Schwartz, Cindy L.

ABSTRACT Purpose Despite 5‐year survival rates of over 90% among children and adolescents/young adults (CAYAs) with classic Hodgkin lymphoma (cHL), 15%–20% relapse after frontline therapy. Prior analysis of frontline Children's Oncology Group (COG) clinical trials demonstrated that, despite similar rates of relapse, non‐Hispanic Black (NHB) and Hispanic (vs. non‐Hispanic White [NHW]) patients experienced higher post‐relapse mortality. It is unknown whether post‐relapse disparities persist when second‐line treatment is delivered in a cooperative group trial setting. We examined overall survival (OS) by race and ethnicity in CAYAs enrolled in COG trials for relapsed/refractory (r/r) cHL. Methods A pooled analysis of individual‐level data from CAYAs (≤ 29 years) receiving therapy for r/r cHL on COG clinical trials (2001–2016) was conducted. The Kaplan–Meier method estimated 3‐year OS by racial and ethnic groups. Cox regression models examined associations of race and ethnicity and OS, adjusted for age, insurance, first versus ≥2 relapse, and time from initial diagnosis to relapse trial enrollment. Results Among 175 CAYAs treated on COG trials for r/r cHL (5.7% Asian or Pacific Islander, 14.9% Hispanic, 14.3% NHB, 61.7% NHW, 3.4% other), at median follow‐up of 4.9 years, 3‐year OS was 82.1% (95% confidence interval [CI], 75.3%–87.1%) and did not differ by race and ethnicity ( p = 0.36). In multivariable analyses, shorter time from diagnosis to relapse trial enrollment ( p = 0.01) and ≥2 relapses (vs. first, p = 0.004) conferred worse OS, with no significant effect of race and ethnicity ( p = 0.43). Conclusion Post‐relapse survival did not differ by race and ethnicity among CAYAs enrolled in COG trials for r/r cHL, suggesting access to clinical trials may mitigate OS disparities.

This nonrandomized clinical trial reports outcomes for children with low-risk relapsed Hodgkin lymphoma treated with second-line chemotherapy and involved-field radiotherapy without autologous stem cell transplant.

Purpose In lymphomas, the Deauville score (DS) standardizes 18F-FDG PET treatment response assessments. We assessed interobserver agreement of the DS and developed a quantitative PET-based parameter to minimize subjectivity of response assessments. Methods PET scans performed within the Children’s Oncology Group AHOD0831 study were analyzed. One hundred one scans obtained after the first cycle of chemotherapy (PET1) and 83 obtained after the second cycle (PET2) were eligible for inclusion. Each scan was assigned a DS by 2 nuclear medicine radiologists and a Hodgkin lymphoma index (HLI), defined as the ratio of the tumor’s SUVmax or SUVpeak to the liver’s SUVmean. Cohen κ coefficient measured the rate of agreement of the DS assigned by the 2 radiologists. Receiver operating characteristic curves and the Youden index were used with the consensus DS to identify an optimal HLI cutoff value to distinguish PET-negative from PET-positive images. For each HLI cutoff value, sensitivity, specificity, and accuracy were calculated. Results Interobserver agreement in DS was moderate (PET1: κ = 0.480, P < 0.001; PET2: κ = 0.428, P < 0.001). On PET1, the optimal cutoff values for HLImax were 1.19 for DS2/DS3 and 1.78 for DS3/DS4, and for HLIpeak were 1.19 for DS2/DS3 and 1.44 for DS3/DS4. On PET2 images, the corresponding values were 1.18, 1.58, 0.94, and 1.26. The most accurate predictor was HLImax on PET2 when scans were dichotomized as DS1–DS3 versus DS4–DS5 (accuracy, 92.8%; sensitivity, 100%; specificity, 91.8%). Conclusion The HLI provides an objective, quantitative measure of disease response and thus may improve interreader agreement for lymphoma response assessments.

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.

AbstractBackgroundPositron emission tomography (PET)‐based measures of baseline total‐body tumor burden may improve risk stratification in intermediate‐risk Hodgkin lymphoma (HL).Materials and methodsEvaluable patients were identified from a cohort treated homogeneously with the same combined modality regimen on the Children's Oncology Group AHOD0031 study. Eligible patients had high‐quality baseline PET scans. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were each measured based on 15 thresholds for every patient. Univariate and multivariable Cox regression and Kaplan–Meier survival analyses assessed for an association of MTV and TLG with event‐free survival (EFS).ResultsFrom the AHOD0031 cohort (n = 1712), 86 patients were identified who (i) were treated with four cycles of doxorubicin, bleomycin, vincristine, etoposide, prednisone, cyclophosphamide (ABVE‐PC) chemotherapy followed by involved field radiotherapy, and (ii) had a baseline PET scan that was amenable to quantitative analysis. Based on univariate Cox regression analysis, six PET‐derived parameters were significantly associated with EFS. For each of these, Kaplan–Meier analyses and the log‐rank test were used to compare patients with highest tumor burden (i.e., highest 15%) to the remainder of the cohort. EFS was significantly associated with all six PET parameters (all p < .029). In a multivariable model controlling for important covariates including disease bulk and response to chemotherapy, MTV2BP was significantly associated with EFS (p = .012).ConclusionMultiple baseline PET‐derived volumetric parameters were associated with EFS. MTV2BP was highly associated with EFS when controlling for disease bulk and response to chemotherapy. Incorporation of baseline MTV into risk‐based treatment algorithms may improve outcomes in intermediate‐risk HL.