Current approaches in the management of low risk Hodgkin lymphoma in children and adolescents

Harnessing multi-source data for individualized care in Hodgkin Lymphoma

Hodgkin lymphoma is a rare, but highly curative form of cancer, primarily afflicting adolescents and young adults. Despite multiple seminal trials over the past twenty years, there is no single consensus-based treatment approach beyond use of multi-agency chemotherapy with curative intent. The use of radiation continues to be debated in early-stage disease, as part of combined modality treatment, as well as in salvage, as an important form of consolidation. While short-term disease outcomes have varied little across these different approaches across both early and advanced stage disease, the potential risk of severe, longer-term risk has varied considerably. Over the past decade novel therapeutics have been employed in the retrieval setting in preparation to and as consolidation after autologous stem cell transplant. More recently, these novel therapeutics have moved to the frontline setting, initially compared to standard-of-care treatment and later in a direct head-to-head comparison combined with multi-agent chemotherapy. In 2018, we established the HoLISTIC Consortium, bringing together disease and methods experts to develop clinical decision models based on individual patient data to guide providers, patients, and caregivers in decision-making. In this review, we detail the steps we followed to create the master database of individual patient data from patients treated over the past 20 years, using principles of data science. We then describe different methodological approaches we are taking to clinical decision making, beginning with clinical prediction tools at the time of diagnosis, to multi-state models, incorporating treatments and their response. Finally, we describe how simulation modeling can be used to estimate risks of late effects, based on cumulative exposure from frontline and salvage treatment. The resultant database and tools employed are dynamic with the expectation that they will be updated as better and more complete information becomes available.

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.

High percentages of peripheral blood T-cell activation in childhood Hodgkin's lymphoma are associated with inferior outcome

The aims of this study were to investigate the activation of T lymphocytes in peripheral blood from children with Hodgkin's lymphoma (HL) and explore their roles for prognosis in HL. A cohort of 52 newly diagnosed children with HL during the past 10 years was enrolled for analysis in this study. Peripheral blood samples of the patients were acquired before treatment in our hospital, and T-cell subsets were detected by a four-color flow cytometer. CD4+ T cells and CD4+/CD8+ T-cell ratio decreased significantly in patients with HL vs. healthy controls. CD8+ T cells, CD3+CD4+HLA-DR+ T cells, and CD3+CD8+HLA-DR+ T cells increased markedly in patients with HL vs. healthy controls. Receiver-operating characteristic (ROC) curve analysis showed that CD3+CD4+HLA-DR+ T cells and CD3+CD8+HLA-DR+ T cells each distinguished the high-risk group from the low- and intermediate-risk group. The area under the ROC curve for predicting high-risk patients was 0.795 for CD3+CD4+HLA-DR+ T cell and 0.784 for CD3+CD8+HLA-DR+ T cell. A comparison of peripheral blood T-cell subsets that responded differently to therapy showed significantly higher percentages of CD3+CD4+HLA-DR+ T cells and CD3+CD8+HLA-DR+ T cells in patients who achieved complete remission compared to those who did not achieve complete remission. In addition, high percentages of both CD3+CD4+HLA-DR+ T cells and CD3+CD8+HLA-DR+ T cells were associated with inferior event-free survival. Peripheral immune status may be related to disease severity in HL. CD3+CD4+HLA-DR+ T cells and CD3+CD8+HLA-DR+ T cells may be a novel indicator for risk stratification of HL and may be an independent risk factor for inferior outcome in childhood HL.

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.

Cardiotoxicity in pediatric lymphoma survivors

INTRODUCTION

Over the past five decades, the diagnosis and management of children with various malignancies have improved tremendously. As a result, an increasing number of children are long-term cancer survivors. With improved survival, however, has come an increased risk of treatment-related cardiovascular complications that can appear decades later.

AREAS COVERED

This review discusses the pathophysiology, epidemiology and effects of treatment-related cardiovascular complications from anthracyclines and radiotherapy in pediatric lymphoma survivors. There is a paucity of evidence-based recommendations for screening for and treatment of cancer therapy-induced cardiovascular complications. We discuss current preventive measures and strategies for their treatment.

EXPERT OPINION

Significant cardiac adverse effects occur due to radiation and chemotherapy received by patients treated for lymphoma. Higher lifetime cumulative doses, female sex, longer follow-up, younger age, and preexisting cardiovascular disease are associated with a higher incidence of cardiotoxicity. With deeper understanding of the mechanisms of these adverse cardiac effects and identification of driver mutations causing these effects, personalized cancer therapy to limit cardiotoxic effects while ensuring an adequate anti-neoplastic effect would be ideal. In the meantime, expanding the use of cardioprotective agents with the best evidence such as dexrazoxane should be encouraged and further studied.

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

Survivors of Hodgkin lymphoma (HL) have an increased risk of subsequent malignant neoplasms (SMNs). Response-adapted treatment may decrease this risk by reducing exposure to therapy associated with SMN risk. The Children's Oncology Group study AHOD0031 evaluated response-adapted therapy for children and adolescents with intermediate-risk HL. We report the SMNs among 1711 patients enrolled in AHOD0031. Patients were treated with 4 cycles of doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide with or without involved-field radiation therapy (RT). Patients with a slow early response to initial chemotherapy were randomized to 2 additional cycles of dexamethasone, etoposide, cisplatin and cytarabine or no additional chemotherapy, and all received RT. At a median follow-up of 7.3 years, an analysis of SMNs was performed. The 10-year cumulative incidence of SMN was 1.3% (95% confidence interval [CI], 0.6-2.0). SMNs included 3 patients with acute myeloid leukemia (AML), 11 with solid tumors, and 3 with non-Hodgkin lymphoma. Sixteen of 17 patients with an SMN had received combined modality therapy. The standardized incidence ratio for SMN was 9.5 (95% CI, 4.5-15.2) with an excess absolute risk of 1.2 per 1000 person-years. The cumulative incidence of SMNs was higher among patients who received RT (P = .037). In multivariate analysis, RT, B symptoms, and race were associated with SMN risk. Given the latency from exposure, we have likely captured all cases of secondary leukemia and myelodysplastic syndrome (MDS). Longer follow-up is needed to determine the risk of solid tumors. Avoidance of RT without sacrificing disease control should remain a goal for future therapeutic approaches. This trial was registered at www.clinicaltrials.gov as #NCT00025259.

AYA Considerations for Aggressive Lymphomas

PURPOSE OF REVIEW

Lymphoma is the one of the most common cancer diagnoses among adolescents and young adults (AYAs) aged 15-39. Despite significant advances in outcomes observed in older adults and younger children, improvements in AYAs have lagged behind. The reasons for this are likely multifactorial including disparities in access to health insurance, low rates of enrollment to clinical trials, potential differences in disease biology, and unique psychosocial challenges. Here we will review Hodgkin lymphoma (HL) and primary mediastinal B cell lymphoma (PMBCL), two of the most common aggressive lymphomas that occur in AYAs. We will discuss the current knowledge about disease biology in AYAs, adult and pediatric treatment strategies, novel targeted therapies, and ongoing AYA clinical trials in these lymphoma subtypes. We also will review unique considerations for treatment-related toxicities in AYAs and psychosocial issues relevant to this population.

RECENT FINDINGS

Pediatric and adult trials in HL and PMBCL have demonstrated that treatment with dose-intense chemotherapeutic regimens with or without radiation results in high cure rates but can also be associated with long-term toxicity which must be considered in this young population. Novel targeted agents such as the antibody-drug conjugate brentuximab vedotin and/or antibodies targeted against PD-1/PD-L1 have demonstrated activity in the relapsed setting and are currently being evaluated in the upfront setting, which may reduce our reliance on therapies associated with long-term toxicity. AYA-focused clinical trials are currently underway to better elucidate the optimal therapy for lymphomas in this age group. There is an urgent need for clinical trials including AYAs in order to increase the knowledge of age-specific outcomes, toxicities, disease biology, and the need to develop comprehensive AYA care models that meet the unique and complex care needs of this patient population.

Hodgkin Lymphoma in Children and Adolescents: Advances in Pathology, Diagnosis, and Treatment Strategies

Strategies used for the treatment of children with Hodgkin lymphoma (HL) over the last four decades have resulted in excellent long-term survivals. However, the short- and long-term treatment-associated morbidities were high. In an attempt to reduce complications, the current treatment strategies apply initial risk stratification principles based on certain host and tumor risk factors to help assign patients to the appropriate risk group and tailor therapy based on response to chemotherapy (CTR). Radiotherapy (RT) was only given to certain groups of patients who show suboptimal response to CTR. Enrollment of patients in clinical trials allowed testing newer treatment strategies, which has improved the outcome significantly. High-dose CTR with stem cell support remains the mainstay of treatment for relapsed and refractory HL. Newer targeted medications are being increasingly used for the treatment of patients with relapsed and refractory HL, but results are variable. In this review report, we give extensive account about the pathophysiology, clinical presentation, histopathological diagnosis, modern investigation techniques, the most recent risk adapted treatment strategies, and the use and effect of novel medications. In addition, we discuss in details the short- and long-term therapy-related complications and future prospects in the management of HL.

Association of Combined Modality Therapy vs Chemotherapy Alone With Overall Survival in Early-Stage Pediatric Hodgkin Lymphoma

Importance

To date, there is no well-defined standard of care for early-stage pediatric Hodgkin lymphoma (HL), which may include chemotherapy alone or combined modality therapy (CMT) with chemotherapy followed by radiotherapy. Although the use of radiotherapy in pediatric HL is decreasing, this strategy remains controversial.

Objective

To examine the use of CMT in pediatric HL and its association with improved overall survival using data from a large cancer registry.

Design, Setting, and Participants

This observational cohort study used data from the National Cancer Database to evaluate clinical features and survival outcomes among 5657 pediatric patients (age, 0.1-21 years) who received a diagnosis of stage I or II HL in the United States from January 1, 2004, to December 31, 2015. Statistical analysis was conducted from May 1 to November 1, 2018.

Exposures

Patients received definitive treatment with chemotherapy or CMT, defined as chemotherapy followed by radiotherapy.

Main Outcomes and Measures

Kaplan-Meier survival curves were used to examine overall survival. The association between CMT use, covariables, and overall survival was assessed in multivariable Cox proportional hazards regression models. Use of radiotherapy was assessed over time.

Results

Among the 11 546 pediatric patients with HL in the National Cancer Database, 5657 patients (3004 females, 2596 males, and 57 missing information on sex; mean [SD] age, 17.1 [3.6] years) with stage I or II classic HL were analyzed. Of these patients, 2845 (50.3%) received CMT; use of CMT vs chemotherapy alone was associated with younger age (<16 years, 1102 of 2845 [38.7%] vs 856 of 2812 [30.4%]; P < .001), male sex (1369 of 2845 [48.1%] vs 1227 of 2812 [43.6%]; P < .001), stage II disease (2467 of 2845 [86.7%] vs 2376 of 2812 [84.5%]; P = .02), and private health insurance (2065 of 2845 [72.6%] vs 1949 of 2812 [69.3%]; P = .002). The 5-year overall survival was 94.5% (confidence limits, 93.8%, 95.8%) for patients who received chemotherapy alone and 97.3% (confidence limits, 96.4%, 97.9%) for those who received CMT, which remained significant in the intention-to-treat analysis and multivariate analysis (adjusted hazard ratio for CMT, 0.57; 95% CI, 0.42-0.78; P < .001). In the sensitivity analysis, the low-risk cohort (stage I-IIA) and adolescent and young adult patients had the greatest benefit from CMT (adjusted hazard ratio, 0.47; 95% CI, 0.40-0.56; P < .001). The use of CMT decreased by 24.8% from 2004 to 2015 (from 59.7% [271 of 454] to 34.9% [153 of 438]).

Conclusions and Relevance

In this study, pediatric patients with early-stage HL receiving CMT experienced improved overall survival 5 years after treatment. There is a nationwide decrease in the use of CMT, perhaps reflecting the bias of ongoing clinical trials designed to avoid consolidation radiotherapy. This study represents the largest data set to date examining the role of CMT in pediatric HL.

Surveillance imaging in pediatric lymphoma

Current therapies used in treating children with Hodgkin lymphoma and many histological subtypes of non-Hodgkin lymphoma have resulted in overall survival rates exceeding 90% in many instances. With increasing concerns related to the cost of radiologic imaging, exposure to ionizing radiation, and potential false-positive results, the role of routine off-therapy surveillance imaging has been called into question. Although radiologic imaging plays an important role in diagnosing and assessing treatment response, in these children - the majority of whom have an excellent outcome following completion of therapy - there is an opportunity to dramatically reduce the number of off-therapy imaging evaluations. This review summarizes several recent studies in both Hodgkin and non-Hodgkin lymphoma providing evidence to support these efforts. In addition, we propose a surveillance imaging strategy that uses a novel risk-adapted and response-based approach to determine which children would most benefit from off-therapy imaging surveillance.

Early-stage Hodgkin lymphoma in the modern era: simulation modelling to delineate long-term patient outcomes

We developed a novel simulation model integrating multiple data sets to project long-term outcomes with contemporary therapy for early-stage Hodgkin lymphoma (ESHL), namely combined modality therapy (CMT) versus chemotherapy alone (CA) via ¹⁸ F-fluorodeoxyglucose positron emission tomography response-adaption. The model incorporated 3-year progression-free survival (PFS), probability of cure with/without relapse, frequency of severe late effects (LEs), and 35-year probability of LEs. Furthermore, we generated estimates for quality-adjusted life years (QALYs) and unadjusted survival (life years, LY) and used model projections to compare outcomes for CMTversusCA for two index patients. Patient 1: a 25-year-old male with favourable ESHL (stage IA); Patient 2: a 25-year-old female with unfavourable ESHL (stage IIB). Sensitivity analyses assessed the impact of alternative assumptions for LE probabilities. For Patient 1, CMT was superior to CA (CMT incremental gain = 0·11 QALYs, 0·21 LYs). For Patient 2, CA was superior to CMT (CA incremental gain = 0·37 QALYs, 0·92 LYs). For Patient 1, the advantage of CMT changed minimally when the proportion of severe LEs was reduced from 20% to 5% (0·15 QALYs, 0·43 LYs), whereas increasing the severity proportion for Patient 2's LEs from 20% to 80% enhanced the advantage of CA (1·1 QALYs, 6·5 LYs). Collectively, this detailed simulation model quantified the long-term impact that varied host factors and alternative contemporary treatments have in ESHL.

ABVD-Based Therapy for Hodgkin Lymphoma in Children and Adolescents: Lessons Learnt in a Tertiary Care Oncology Center in a Developing Country

BACKGROUND

As Hodgkin lymphoma (HL) is a highly curable malignancy, most current pediatric trials focus on strategies aimed at reducing late effects of therapy. We report our results with doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) therapy.

PROCEDURE

We retrospectively analyzed 17 years (1996-2013) data of patients ≤18 years of age with HL. All patients received ABVD chemotherapy and involved field radiotherapy (IFRT) was reserved for those with bulky disease or partial response. The analysis was carried out to assess overall survival (OS) and freedom from treatment failure (FFTF) and factors predicting the events.

RESULTS

Of 167 eligible patients, 72 (43.1%) had B symptoms, 28 (16.7%) had bulky disease, 31 (18.6%) had >4 lymph node regions, and 53 (31.8%) had advanced disease (stages III and IV). In all, 87% patients received six cycles of ABVD and IFRT was administered to 51 (30.5%) patients. The 5-year OS and FFTF were 95.9% and 79%, respectively, and were similar in patients treated with or without IFRT. On multivariable analysis, advanced disease (stages III and IV), involvement of >4 lymph node regions, and serum lactate dehydrogenase (LDH) ≥500 IU/l at diagnosis were statistically significant factors for FFTF (P = 0.03, 0.003, 0.048, respectively).

CONCLUSIONS

The excellent survival of HL patients in the setting of a developing country reported in this retrospective analysis warrants treatment reduction, especially for early-stage patients. The use of risk- and response-based stratification incorporating disease stage, involved lymph node regions, and serum LDH, along with fluorodeoxyglucose-positron emission tomography-based response, may guide development of effective and less toxic protocols.

Involved site radiation therapy for the treatment of early-stage Hodgkin lymphoma in adolescents and young adults

Radiation therapy technology has permitted the development of new treatment planning techniques. Involved field, involved node, and involved site radiotherapy fields are discussed and compared. Indications for and implications of combined modality therapy are examined, particularly as pertinent to the adolescent and young adult population.