Radiotherapy across pediatric Hodgkin lymphoma research group protocols: a report from the Staging, Evaluation, and Response Criteria Harmonization (SEARCH) for childhood, adolescent, and young adult Hodgkin lymphoma (CAYAHL) Group

Pediatric Lymphomas: Key Concepts and Clinical Approaches for Pediatricians

Lymphomas are the third most prevalent pediatric cancer following leukemia and brain tumors, representing 10% to15% of all childhood cancers. We can divide lymphomas into Hodgkin and non-Hodgkin lymphomas, with marked differences between these 2 groups. Clinical manifestations can be insidious, and clinicians should have a high index of suspicion when treating patients with lymphadenopathies, weight loss, or prolonged fever. Although refinements in chemotherapy regimens have improved survival for pediatric lymphomas, more recent successful incorporation of targeted therapies offers hope for even better outcomes with fewer late effects. Given the excellent prognosis for many of these patients, it is increasingly important for primary care physicians to recognize and manage potential late effects of therapy, both physical and psychological.

Hodgkin lymphoma involving the extra-axial CNS: an AHOD1331, PHL-C1, and PHL-C2 report from the COG and EuroNet-PHL

ABSTRACT

Hodgkin lymphoma (HL) involving the central nervous system (CNS) is exceedingly rare. Information regarding the presentation, management, treatment, and outcome of patients with CNS HL is limited to case reports or small series. We describe 45 pediatric patients with 55 extra-axial CNS lesions at diagnosis with HL from a cohort of 4995 patients enrolled on Children's Oncology Group AHOD1331 and the European Network for Pediatric Hodgkin lymphoma C1 and C2 trials, with an overall incidence of 0.9%. Up to 82.2% of patients had a single CNS lesion in the thoracic, lumbar, or sacral spine. In the evaluated cohort, HL did not occur within the CNS parenchyma. Lesions extended into the extra-axial CNS space from adjacent soft tissue or bone and never directly infiltrated through the dura into the brain or spinal cord. Patients with CNS involvement had a twofold greater incidence of extranodal lesions than previously reported cohorts without CNS involvement. After 2 cycles of chemotherapy, 89.1% of CNS lesions demonstrated a complete metabolic response and >75% decrease in volume. Thirteen CNS lesions (23.6%) received irradiation; none were sites of disease relapse. Relapse occurred at the site of 2 lesions involving the CNS, both of which had an adequate interim response to chemotherapy. In summary, we present, to our knowledge, the largest reported cohort of systemic HL involving the CNS at diagnosis, demonstrating that these lesions originate from surrounding tissues, extend into the extra-axial CNS space, and respond similarly to other nodal and extranodal disease. The trials were registered at www.clinicaltrials.gov as #NCT02166463, #NCT00433459, and #NCT02684708.

Pediatric and Adolescent Hodgkin Lymphoma: Paving the Way for Standards of Care and Shared Decision Making

Hodgkin lymphoma (HL) is a treatable cancer with an incidence peak in adolescent and young adult years. Treatment strategies have been developed to balance the intensity of therapy needed to maintain disease-free survival while simultaneously preserving overall survival. Risk-based, response-adapted frontline therapy has long used a combination of chemotherapy and radiotherapy (RT). Successive clinical trials over the past three decades have safely reduced cumulative alkylator, anthracycline, and RT exposures for many patients. The advent of checkpoint inhibitors and the CD30-targeted antibody drug conjugate, brentuximab vedotin, has provided new options for de-escalation of conventional therapies associated with late effects in survivors treated at a young age. The ability to evaluate novel agents has been accelerated in collaborative trials inclusive of children and adolescents within the US National Clinical Trials Network and between the Children's Oncology Group and the EuroNet Pediatric Hodgkin Lymphoma Consortium. With numerous treatment options, patients with HL and their clinicians have an opportunity for shared decision making from diagnosis, through cancer treatment, and into survivorship. Given excellent survival outcomes, decisions about treatment in classic HL should be collaborative and attention to long-term survivorship needs should remain a high priority. Patient-reported outcomes remain an important tool to aid clinicians working with survivors to optimize health status and related quality of life for decades after HL therapy.

Accelerating pediatric Hodgkin lymphoma research: the Hodgkin Lymphoma Data Collaboration (NODAL)

Data commons have proven to be an indispensable avenue for advancing pediatric cancer research by serving as unified information technology platforms that, when coupled with data standards, facilitate data sharing. The Pediatric Cancer Data Commons, the flagship project of Data for the Common Good (D4CG), collaborates with disease-based consortia to facilitate development of clinical data standards, harmonization and pooling of clinical data from disparate sources, establishment of governance structure, and sharing of clinical data. In the interest of international collaboration, researchers developed the Hodgkin Lymphoma Data Collaboration and forged a relationship with the Pediatric Cancer Data Commons to establish a data commons for pediatric Hodgkin lymphoma. Herein, we describe the progress made in the formation of Hodgkin Lymphoma Data Collaboration and foundational goals to advance pediatric Hodgkin lymphoma research.

Children's Oncology Group's 2023 blueprint for research: Hodgkin lymphoma

The goal of therapy in pediatric Hodgkin lymphoma (HL) is to maximize overall survival while minimizing the morbidity of curative therapy. Key findings from recent Children's Oncology Group (COG) trials include: (i) superior event-free survival with the addition of brentuximab vedotin (Bv) in frontline regimens for high-risk disease, (ii) successful reduction in myeloablative regimens with demonstrated safety and efficacy of Bv and checkpoint inhibitor therapy in relapsed disease, and (ii) the potential to select a population that can be salvaged after relapse without receiving a stem cell transplant. The COG HL committee will lead a National cancer Institute National Clinical Trials Network phase 3 trial to evaluate the combination of Bv/nivolumab in early-stage disease. Ongoing advances in technology and blood biomarkers are increasing the ability to deliver biologically driven, personalized treatment for HL.

Breast Cancer Screening in Survivors of Childhood Cancer

Women who survived childhood cancers or cancers at a young age are at high risk for breast cancer later in life. The accentuated risk is notable among those treated at a young age with a high radiation dose but also extends to survivors treated with therapies other than or in addition to radiation therapy. The predisposing risk factors are complex. Advances in radiation therapy continue to curtail exposure, yet the risk of a second cancer has no dose threshold and a long latency period, and concurrent use of chemotherapy may have an additive effect on long-term risk of cancer. Early screening with annual mammography and MRI is recommended for chest radiation exposure of 10 Gy or greater, beginning 8 years after treatment or at age 25 years, whichever is later. However, there is a lack of recommendations for those at high risk without a history of radiation therapy. Because mortality after breast cancer among survivors is higher than in women with de novo breast cancer, and because there is a higher incidence of a second asynchronous breast cancer in survivors than that in the general population, regular screening is essential and is expected to improve mortality. However, awareness and continuity of care may be lacking in these young patients and is reflected in their poor screening attendance. The transition of care from childhood to adulthood for survivors requires age-targeted and lifelong strategies of education and risk prevention that are needed to improve long-term outcomes for these patients. ^© RSNA, 2023 See the invited commentary by Chikarmane in this issue. Quiz questions for this article are available through the Online Learning Center.

Diagnosis and management of Hodgkin lymphoma in children, adolescents, and young adults

Advances in the management of Hodgkin lymphoma in children, adolescents and young adult have resulted in survival outcomes exceeding 90%. The risk of late toxicity, however, remains a significant concern for survivors of HL and the focus of modern trials have been to advance cure rates while reducing long term toxicity. This has been accomplished through response-adapted treatment approaches and the incorporation of novel agents, many of which target the unique interaction between the Hodgkin and Reed Sternberg cells and the tumor microenvironment. In addition, an improved understanding of prognostic markers, risk stratification, and the biology of this entity in children and AYAs may allow us to further tailor therapy. This review focuses on the current management of HL in the upfront and relapsed settings, recent advances in novel agents that target HL and the tumor microenvironment, and promising prognostic markers that may help guide the future management of HL.

Targeted radiotherapy for early-stage, low-risk pediatric Hodgkin lymphoma slow early responders: a COG AHOD0431 analysis

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.