Kelly, Kara M.

AbstractPurpose/objectiveWe compared the prognostic value of chest radiograph (CXR)‐ and computed tomography (CT)‐derived definition of large mediastinal adenopathy (LMA) in pediatric Hodgkin lymphoma (HL).Materials/methodsTotal 143 patients treated for stage IIIB/IVB HL on COG AHOD0831 were included in this study. Six definitions of LMA were investigated: (i) mediastinal mass ratio on CXR (MRCXR) > 1/3; (ii) mediastinal mass ratio on CT (MRCT) > 1/3; (iii) mediastinal mass volume on CT (MVCT) > 200 mL; (iv) normalized mediastinal mass volume (MVCT/thoracic diameter [TD]) > 1 mL/mm; (v) mediastinal mass diameter on CT (MDCT) > 10 cm; and (vi) normalized mediastinal mass diameter (MDCT/TD) > 1/3.ResultsMedian age at diagnosis was 15.8 years (range: 5.2–21.3 years). In patients with a slow early response (SER) to chemotherapy, MVCT > 200 mL, MDCT > 10 cm, and MDCT/TD > 1/3 were associated with worse relapse‐free survival (RFS) on MVA, while MRCXR > 1/3, MRCT > 1/3, and MVCT/TD > 1 mL/mm trended toward worse RFS; MDCT/TD was the most strongly prognostic for inferior RFS, with a hazard ratio of 6.41 for MDCT/TD > 1/3 versus ≤1/3 on MVA (p = .02).ConclusionLMA according to MVCT > 200 mL, MDCT > 10 cm, and MDCT/TD > 1/3 is associated with poor prognosis in advanced‐stage HL patients with SER. The normalized mediastinal diameter, MDCT/TD > 1/3 appears to be the strongest predictor of inferior RFS.

SummaryThe Children's Oncology Group AHOD0831 study used a positron emission tomography (PET) response‐adapted approach in high‐risk Hodgkin lymphoma, whereby slow early responders (SERs) received more intensive therapy than rapid early responders (RERs). We explored if baseline PET‐based characteristics would improve risk stratification. Of 166 patients enrolled in the COG AHOD0831 study, 94 (57%) had baseline PET scans evaluable for quantitative analysis. For these patients, total body metabolic tumour volume (MTV), total lesion glycolysis (TLG), maximum standardized uptake value (SUVmax) and peak SUV (SUVpeak) were obtained. MTV/TLG thresholds were an SUV of 2.5 (MTV2.5/TLG2.5) and 40% of the tumour SUVmax (MTV40%/TLG40%). TLG2.5 was associated with event‐free survival (EFS) in the complete cohort (p = 0.04) and in RERs (p = 0.01), but not in SERs (p = 0.8). The Youden index cut‐off for TLG2.5 was 1841. Four‐year EFS was 92% for RER/TLG2.5 up to 1841, 60% for RER/TLG2.5 greater than 1841, 74% for SER/TLG2.5 up to 1841 and 79% for SER/TLG2.5 greater than 1841. Second EFS for RER/TLG2.5 up to 1841 was 100%. Thus, RERs with a low baseline TLG2.5 experienced excellent EFS with less intensive therapy, whereas RERs with a high baseline TLG2.5 experienced poor EFS. These findings suggest that patients with a high upfront tumour burden may benefit from intensified therapy, even if they achieve a RER.

Children, adolescents, and young adults (CAYA) with relapsed/refractory classical 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 relapsed/refractory 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 endpoint 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 PFS 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 relapsed/refractory cHL. Most patients did not require additional chemotherapy (bendamustine intensification). Additional follow-up is needed to confirm durability of disease control. ClinicalTrials.gov: NCT02927769.

Abstract Children’s Oncology Group (COG) trial AHOD0431 reduced systemic therapy and used response-adapted involved-field radiotherapy (IFRT) in early-stage pediatric classic Hodgkin lymphoma. We investigated the impact of positron emission tomographic response after 1 cycle (PET1) and on IFRT outcomes and pattern of relapse. Patients in AHOD0431 underwent PET1 response assessment after AVPC (doxorubicin, vincristine, prednisone, and cyclophosphamide). “Rapid early responders” (RERs) had a negative PET1 (PET1−); “slow early responders” (SERs) had a positive PET1 (PET1+). Patients with a partial response by computed tomographic and functional imaging after 3 chemotherapy cycles received 21-Gy IFRT, whereas complete responders had no IFRT. Progression-free survival (PFS) was evaluated for RERs and SERs treated with or without IFRT. Recurrence sites were initial, new, or both. Relapses involving initial sites were characterized as “within the PET1+ site” or “initially involved but outside the PET1+ site.” Median follow-up was 118 months. The 10-year PFS rate among RERs was 96.6% with IFRT and 84.1% without IFRT (P = .10), whereas SERs were 80.9% with IFRT and 64.0% without IFRT (P = .03). Among 90 RERs who did not receive IFRT, all 14 relapses included an initial site. Among 45 SERs receiving no IFRT, 14 of 16 relapses were in the initial site (9 PET1+ site only). Among 58 patients receiving IFRT, 5 of 10 relapses were in the PET1+ site. After 3 cycles of AVPC alone, RERs showed favorable results. Conversely, SERs had unfavorable outcomes with AVPC alone, although they improved with 21-Gy IFRT. RT remains an important component of treatment for SERs. This trial was registered at www.clinicaltrials.gov as #NCT00302003.

7504 Background: The anti-CD30 antibody drug conjugate, Brentuximab vedotin (Bv) is approved for adults with advanced stage HL but its use has not been established in children or adolescents. We compared the efficacy and safety of Bv with doxorubicin, vincristine, etoposide, prednisone and cyclophosphamide (Bv-AVE-PC) to the standard pediatric dose intensive regimen ABVE-PC, inclusive of bleomycin. Methods: This multicenter randomized, open-label phase 3 study enrolled patients 2-21 years (yrs) with previously untreated HL, stages IIB + bulk, IIIB, IVA, IVB. Patients were randomized to 5 cycles of either ABVE-PC or Bv-AVE-PC given every 21 days with granulocyte colony-stimulating factor support. Centrally reviewed PET-CT after 2 cycles (PET2) identified slow responding lesions (SRL) defined as Deauville score > 3. Involved site radiotherapy (ISRT) was given to bulky mediastinal adenopathy and SRL. The primary objective was 3-year EFS; events include relapse/progression, second malignant neoplasm (SMN) or death. Final data cutoff was 31 December 2021. Results: 600 participants were enrolled across 151 institutions from March 2015 to August 2019; 587 were eligible. Median age was 15.6 yrs (range 3.4-21). Patient and disease characteristics were balanced across study arms. Histology was nodular sclerosing in 76.5%. Stage distribution: 20.6% IIB-bulk; 19.3% IIIB; 28.5% IVA; 31.7% IVB. At a median follow-up of 42.1 mos (0.1-80.9), 3-year EFS (95%CI) by intent-to-treat analyses was 82.5% (77.4, 86.5) with ABVE-PC and 92.1% (88.4, 94.7) with Bv-AVE-PC (HR 0.41 (0.25, 0.67), p = 0.0002). Median time to 1st event was 9.4 months for both arms but the range differs by arm (3.6-57.8 ABVE-PC; 1.3, 25.8 Bv-AVE-PC). Relapse rate was 17% following ABVE-PC and 7% with Bv-AVE-PC. One SMN is noted in each arm: thyroid cancer at 57.8 mos and acute myeloid leukemia at 20.3 mos. 3-year overall survival (95%CI) was 98.5% (96.0, 99.4) for ABVE-PC and 99.3% (97.3, 99.8) for Bv-AVE-PC (p = 0.38). PET2 SRL rates were comparable (ABVE-PC 19% vs. Bv-AVE-PC 18%, p = 0.8). As-treated ISRT receipt did not differ (ABVE-PC 55.7% vs. Bv-AVE-PC 52.7%, p = 0.69). No difference in grade 3/4 adverse events was observed; myelosuppression, reflected in a 32% incidence of > grade 3 febrile neutropenia, did not differ by arm (p = 0.67). Only 19% of patients experienced > grade 2 neuropathy by the Balis pediatric neuropathy scale, with no difference between arms (p = 0.86). Conclusions: Brentuximab vedotin with AVE-PC in a dose intensive regimen has superior efficacy to ABVE-PC for pediatric patients with high-risk HL. A 59% risk reduction in EFS was achieved with no increase in toxicity and with fewer patients receiving ISRT compared to prior pediatric trials for high-risk HL. Clinical trial information: 02166463.

Hodgkin lymphoma (HL) is a highly curable form of cancer, and current treatment regimens are focused on improving treatment efficacy while decreasing the risk of late effects of treatment. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for pediatric HL provide recommendations on the workup, diagnostic evaluation, and treatment of classic HL, including principles of pathology, imaging, staging, systemic therapy, and radiation therapy. This portion of the NCCN Guidelines focuses on the management of pediatric classic HL in the upfront and relapsed/refractory settings.