Incorporating novel agents into frontline treatment of Hodgkin lymphoma

Classical Hodgkin lymphoma (cHL) is associated with excellent outcomes with standard frontline chemotherapy or combined modality therapy. However, up to 25% of patients will have relapsed or primary refractory (RR) cHL. Improving the cure rate with frontline treatment, treatment-related complications and late effects, and poor therapy tolerance with high relapse rates in older patients are unmet needs in the initial management of cHL. The introduction of novel therapies, including the CD30-directed antibody drug conjugate brentuximab vedotin and PD-1 blockade (ie, pembrolizumab or nivolumab), has transformed the treatment of RR cHL and has the potential to address these unmet needs in the frontline setting. Incorporation of these potent, targeted immunotherapies into frontline therapy may improve outcomes, may allow for de-escalation of therapy without sacrificing efficacy to reduce treatment complications, and may allow for well-tolerated and targeted escalation of therapy for patients demonstrating an insufficient response. In this article, we provide a case-based approach to the use of novel agents in the frontline treatment of cHL.

High-risk stage IIB Hodgkin lymphoma treated in the H10 and AHL2011 trials: total metabolic tumor volume is a useful risk factor to stratify patients at baseline

Stage IIB Hodgkin lymphoma (HL) patients, with a mediastinum-to-thorax (M/T) ratio of ≥0.33 or extranodal localization have a poor prognosis and are treated either as limited or advanced stage. We compared these two approaches in patients included in two randomized phase III trials enrolling previously untreated early (H10) or advanced stage HL (AHL2011). We included HL patients with Ann-Arbor stage IIB with M/T ≥0.33 or extranodal involvement enrolled in the H10 or AHL2011 trials with available positron emission tomography at baseline (PET0) and after two cycles of chemotherapy (PET2). Baseline total metabolic tumor volume (TMTV) was calculated using the 41% SUVmax method. PET2 response assessment used the Deauville score. One hundred and fourty-eight patients were eligible, including 83 enrolled in the AHL2011 trial and 65 in the H10 trial. The median TMTV value was 155.5 mL (range, 8.3-782.9 mL), 165.6 mL in AHL2011 and 147 mL in H10. PET2 positivity rates were 16.9% (n=14) and 9.2% (n=6) in AHL2011 and H10 patients, respectively. With a median follow-up of 4.1 years (95% confidence interval [CI]: 3.9-4.4), overall 4-year PFS was 88.0%, 87.0% in AHL2011 and 89.2% in H10. In univariate and mutivariate analyses, baseline TMTV and PET2 response influenced significantly progression-free survival (hazard ratio [HR]=4.94, HR=3.49 respectively). Notably, among the 16 patients who relapsed, 13 (81%) had a baseline TMTV baseline ≥155 mL. Upfront ABVD plus radiation therapy or upfront escBEACOPP without radiotherapy provide similar patient's outcome in high-risk stage IIB HL. TMTV is useful to stratify these patients at baseline.

A Real-World Study of Combined Modality Therapy for Early-Stage Hodgkin Lymphoma: Too Little Treatment Impacts Outcome

In the real-world setting, CMT led to improved outcomes for patients with PET2-positive and unfavorable disease.

Similar to clinical trials, favorable, non-bulky, and PET2-negative subgroups had comparable survival outcomes with chemotherapy-alone.

Multiple clinical trials have assessed de-escalation strategies from combined modality therapy (CMT) to chemotherapy-alone for the treatment of early-stage classical Hodgkin lymphoma (cHL), confirming similar outcomes. The application of these data to the real-world is limited, however. We conducted a retrospective, multicenter cohort study comparing CMT vs chemotherapy-alone in patients with early-stage cHL (stage IA-IIB) treated between January 2010 and December 2020. Positron emission tomography (PET) scans after chemotherapy cycle 2 (PET2) were independently reviewed by a nuclear radiologist (Deauville score ≥4, positive; ≤3, negative). Patient outcomes were compared by using an intention-to-treat analysis. Among 125 patients (CMT, n = 63; chemotherapy-alone, n = 62) with a median follow-up of 59.8 months (95% CI, 48.6-71.0), no differences in overall survival were observed (5-year overall survival, CMT 98.0% vs chemotherapy-alone 95.1%; log-rank test, P = .38). However, there was reduced progression-free survival (PFS) with chemotherapy-alone among all patients (2-year PFS, CMT 95.1% vs chemotherapy-alone 75.3%; log-rank test, P = .005) and in those with bulky (n = 43; log-rank test, P < .001), unfavorable (n = 81; log-rank test, P = .002), or PET2-positive (n = 15; log-rank test, P = .02) disease. No significant differences in PFS were seen for patients with non-bulky (log-rank test, P = .35), favorable (log-rank test, P = .62), or PET2-negative (log-rank test, P = .19) disease. Based on our real-world experience, CMT seems beneficial for patients with early-stage cHL, especially those with PET2-positive and unfavorable disease. Chemotherapy-alone regimens can lead to comparable outcomes for patients with favorable, non-bulky, or PET2-negative disease. We conclude that although results seen in clinical trials are replicated in certain patient subgroups, other subgroups not fitting trial criteria do poorly when radiotherapy is excluded.

American Society of Clinical Oncology 2021 Annual Meeting Highlights for Radiation Oncologists

The annual meeting of the American Society of Clinical Oncology is the largest multidisciplinary oncology-focused conference in the world. With more than 4900 total abstracts in 2021 alone, it is difficult for individuals to evaluate all the results. This article presents a review of 32 selected abstracts across all disease sites, focusing on those of greatest relevance to radiation oncologists.

Controversies in the management of early-stage Hodgkin lymphoma

Positron emission tomography (PET)-adapted chemotherapy and radiotherapy approaches are currently used for the initial treatment of early-stage Hodgkin lymphoma (HL) with progression-free survival and overall survival exceeding 85% and 95%, respectively. However, despite general agreement on the prognostic value of interim PET in HL, frontline treatment approaches vary among institutions with respect to how pretreatment clinical risk factors determine treatment selection, the definition of PET negativity, which chemotherapy regimen to initiate and how many cycles to administer, and when to incorporate radiation. Furthermore, as recent trials have confirmed improved efficacy and manageable toxicity when brentuximab and checkpoint inhibitors are combined with frontline regimens such as doxorubicin, vinblastine, and dacarbazine in advanced-stage HL, these agents are now under evaluation as frontline therapy in early-stage HL. A number of issues will affect the use of these agents in early-stage HL, including the costs, early and late toxicities with these agents, patient population (favorable or unfavorable risk groups), how to incorporate them (concurrently or sequentially), and whether they can ultimately replace cytotoxic therapy with similar efficacy and fewer late effects. Future treatment paradigms for early-stage HL may change significantly once randomized studies are completed incorporating these agents into frontline therapy. Ideally, frontline use of brentuximab and checkpoint inhibitors in early-stage HL will result in improved outcomes compared with current PET-adapted approaches with decreased risks of late toxicities that continue to afflict long-term survivors of HL.