepsis. Grade 3 or 4 immune-related AEs, including alanine aminotransferase elevation and aspartate aminotransferase elevation were observed in 3 patients. One patient experienced an episode of grade 2 colitis and arthritis. Six patients missed at least 1 dose of pembrolizumab because of AEs, primarily grade 2 or higher transaminitis. Among 29 response-evaluable patients, the best overall response rate was 100% and the complete response rate was 90%. With a median follow-up of 2.1 years, the 2-year progression-free survival (PFS) and overall survival were 97% and 100%, respectively. To date, no patient who has withheld or discontinued pembrolizumab because of toxicity has progressed. Clearance of circulating tumor DNA (ctDNA) was associated with superior PFS when measured after cycle 2 and at the end of treatment (EOT). None of the 4 patients with persistent uptake by fluorodeoxyglucose positron emission tomography (PET) at EOT yet negative ctDNA have relapsed to date. Concurrent APVD shows promising safety and efficacy but may yield spurious PET findings in some patients. This trial was registered at www.clinicaltrials.gov as #NCT03331341.

Improved outcomes for relapsed/refractory Hodgkin lymphoma after autologous transplantation in the era of novel agents.

The treatment landscape of relapsed/refractory (R/R) classic Hodgkin lymphoma (cHL) has evolved significantly over the past decade after the approval of brentuximab vedotin (BV) and the programmed death-1 (PD-1) inhibitors. We evaluated how outcomes and practice patterns have changed for patients with R/R cHL who underwent autologous hematopoietic cell transplantation (AHCT) at our institution from 2011 to 2020 (N = 183) compared with those from 2001 to 2010 (N = 159) and evaluated prognostic factors for progression-free survival (PFS) and overall survival (OS) in both eras. OS was superior in the modern era with a trend toward lower nonrelapse mortality beyond 2 years after transplant. Among patients who progressed after AHCT, 4-year postprogression survival increased from 43.3% to 71.4% in the modern era, reflecting increasing use of BV and the PD-1 inhibitors. In multivariable analysis for patients that underwent transplant in the modern era, age ≥45 years, primary refractory disease, and lack of complete remission pre-AHCT were associated with inferior PFS, whereas receipt of a PD-1 inhibitor-based regimen pre-AHCT was associated with superior PFS. Extranodal disease at relapse was associated with inferior OS. Our study demonstrates improved survival for R/R cHL after AHCT in the modern era attributed to more effective salvage regimens allowing for better disease control pre-AHCT and improved outcomes for patients who progressed after AHCT. Excellent outcomes were observed with PD-1 inhibitor-based salvage regimens pre-AHCT and support a randomized trial evaluating immunotherapy in the second line setting.

Spatial and molecular profiling of the mononuclear phagocyte network in classic Hodgkin lymphoma.

Classic Hodgkin lymphoma (cHL) has a rich immune infiltrate, which is an intrinsic component of the neoplastic process. Malignant Hodgkin Reed-Sternberg cells (HRSCs) create an immunosuppressive microenvironment by the expression of regulatory molecules, preventing T-cell activation. It has also been demonstrated that mononuclear phagocytes (MNPs) in the vicinity of HRSCs express similar regulatory mechanisms in parallel, and their presence in tissue is associated with inferior patient outcomes. MNPs in cHL have hitherto been identified by a small number of canonical markers and are usually described as tumor-associated macrophages. The organization of MNP networks and interactions with HRSCs remains unexplored at high resolution. Here, we defined the global immune-cell composition of cHL and nonlymphoma lymph nodes, integrating data across single-cell RNA sequencing, spatial transcriptomics, and multiplexed immunofluorescence. We observed that MNPs comprise multiple subsets of monocytes, macrophages, and dendritic cells (DCs). Classical monocytes, macrophages and conventional DC2s were enriched in the vicinity of HRSCs, but plasmacytoid DCs and activated DCs were excluded. Unexpectedly, cDCs and monocytes expressed immunoregulatory checkpoints PD-L1, TIM-3, and the tryptophan-catabolizing protein IDO, at the same level as macrophages. Expression of these molecules increased with age. We also found that classical monocytes are important signaling hubs, potentially controlling the retention of cDC2 and ThExh via CCR1-, CCR4-, CCR5-, and CXCR3-dependent signaling. Enrichment of the cDC2-monocyte-macrophage network in diagnostic biopsies is associated with early treatment failure. These results reveal unanticipated complexity and spatial polarization within the MNP compartment, further demonstrating their potential roles in immune evasion by cHL.

Interim PET-guided treatment for early-stage NLPHL: a subgroup analysis of the randomized GHSG HD16 and HD17 studies.

The optimal first-line treatment for nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) diagnosed in early stages is largely undefined. We, therefore, analyzed 100 NLPHL patients treated in the randomized HD16 (early-stage favorable; n = 85) and HD17 (early-stage unfavorable; n = 15) studies. These studies investigated the omission of consolidation radiotherapy (RT) in patients with a negative interim positron emission tomography (iPET) (ie, Deauville score <3) after chemotherapy (HD16: 2× doxorubicin, bleomycin, vinblastine, and dacarbazine [ABVD]; HD17: 2× escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone [BEACOPP] plus 2× ABVD). Patients with NLPHL treated in the HD16 and HD17 studies had 5-year progression-free survival (PFS) rates of 90.3% and 92.9%, respectively. Thus, the 5-year PFS did not differ significantly from that of patients with classical Hodgkin lymphoma treated within the same studies (HD16: P = .88; HD17: P = .50). Patients with early-stage favorable NLPHL who had a negative iPET after 2× ABVD and did not undergo consolidation RT tended to have a worse 5-year PFS than patients with a negative iPET who received consolidation RT (83% vs 100%; P = .05). There were 10 cases of NLPHL recurrence. However, no NLPHL patient died during follow-up. Hence, the 5-year overall survival rate was 100%. Taken together, contemporary Hodgkin lymphoma-directed treatment approaches result in excellent outcomes for patients with newly diagnosed early-stage NLPHL and, thus, represent valid treatment options. In early-stage favorable NLPHL, consolidation RT appears necessary after 2× ABVD to achieve the optimal disease control irrespective of the iPET result.

Nivolumab and brentuximab vedotin with or without bendamustine for R/R Hodgkin lymphoma in children, adolescents, and young adults.

Children, adolescents, and young adults (CAYA) with relapsed/refractory (R/R) classic Hodgkin lymphoma (cHL) without complete metabolic response (CMR) before autologous hematopoietic cell transplantation (auto-HCT) have poor survival outcomes. CheckMate 744, a phase 2 study for CAYA (aged 5-30 years) with R/R cHL, evaluated a risk-stratified, response-adapted approach with nivolumab plus brentuximab vedotin (BV) followed by BV plus bendamustine for patients with suboptimal response. Risk stratification was primarily based on time to relapse, prior treatment, and presence of B symptoms. We present the primary analysis of the standard-risk cohort. Data from the low-risk cohort are reported separately. Patients received 4 induction cycles with nivolumab plus BV; those without CMR (Deauville score >3, Lugano 2014) received BV plus bendamustine intensification. Patients with CMR after induction or intensification proceeded to consolidation (high-dose chemotherapy/auto-HCT per protocol). Primary end point was CMR any time before consolidation. Forty-four patients were treated. Median age was 16 years. At a minimum follow-up of 15.6 months, 43 patients received 4 induction cycles (1 discontinued), 11 of whom received intensification; 32 proceeded to consolidation. CMR rate was 59% after induction with nivolumab plus BV and 94% any time before consolidation (nivolumab plus BV ± BV plus bendamustine). One-year progression-free survival rate was 91%. During induction, 18% of patients experienced grade 3/4 treatment-related adverse events. This risk-stratified, response-adapted salvage strategy had high CMR rates with limited toxicities in CAYA with R/R cHL. Most patients did not require additional chemotherapy (bendamustine intensification). Additional follow-up is needed to confirm durability of disease control. This trial was registered at www.clinicaltrials.gov as #NCT02927769.

Tumor microenvironment contribution to checkpoint blockade therapy: lessons learned from Hodgkin lymphoma.

Classic Hodgkin lymphoma (cHL) is characterized by a tumor microenvironment (TME) containing inflammatory/immune cells. Follicular lymphoma, mediastinal gray zone lymphoma, and diffuse large B-cell lymphomas may show a TME containing inflammatory/immune cells, but the TMEs are quite different. In B-cell lymphomas and cHL, programmed cell death 1 (PD-1)-PD ligand 1 pathway blockade drugs differ in their effectiveness among patients with refractory/relapsed disease. Further research should explore innovative assays that could reveal which molecules influence sensitivity or resistance to therapy in an individual patient.

Representation of the population in need for pivotal clinical trials in lymphomas.

Despite the advances in cancer outcomes, significant health disparities persist. Several new agents have been recently approved for treatment of lymphomas, leading to improved outcomes. Extending the benefits of these new agents starts by adequate enrollment of all affected patient populations. This study aimed to evaluate the extent to which randomized controlled trials (RCTs) match the demographic and geographic diversity of the population affected by lymphoma. Two Food and Drug Administration databases, clinicaltrials.gov, and relevant primary manuscripts were reviewed for drug approval data and demographic representation in RCTs for classical Hodgkin lymphoma (cHL) and non-Hodgkin lymphoma. Maps showing the distribution and frequency of trial participation relative to disease burden, insurance status, and racial representation were created. Black, Hispanic, and female patients were significantly underrepresented in the RCTs for lymphoma compared with that for the disease burden (3.6% [95% confidence interval (CI), 2.8-5.4] vs 14.6% [95% CI, 13.8-15.3]; 6.7% [95% CI, 5.5-7.9] vs 16.3% [95% CI, 15.5-17.1]; and 39.1% [95% CI, 37.3-40.9] vs 42.7% [95% CI, 42.3-43.1], respectively). White and male patients were overrepresented. More counties with higher mortality rates and racial minority representation had low access to the trials, particularly for cHL in the southern region of the United States. There are significant racial misrepresentations in pivotal RCTs in the United States, and geographic distribution of these trials may not provide easy access to all patients in need. Disparities in enrollment should be corrected to make results applicable to all populations.

Risk of male breast cancer after Hodgkin lymphoma.

Female survivors of Hodgkin lymphoma (HL) treated with chest radiotherapy have a strongly increased risk of breast cancer (BC), but the treatment-specific BC risk in male survivors of HL has not been evaluated. We assessed BC risk in a cohort of 3077 male survivors of 5-year HL treated at age ≤51 years in 20 Dutch hospitals between 1965 and 2013. We estimated standardized incidence ratios (SIRs), absolute excess risks per 10 000 person-years, and cumulative BC incidences. After a 20-year median follow-up, we observed 8 cases of male with BC. Male survivors of HL experienced a 23-fold (95% confidence interval [CI], 10.1-46.0) increased BC risk compared with the general population, representing 1.6 (95% CI, 0.7-3.3) excess BC incidences per 10 000 person-years. The 20- and 40-year cumulative BC incidences after HL treatment were 0.1% (95% CI, 0.02-0.3) and 0.7% (95% CI, 0.3-1.4), respectively. Treatment with chest radiotherapy without alkylating chemotherapy yielded a strongly increased SIR (20.7; 95% CI, 2.5-74.8), which was not significantly different for chest radiotherapy and alkylating chemotherapy (41.1; 95% CI, 13.4-96.0). Males treated with chest radiotherapy and anthracyclines had an SIR of 48.1 (95% CI, 13.1-123.1). Two patients died from BC (median follow-up, 4.7 years). To ensure early diagnosis and treatment, clinicians should be alert to BC symptoms in male survivors of HL.