Subsequent malignant neoplasms among children with Hodgkin lymphoma: a report from the Children's Oncology Group

Molecular Imaging with PET-CT and PET-MRI in Pediatric Musculoskeletal Diseases

Molecular imaging has emerged as an integral part of oncologic imaging. Given the physiologic changes that precede anatomic changes, molecular imaging can enable early detection of disease and monitoring of response. [18F] Fluorodeoxyglucose (FDG) Positron emission tomography (PET) is the predominant molecular imaging modality used in oncologic assessment and can be performed using PET/CT or PET/MR. In pediatric patients, PET/MRI imaging is generally preferred due to low radiation exposure and PET/MRI is particularly advantageous for imaging musculoskeletal (MSK) diseases, as MRI provides superior characterization of tissue changes as compared to CT. In this article, we provide an overview of the typical role of PET CT/MRI in assessment of some common pediatric malignancies and benign MSK diseases with case examples. We also discuss the relative advantages of PET/MRI compared to PET/CT, and review published data with a primary focus on the use of PET/MR.

Improved survival for dose-intensive chemotherapy in primary mediastinal B-cell lymphoma: a systematic review and meta-analysis of 4,068 patients

Primary mediastinal B-cell lymphoma (PMBCL) is a distinct clinicopathologic entity. Currently, there is a paucity of randomized prospective data to inform on optimal front-line chemoimmunotherapy (CIT) and use of consolidative mediastinal radiation (RT). To assess if distinct CIT approaches are associated with disparate survival outcomes, we performed a systematic review and meta-analysis comparing dose-intensive (DI-CIT) versus standard CIT for the front-line treatment of PMBCL. Standard approach (S-CIT) was defined as R-CHOP-21/CHOP-21, with or without RT. DI-CIT were defined as regimens with increased frequency, dose, and/or number of systemic agents. We reviewed data on 4,068 patients (2,517 DI-CIT; 1,551 S-CIT) with a new diagnosis of PMBCL. Overall survival for DI-CIT patients was 88% (95% CI: 85-90) compared to 80% for the S-CIT cohort (95% CI: 74-85). Meta-regression revealed an 8% overall survival (OS) benefit for the DI-CIT group (P<0.01). Survival benefit was maintained when analyzing rituximab only regimens; OS was 91% (95% CI: 89-93) for the rituximab-DI-CIT arm compared to 86% (95% CI: 82-89) for the R-CHOP-21 arm (P=0.03). Importantly, 55% (95% CI: 43-65) of the S-CIT group received RT compared to 22% (95% CI: 15-31) of DI-CIT patients (meta-regression P<0.01). To our knowledge, this is the largest meta-analysis reporting efficacy outcomes for the front-line treatment of PMBCL. DI-CIT demonstrates a survival benefit, with significantly less radiation exposure, curtailing long-term toxicities associated with radiotherapy. As we await results of randomized prospective trials, our study supports the use of dose-intensive chemoimmunotherapy for the treatment of PMBCL.

Case report: Pulmonary synovial sarcoma in a long-term survivor of childhood Hodgkin lymphoma

Solid organ malignancies have been reported in survivors of Hodgkin lymphoma treated with chemoradiation; however, to the best of our knowledge no cases of pulmonary synovial sarcoma have been documented in the literature in this cohort. We herein provide a detailed description of synovial sarcoma occurring in the lung of a long-term survivor of childhood Hodgkin lymphoma. A 29-year-old female never smoker with past medical history of Hodgkin lymphoma diagnosed at the age of 7 years and treated with chemotherapy and radiation therapy was admitted for management of pneumothorax. Wedge lung resection of an ulcerated subpleural nodule revealed a malignant spindle cell tumor that based on light microscopic and immunohistochemical features was classified as monophasic synovial sarcoma. The diagnosis was further confirmed by identification of SS18 (SYT) rearrangement by fluorescence in situ hybridization and SS18-SSX1 gene fusion by RNA sequencing. The case documents a rare occurrence of synovial sarcoma in a long-term survivor of childhood Hodgkin lymphoma. While comprising a typical genetic profile for synovial sarcoma, the tumor had unusual histological features such as cystic and low-grade morphology. The case suggests that synovial sarcoma falls within an expanding spectrum of secondary malignancies following prior treatment of Hodgkin lymphoma.

Retrospective single-center experience with OEPA/COPDAC and PET-CT based strategy for pediatric Hodgkin lymphoma in a LMIC setting

ABVD regimen for Hodgkin lymphoma (HL) is frequently used in children and young adults in low-middle income countries (LMIC). The feasibility and safety data for 'non-ABVD' protocols from LMIC is limited. The retrospective study was conducted in a single center in India. The Euronet PHL-C1 based protocol was administered during 2010-19. A PET-CT was performed at diagnosis and following two OEPA cycles. Radiotherapy was administered for inadequate PET response. During the 10-year period, 143 patients with HL were treated. The mean age was 7.8 ± 2.5 years. Bulky disease was observed in 82 (59%). Treatment abandonment was recorded in 13 (9.1%). The median follow-up duration was 46.4 months. An inadequate PET response was observed in 41/119 (34.4%), of which 56.1% received radiotherapy. Twelve (29.3%) patients who were supposed to receive radiotherapy received 2-cycles of COPDAC instead. Sixty-nine episodes of febrile neutropenia were observed in 54 patients. Treatment-related mortality (TRM) was observed in 7 (5.3%). The majority of episodes of febrile neutropenia (61%) and TRM (86%) occurred in the first cycle of OEPA. The 4-year event-free survival (EFS) and overall survival (OS) were 86.2 ± 3.4% and 93.5 ± 2.2%, respectively. Nine (6.3%) patients relapsed. Bulky disease lacked association with inadequate PET response (p = .800) or relapse (p = 1.000). OEPA/COPDAC regimen and response assessment by PET-CT permitted therapy reduction, including radiotherapy. Febrile neutropenia and resultant TRM (5.3%) are concerning and occurred frequently in the first cycle of OEPA. The support system for managing febrile neutropenia should be optimized for administering OEPA in LMIC.

Survival of pediatric Hodgkin lymphoma patients treated with doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide (ABVE-PC) versus doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) at a single institution

BACKGROUND

Adriamycin, bleomycin, vinblastine, dacarbazine (ABVD), the de facto standard of care in adult-onset Hodgkin lymphoma (HL), has not been directly compared to doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide (ABVE-PC), a pediatric-aimed regimen designed to reduce late effects. We aimed to describe the single-institution experience of using both regimens in patients with pediatric HL.

METHODS

This retrospective cohort study evaluated a total of 224 patients diagnosed with HL between 1999 and 2018 at Children's Hospital Los Angeles (CHLA), of which 93 patients were eligible having received ABVD (n = 46) or ABVE-PC (n = 47) chemotherapy as their initial treatment. Descriptive analyses were performed using the Student's t-test or Fisher's exact test. Survival analysis used the Kaplan-Meier method. Events included death, relapse, and secondary malignancy. We also describe the use of radiation therapy, pulmonary toxicity, and cardiomyopathy determined by shortening fraction <29%. Analyses followed an intention-to-treat principle.

RESULTS

There was no difference in baseline characteristics between the patients receiving ABVE-PC or ABVD in regard for stage, risk group, or prognostic variables, such as the presence or absence of "B" symptoms, bulky disease, and extra-nodal involvement. A greater proportion of patients treated with ABVE-PC received consolidating external beam radiation treatment (XRT) either by randomization or by response compared to ABVD (59.6% vs. 32.6%, respectively, p = .01). While not statistically significant, response to therapy, assessed by positron emission tomography/computerized tomography (PET/CT) where available, mirrored the use for radiation (rapid response 58.3% vs. 90.0%, n = 34, p = .11). The median dose of anthracycline (doxorubicin) was the same in patients receiving ABVE-PC versus ABVD (200 vs. 200 mg/m² , interquartile range 200-250 vs. 200-300 mg/m² , p = .002). There was no difference in event-free survival (p = .63) or overall survival (p = .37) with a median follow-up length of 3.9 years.

CONCLUSIONS

ABVD and ABVE-PC achieved similar survival outcomes in our single-institution cohort.

Racial/Ethnic Disparities on the Risk of Second Malignant Neoplasm Among Hodgkin Lymphoma Survivors

Background

Hodgkin lymphoma survivors are at risk for second malignant neoplasm (SMN). How race/ethnicity affects the risk remains unclear.

Methods

This retrospective cohort study included 22,415 patients diagnosed with primary Hodgkin lymphoma from January 1992 to December 2015 in 13 Surveillance, Epidemiology, and End Results-based registries and divided patients into four groups: non-Hispanic whites, non-Hispanic blacks, Hispanics, and Asian/others. Taking non-Hispanic whites as a reference, both the proportional subdistribution hazard (PSH) and the cause-specific hazard (CSH) methods were used to calculate the SMN hazard ratio for other racial/ethnic groups with and without considering the competing mortality risk.

Results

1,778 patients developed SMN with a median follow-up of 11.63 years. In the adjusted PSH model, Hispanic, Asian/others, and non-Hispanic black patients had 26% (PSH, 0.74; 95% CI, 0.63–0.87), 20% (PSH, 0.80; 95% CI, 0.64–1.01), and 12% (PSH, 0.88; 95% CI, 0.75–1.03) decreased overall SMN hazard, respectively. Moreover, the PSH method revealed the racial/ethnic difference in the SMN risk in the skin, the respiratory system, and the endocrine system. These hazards were slightly higher and different with the use of the CSH approach. In addition to the aforementioned overall SMN and subtypes, adjusted CSH analysis also revealed the racial/ethnic disparities in the risk of subsequent female breast cancer, digestive cancer, and non-Hodgkin lymphoma.

Conclusions

The subtype and SMN risk among Hodgkin lymphoma survivors varied by race/ethnicity. The use of CSH and PSH provides a dynamic view of racial/ethnic effects on SMN risk in Hodgkin lymphoma survivors.

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.

Evaluation of routine CT scans in the follow-up of diffuse large B-cell lymphomas

OBJECTIVE

Our aim was to retrospectively assess the role of routine CT scans within the first year of follow-up with a limited surveillance policy prior to Lugano recommendations in diffuse large B-cell lymphomas (DLBCL) achieving complete metabolic remission (CMR). We also evaluated the type of relapse detection and exposure to CT scans within the first five years.

METHODS

Patients diagnosed with DLBCL who achieved CMR after first-line immunochemotherapy were included. Imaging studies and medical records were thoroughly reviewed.

RESULTS

Among 101 DLBCL patients in the first CMR, a total of 19 relapses were identified in the study period (18.8% of DLBCL patients included). Nine patients relapsed within the first year (47.4% of all relapses) but only 3 of them were detected by the 202 surveillance CT scans performed during this first year of follow-up.

CONCLUSIONS

Our real-world data provide clinically applicable results which are in agreement with the Lugano recommendations based on trial data, highlighting the lack of utility of routine CTs in DLBCL patients achieving CMR.