Characteristics of relapsed and refractory paediatric Hodgkin lymphoma; a 10-year retrospective study of an LMIC

Background

With conventional standard treatment modalities, children and adolescents with Hodgkin lymphoma (HL) have long-term overall survival rates of over 90%. However, primary refractory disease may occur in 5%-10% of HL patients, while relapse occurs in 5%-10% of patients with early stage disease and up to 30% in an advanced stage. This retrospective study evaluated patient characteristics in cases of HL relapse and refractory and their response to second-line treatment of standalone chemotherapy or in combination with radiotherapy.

Methodology

A retrospective study was conducted by Indus Hospital and Health Network to determine the outcomes of paediatric patients with first and second relapses of HL between 2013 and 2022.

Results

A total of 742 patients were diagnosed with HL at Indus Hospital & Health Network. Of these, 48 (6.5%) patients presented with relapse and 35 (4.7%) with refractory disease after initial chemotherapy. In HL relapse patients, 57% were stage IV at initial diagnosis with the most common pathology being nodular sclerosis constituting 42.9% of patients. The most common age group was 6-10 years, 45.8%. B symptoms were experienced by 25 (52%) patients. A time to relapse of >12 months following diagnosis was seen in 69% and 3-12 months was seen in 31%.After receiving second-line treatment, complete remission was achieved by 34 (70.8%) patients, partial remission (PR) was seen in 5 (10.4%), disease progression in 5 (10.4%), 3 (6.3%) patients left during treatment and 1 (2.1%) had a treatment-related mortality. Re-radiation in second-line treatment was only required for 2 patients. The second relapse was seen in 11 (28.2%) of 39 complete and PR patients.

Conclusion

Major limitations in the treatment of HL relapse in a low-resource setting are the non-availability of immunotherapy and autologous stem cell transplantation due to extreme financial burden and lack of capacity in facilities. Dedicated efforts are required to provide these facilities free of cost in low-middle income countries (LMICs).

Brentuximab vedotin after autologous transplantation in pediatric patients with relapsed/refractory Hodgkin lymphoma

Outcomes for children and adolescents with relapsed and refractory Hodgkin lymphoma (HL) are poor, with ∼50% of patients experiencing a subsequent relapse. The anti-CD30 antibody-drug conjugate brentuximab vedotin improved progression-free survival (PFS) when used as consolidation after autologous stem cell transplantation (ASCT) in adults with high-risk relapsed/refractory HL. Data on brentuximab vedotin as consolidative therapy after ASCT in pediatric patients with HL are extremely limited, with data of only 11 patients reported in the literature. We performed a retrospective analysis of 67 pediatric patients who received brentuximab vedotin as consolidation therapy after ASCT for the treatment of relapsed/refractory HL to describe the experience of this regimen in the pediatric population. This is the largest cohort reported to date. We found that brentuximab vedotin was well tolerated with a safety profile similar to that of adult patients. With a median follow-up of 37 months, the 3-year PFS was 85%. These data suggest a potential role for the use of brentuximab vedotin as consolidation therapy after ASCT for children with relapsed/refractory HL.

Outcome and toxicity of ifosfamide, carboplatin, and etoposide versus gemcitabine and vinorelbine regimen for pediatric patients with relapsed or refractory Hodgkin's lymphoma

Background

Pediatric classical Hodgkin lymphoma (CHL) is a curable disease; however, the optimal salvage regimen is unclear for relapsed/refractory (R/R) disease. This study aimed to compare response rates, toxicity, event-free survival (EFS), and overall survival (OS) of ifosfamide, carboplatin, and etoposide (ICE) with gemcitabine and vinorelbine (GV) regimen after first-line doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) in pediatric patients with R/R CHL.

Methods

This is a retrospective cohort study of 132 pediatric patients with R/R CHL treated from July 2012 to December 2020 with ICE (n = 82) or GV (n = 50).

Results

The median age at relapse was 13.9 years, and 68.2% were men. Rates of complete response, partial response, and progressive disease before consolidation were 50.6%, 3.7%, and 45.7% for ICE and 28.5%, 0%, and 71.5% for GV (P = 0.011). By multivariate analysis, regimen (P = 0.002), time to relapse (P = 0.0001), and B-symptoms (P = 0.002) were independent factors to lower response rates. Hematological toxicity, electrolyte disturbance, hemorrhagic cystitis, infectious complications, and hospital admission for fever neutropenia were statistically significant higher for the ICE regimen. Treatment-related mortalities were 2.4% for ICE and 2% for GV (P = 0.86). The 3-year EFS was 39.3% ± 11.4% for ICE and 24.9% ± 12.5% for GV (P = 0.0001), while 3-year OS was 69.3% ± 10.6% and 74% ± 12.9% (P = 0.3), respectively. By multivariate analysis, regimen (P = 0.0001), time to relapse (P = 0.011), B-symptoms (P = 0.001), and leukocytosis (P = 0.007) were significant for EFS, while anemia (P = 0.008), and progressive disease on early response evaluation (P = 0.022) were significant for OS.

Conclusions

The ICE regimen had a better overall response rate and EFS, but higher toxicity, than GV; however, OS and mortality were similar.

Defining the Inflammatory Plasma Proteome in Pediatric Hodgkin Lymphoma

Simple Summary

Hodgkin lymphoma (HL) is a common type of cancer that is characterized by rare, malignant cells among an inflammatory microenvironment. Specific systemic, inflammatory plasma proteins have demonstrated prognostic significance in adult HL; however, systemic inflammation has not been well-characterized in childhood HL. The aim of our study was to better define the inflammatory pre-therapy plasma proteome and identify plasma proteins associated with clinical features of childhood HL. We measured plasma concentrations of 135 proteins in 56 pediatric subjects with newly diagnosed HL and 47 healthy pediatric controls. We found that the plasma protein profile was distinct from controls, and unique proteins were associated with high-risk disease (IL-10, TNF-α, IFN-γ, IL-8), slow early therapy response (CCL13, IFN-λ1, IL-8), and relapse (TNFSF10). These proteins could be used to improve risk stratification, and thus optimize outcomes and minimize unnecessary toxic exposures for those with childhood HL.

Abstract

Hodgkin lymphoma (HL) histopathology is characterized by rare malignant Reed–Sternberg cells among an inflammatory infiltrate. We hypothesized that characteristics of inflammation in pediatric HL lesions would be reflected by the levels of inflammatory cytokines or chemokines in pre-therapy plasma of children with HL. The study objectives were to better define the inflammatory pre-therapy plasma proteome and identify plasma biomarkers associated with extent of disease and clinical outcomes in pediatric HL. Pre-therapy plasma samples were obtained from pediatric subjects with newly diagnosed HL and healthy pediatric controls. Plasma concentrations of 135 cytokines/chemokines were measured with the Luminex platform. Associations between protein concentration and disease characteristics were determined using multivariate permutation tests with false discovery control. Fifty-six subjects with HL (mean age: 13 years, range 3–18) and 47 controls were analyzed. The cytokine/chemokine profiles of subjects with HL were distinct from controls, and unique cytokines/chemokines were associated with high-risk disease (IL-10, TNF-α, IFN-γ, IL-8) and slow early response (CCL13, IFN-λ1, IL-8). TNFSF10 was significantly elevated among those who ultimately relapsed and was significantly associated with worse event-free survival. These biomarkers could be incorporated into biologically based risk stratification to optimize outcomes and minimize toxicities in pediatric HL.

Response rates, long term outcomes and toxicity profile of gemcitabine and vinorelbine based outpatient chemotherapy regimen in primary progressive and relapsed childhood Hodgkin lymphoma

This study aimed to determine response rates, overall survival (OS), event-free survival (EFS) and toxicity profile of an outpatient chemotherapy regimen based on gemcitabine and vinorelbine (GV) for relapsed childhood Hodgkin lymphoma (HL). This was a retrospective study that included 41 patients up to the age of 18 years with relapsed HL. Twelve patients (29%) had primary progressive disease (PPD), 6 (15%) had early relapse (ER) and 23 (56%) had late relapse (LR). The overall initial response rate was 83% (LR: 87%, ER: 83%, PPD: 75%. p-value: .2). Three-year combined OS was 80% (LR: 89%, ER: 80%, PPD: 65%. p-value: .07) and EFS 71% (LR: 86%, ER: 62%, PPD: 47%. p-value: .01). There were no toxic deaths. Febrile neutropenia was observed in four patients (9.6%) and lung toxicity in 1 patient (2.4%). This study suggests that outpatient GV is an effective and low toxicity salvage regimen for relapsed childhood HL.

Outcomes of Refractory and Relapsed Hodgkin Lymphoma With Autologous Stem-Cell Transplantation: A Single Institution Experience

PURPOSE

Hodgkin lymphoma is the most common cancer in children, adolescents, and young adults. Overall survival is approximately 80% to 90%. A subset of these patients has refractory disease or experience disease relapse. Conventional salvage therapies and autologous stem-cell transplantation is usually considered the standard of care for these patients. Our analysis reports outcomes in these patients.

PATIENTS AND METHODS

After institutional review board approval, a retrospective analysis of patients with Hodgkin lymphoma who were up to 18 years of age and who had refractory or relapsed disease at Shaukat Khanum Memorial Cancer Hospital and Research Centre from September 2009 to December 2013 was performed. Patients who underwent high-dose chemotherapy followed by stem-cell rescue were included in this analysis.

RESULTS

A total of 567 patients with Hodgkin lymphoma registered at the hospital. Sixty of the patients (10.6%) had either primary progressive or refractory disease or relapse after finishing with first-line chemotherapy. High-dose chemotherapy followed by stem cell was administered to 25 of these patients (42%). Thirteen patients (40%) had progressive disease (PD), five (22%) had early relapse, and seven (38%) had late relapse. A number of salvage regimens were used, including etoposide, prednisolone, ifosfamide, and cisplatin; dexamethasone, cytarabine, and carboplatin; and gemcitabine plus vinorelbine. Re-evaluation was performed before taking patients to a high dose, and it showed complete response in 17 patients (68%), partial response in six patients (24%), and PD in two patients (8%). Twenty-one patients (84%) are in remission after transplantation, with two patients (8%) having died as a result of disease progression and two patients (2%) having relapsed after treatment. Overall survival is 92% at 4 years, with event-free survival of 80% at 4 years.

CONCLUSION

Our retrospective analysis shows good outcomes in patients who had PD or refractory disease. Disease response before transplantation is important in predicting outcomes.

Autologous hematopoietic cell transplantation for the treatment of relapsed/refractory pediatric, adolescent, and young adult Hodgkin lymphoma: a single institutional experience

Pediatric, adolescent, and young adult patients with relapsed or refractory Hodgkin lymphoma receive multimodal therapy, including autologous hematopoietic cell transplantation (AutoHCT). Despite aggressive therapy, historical outcomes for this patient population have been poor. This paper describes a single institutional experience utilizing AutoHCT in 74 patients treated from 1988-2015. Our results demonstrate significantly improved outcomes over time. Compared with patients treated in the earlier era (1988-2001), 5-year overall survival improved from 62.5 ± 9.6% to 91.8 ± 4.4% (p < 0.001) and event free survival improved from 41.7 ± 9.6% to 87.7 ± 5.3% (I < 0.001) for patients treated in a later era (2002-2015). Improvements in survival are multifactorial, including reductions in both relapse and nonrelapse mortality. Further investigation is needed to determine the role of AutoHCT in a modern treatment cohort that includes frequent use of targeted immunotherapies. In addition, as the use and availability of effective novel therapeutics increases for this patient population there may be an opportunity for the reduction of standard cytotoxic therapies, including in AutoHCT preparative regimens, thereby mitigating late effects.

Risk and Response Adapted Treatment Guidelines for Managing First Relapsed and Refractory Classical Hodgkin Lymphoma in Children and Young People. Recommendations from the EuroNet Pediatric Hodgkin Lymphoma Group

The objective of this guideline is to aid clinicians in making individual salvage treatment plans for pediatric and adolescent patients with first relapse or refractory (R/R) classical Hodgkin lymphoma (cHL). While salvage with standard dose chemotherapy followed by high dose chemotherapy and autologous stem cell transplant is often considered the standard of care in adult practice, pediatric practice adopts a more individualized risk stratified and response adapted approach to salvage treatment with greater use of non-transplant salvage. Here, we present on behalf of the EuroNet Pediatric Hodgkin Lymphoma group, evidence and consensus-based guidelines for standardized diagnostic, prognostic and response procedures to allocate children and adolescents with R/R cHL to stratified salvage treatments.

Outcome predictors of autologous hematopoietic stem cell transplantation in children with relapsed and refractory Hodgkin lymphoma: Single-center experience in a lower-middle-income country

BACKGROUND

Children and adolescents with HL have excellent long-term survival exceeding 95% after combined modality treatment. However, about 20% will either relapse or have PRF. Salvage HDCT followed by AHSCT is considered to be the preferential treatment.

OBJECTIVE

To describe the outcome (OS and EFS) and prognostic factors in pediatric patients with relapsed or refractory HL (r/rHL) who underwent AHSCT.

METHODS

We retrospectively included 43 pediatric patients with r/rHL who underwent AHSCT from July 1, 2007, till December 31, 2016, at the Children's Cancer Hospital of Egypt. MAC regimen given was CMV.

RESULTS

Of the whole cohort, 88.4% of patients achieved CR, while 11.6% had a positive PET scan prior to transplantation. The 3-year OS and EFS were 85% and 70.6%, respectively. The 3-year OS for patients > 10 years was 94% versus 65.5% for patients 10 years of age or younger (P = 0.046). There is strong tendency toward better 3-year OS for patients with negative PET scan as compared to those with positive PET scan before AHSCT, 89.4% vs 60%, respectively (P = 0.059). This tendency is also applicable when looking at the 3-year EFS for the two groups, 78.3% vs 40%, respectively (P = 0.069).

CONCLUSION

Poor predictors of OS were younger age and positive PET scan before AHSCT. The latter, along with single modality treatment before AHSCT, were poor predictors of EFS.

Pretransplant functional imaging and outcome in pediatric patients with relapsed/refractory Hodgkin lymphoma undergoing autologous transplantation

BACKGROUND

Pretransplant functional imaging (FI), particularly a negative positron emission tomography (PET), is a strong predictor of outcome in adults with relapsed or refractory Hodgkin lymphoma (HL), but data in pediatrics are limited.

METHODS

The medical records of 49 consecutive pediatric patients, who received autologous transplant at a single institution, were retrospectively analyzed. All patients had either gallium or PET scan before transplant and were conditioned with carmustine, etoposide, cytarabine, and melphalan (BEAM). Deauville scores were retrospectively assigned for patients with PET (score ≥ 4 positive).

RESULTS

Of the 49 patients (median age, 16.2 years), 41 (84%) were pretransplant FI negative and eight (16%) were pretransplant FI positive, after first- to fourth-line salvage therapy, and a median of two salvage cycles. Eighteen patients (37%) received posttransplant radiation. At a median follow up of 46 months, 45 patients (92%) were alive and disease free, and there were three nonrelapse deaths and only one relapse death (Deauville score of 5). The 4-year progression-free survival (PFS) for the entire cohort was 92% (95% confidence interval [CI]: 78-97), and PFS based on pretransplant disease status was 95% (95% CI: 82-99%) in the negative FI group versus 75% (95% CI: 31-93) if positive FI (P = 0.057).

CONCLUSION

Our analysis revealed outstanding outcomes for children and adolescents with relapsed/refractory HL. There were too few relapses to identify the predictive value of pretransplant metabolic status, but pediatric patients with relapsed/refractory HL and a negative pretransplant FI had excellent survival.

Management of Hodgkins Lymphoma: ICMR Consensus Document

Pediatric Hodgkins lymphoma is a highly curable disease even in the developing world. Current treatment paradigms follow a risk and response based approach. The goal is to minimise treatment related short and long-term toxicity while maintaining excellent survival. A confirmed histopathological diagnosis and full staging work-up are essential prior to embarking on treatment and guidelines for these are provided in the text. All patients require combination chemotherapy while radiotherapy is usually reserved for a select subgroup depending on the protocol used. It is important to follow these patients for relapse in the first five years and life-long for late effects as most of them will be cured.

Outcome analysis of high-dose chemotherapy and autologous stem cell transplantation in adolescent and young adults with relapsed or refractory Hodgkin lymphoma

High-dose chemotherapy (HDC) and autologous stem cell transplantation (auto-SCT) can salvage many patients with relapsed or refractory Hodgkin's lymphoma (HL). We are reporting the outcome of HDC auto-SCT and the impact of 21 prognostic factors in relapsed and refractory adolescent (14-21 years) and young adult (>21-30 years) (AYA) HL patients. We used Fine and Gray's competing risk analysis method and regression model for outcome analysis. From 1996 to 2013, 290 consecutive patients with biopsy-proven HL underwent HDC auto-SCT for relapsed/refractory HL; 216 patients (74.5 %) were AYA at the time of auto-SCT. Male/female were equal, median age at auto-SCT was 22.4 years, and there were 94 adolescent (43.5 %) and 122 young adults (56.5 %). There was refractory disease in 121 (56 %) patients, relapsed in 95 (44 %). Median follow-up was 72.6 months. The Kaplan-Meier method estimated that 5-year overall survival is 62.7 % (adolescents (63.5 %), young adults (62 %)) and event-free survival was 51.3 %. Five-year cumulative incidence of disease-specific death (DS-death) is 33 % and that of DS-event is 45 %. For DS-death, the multivariate analysis identified complete remission (CR) duration of <12 months (hazard ratio (HR) 3.61, P = 0.0009), no CR after salvage (HR: 3.93, P = 0.0002), and nodular sclerosis pathology (HR 3.3, P = 0.016) and positive B symptoms (HR 2, P = 0.028) as negative factors. For DS-event, CR duration of <12 months (HR 1.88, P = 0.02), no CR after salvage (HR 3.47, P = 0.000005) and nodular sclerosis pathology (HR 1.88, P = 0.02) were found significant. The Kaplan-Meier method estimated overall survival (OS) at 36 months with 0-2:3:4 factors being 93.6:54:21 %, respectively (P value <0.001). Kaplan-Meier estimated event-free survival (EFS) at 36 months with 0-1:2:3 factors being 84.6:65:31 %, respectively (P value <0.001). Clinically, adolescents have similar outcomes as young adults.

Antibody therapies for lymphoma in children

BACKGROUND

Lymphomas are the third most common malignancy in childhood. Cure rates are high but have reached a plateau. Therefore new treatment modalities should be developed. Antibody therapy is a successful new treatment option in adult lymphoma. However, none of the therapeutic antibodies available for adults with cancer have been approved for treatment of paediatric lymphoma.

OBJECTIVES

To assess the efficacy of antibody therapy for childhood lymphoma in terms of survival, response and relapse rates, compared with therapy not including antibody treatment. To assess quality of life and the occurrence of adverse effects caused by antibody therapy treatment in children compared with therapy not including antibody treatment.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, 2014, Issue 10), MEDLINE in PubMed (from 1945 to October 2014), EMBASE in EMBASE.com (from 1980 to October 2014) and reference lists of relevant articles. Furthermore, we searched conference proceedings abstracts of SIOP, ASCO and ASH for studies from 2009 to 2013), and the World Health Organization (WHO) ICTRP portal and ClinicalTrials.gov for ongoing trials.

SELECTION CRITERIA

Randomised controlled trials and controlled clinical trials comparing conventional therapy with antibody therapy in children with lymphoma.

DATA COLLECTION AND ANALYSIS

Two authors independently performed the study selection.

MAIN RESULTS

We found no studies meeting the inclusion criteria of the review.

AUTHORS' CONCLUSIONS

At this moment, it is not possible to draw evidence-based conclusions regarding clinical practice. Phase I and II studies show a positive effect of using antibody therapy in childhood lymphoma. Further research is needed to evaluate and implement antibody therapy for paediatric lymphoma.

A prognostic model predicting autologous transplantation outcomes in children, adolescents and young adults with Hodgkin lymphoma

Autologous hematopoietic cell transplantation (AutoHCT) is a potentially curative treatment modality for relapsed/refractory Hodgkin lymphoma (HL). However, no large studies have evaluated pre-transplant factors predictive of outcomes of AutoHCT in children, adolescents and young adults (CAYA, age <30 years). In a retrospective study, we analyzed 606 CAYA patients (median age 23 years) with relapsed/refractory HL who underwent AutoHCT between 1995–2010. The probabilities of progression free survival (PFS) at 1, 5 and 10 years were 66% (95% CI: 62–70), 52% (95% CI: 48–57) and 47% (95% CI: 42–51), respectively. Multivariate analysis for PFS demonstrated that at the time of AutoHCT patients with Karnofsky/Lansky score ≥90, no extranodal involvement and chemosensitive disease had significantly improved PFS. Patients with time from diagnosis to first relapse of <1 year had a significantly inferior PFS. A prognostic model for PFS was developed that stratified patients into low, intermediate and high-risk groups, predicting for 5-year PFS probabilities of 72% (95% CI: 64–80), 53% (95% CI: 47–59) and 23% (95% CI: 9–36), respectively. This large study identifies a group of CAYA patients with relapsed/refractory HL who are at high risk for progression after AutoHCT. Such patients should be targeted for novel therapeutic and/or maintenance approaches post-AutoHCT.

Bone Marrow Gene Therapy for HIV/AIDS

Bone marrow gene therapy remains an attractive option for treating chronic immunological diseases, including acquired immunodeficiency syndrome (AIDS) caused by human immunodeficiency virus (HIV). This technology combines the differentiation and expansion capacity of hematopoietic stem cells (HSCs) with long-term expression of therapeutic transgenes using integrating vectors. In this review we summarize the potential of bone marrow gene therapy for the treatment of HIV/AIDS. A broad range of antiviral strategies are discussed, with a particular focus on RNA-based therapies. The idea is to develop a durable gene therapy that lasts the life span of the infected individual, thus contrasting with daily drug regimens to suppress the virus. Different approaches have been proposed to target either the virus or cellular genes encoding co-factors that support virus replication. Some of these therapies have been tested in clinical trials, providing proof of principle that gene therapy is a safe option for treating HIV/AIDS. In this review several topics are discussed, ranging from the selection of the antiviral molecule and the viral target to the optimal vector system for gene delivery and the setup of appropriate preclinical test systems. The molecular mechanisms used to formulate a cure for HIV infection are described, including the latest antiviral strategies and their therapeutic applications. Finally, a potent combination of anti-HIV genes based on our own research program is described.

Beyond PET/CT in Hodgkin lymphoma: a comprehensive review of the role of imaging at initial presentation, during follow-up and for assessment of treatment-related complications

Objective

The purpose of this article is to provide a comprehensive review of the role of imaging modalities other than PET/CT in the management of Hodgkin lymphoma (HL). PET/CT is the imaging modality of choice in the management of Hodgkin’s lymphoma (HL). However, imaging modalities other than PET/CT such as plain radiographs, ultrasound, CT, MRI and nuclear imaging can help in various stages of clinical management of HL, including the initial workup and post-treatment surveillance. Both CT and MRI help in detecting recurrences, treatment-related pulmonary, cardiovascular and abdominal complications as well as second malignancies. Familiarity with expected post-treatment changes and complications on surveillance images can help radiologists guide patient management. The purpose of this article is to provide a comprehensive review of the role of imaging modalities other than PET/CT in the management of Hodgkin lymphoma (HL).

Main Messages

• Surveillance of HL patients is usually performed with plain radiographs and CT.

• Follow-up imaging can depict normal post-treatment changes or treatment-related complications.

• Imaging is important for the timely detection of second malignancies in HL patients.

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

The outcome for children and adolescents with low risk Hodgkin lymphoma (HL) is excellent, with event-free survival >85% and overall survival >95%. Historically, however, treatment has come at the cost of significant long-term toxicity from chemotherapy, radiation or a combination of these. Recent treatment strategies have focused on maintaining high event-free and overall survival while minimizing the use of therapy associated with late effects. The strategies used to achieve this vary greatly among paediatric cooperative groups and there is no one standard treatment for children with low risk HL. This review summaries recent clinical trials in paediatric low risk HL and addresses some of the important considerations when comparing trials, including differences in the definition of low risk HL, differences in outcome among histological subtypes and varying approaches to reduce or eliminate radiation therapy. Recommendations are provided for the treatment of children with low risk HL outside the setting of a clinical trial.

Potential mechanisms for cell-based gene therapy to treat HIV/AIDS

INTRODUCTION

An estimated 35 million people are infected with HIV worldwide. Anti-retroviral therapy (ART) has reduced the morbidity and mortality of HIV-infected patients but efficacy requires strict adherence and the treatment is not curative. Most importantly, the emergence of drug-resistant virus strains and drug toxicity can restrict the long-term therapeutic efficacy in some patients. Therefore, novel treatment strategies that permanently control or eliminate the virus and restore the damaged immune system are required. Gene therapy against HIV infection has been the topic of intense investigations for the last two decades because it can theoretically provide such a durable anti-HIV control.

AREAS COVERED

In this review we discuss two major gene therapy strategies to combat HIV. One approach aims to kill HIV-infected cells and the other is based on the protection of cells from HIV infection. We discuss the underlying molecular mechanisms for candidate approaches to permanently block HIV infection, including the latest strategies and future therapeutic applications.

EXPERT OPINION

Hematopoietic stem cell-based gene therapy for HIV/AIDS may eventually become an alternative for standard ART and should ideally provide a functional cure in which the virus is durably controlled without medication. Recent results from preclinical research and early-stage clinical trials support the feasibility and safety of this novel strategy.

Donor lymphocyte infusion is an effective therapy for relapsed Hodgkin lymphoma after reduced-intensity allogeneic hematopoietic stem cell transplantation

A 3-year-old boy with Hodgkin lymphoma relapsed only 2 months after completion of first-line therapy. He received reduced-intensity conditioning and allogeneic hematopoietic stem cell transplantation (RIC allo-HSCT), but relapsed again. To treat the second relapse, donor lymphocyte infusions were performed four times. He showed no evidence of disease and his quality of life was maintained for 500 days after stem cell transplant. However, his condition worsened and he died 3 years and 3 months after onset. In high-risk patients fully intolerant to myeloablative regimens, RIC allo-HSCT followed by subsequent donor lymphocyte infusions must be considered an effective therapeutic approach.

Sequential myeloablative autologous stem cell transplantation and reduced intensity allogeneic hematopoietic cell transplantation is safe and feasible in children, adolescents and young adults with poor-risk refractory or recurrent Hodgkin and non-Hodgkin lymphoma

The outcome of children, adolescents and young adults (CAYA) with poor-risk recurrent/refractory lymphoma is dismal (⩽30%). To overcome this poor prognosis, we designed an approach to maximize an allogeneic graft vs lymphoma effect in the setting of low disease burden. We conducted a multi-center prospective study of myeloablative conditioning (MAC) and autologous stem cell transplantation (AutoSCT), followed by a reduced intensity conditioning (RIC) and allogeneic hematopoietic cell transplantation (AlloHCT) in CAYA, with poor-risk refractory or recurrent lymphoma. Conditioning for MAC AutoSCT consisted of carmustine/etoposide/cyclophosphamide, RIC consisted of busulfan/fludarabine. Thirty patients, 16 Hodgkin lymphoma (HL) and 14 non-Hodgkin lymphoma (NHL), with a median age of 16 years and median follow-up of 5years, were enrolled. Twenty-three patients completed both MAC AutoSCT and RIC AlloHCT. Allogeneic donor sources included unrelated cord blood (n=9), unrelated donor (n=8) and matched siblings (n=6). The incidence of transplant-related mortality following RIC AlloHCT was only 12%. In patients with HL and NHL, 10 year EFS was 59.8% and 70% (P=0.613), respectively. In summary, this approach is safe, and long-term EFS with this approach is encouraging considering the poor-risk patient characteristics and the use of unrelated donors for RIC AlloHCT in the majority of cases.

Stratification of treatment intensity in relapsed pediatric Hodgkin lymphoma

Risk-adapted, response-based therapies for pediatric Hodgkin lymphoma have resulted in 5-year survival exceeding 90%. Although high-dose chemotherapy and autologous hematopoietic stem cell transplantation (AHSCT) are considered standard for most patients with relapsed or refractory Hodgkin lymphoma, a subset of children with low risk relapse do not require AHSCT for cure. Currently there are no widely accepted criteria defining who should receive standard dose chemotherapy and/or radiotherapy, nor is there a standardized treatment regimen. We propose a risk-stratified, response-based algorithm for children with relapsed or refractory Hodgkin lymphoma that is based on a critical appraisal of published outcomes and prognostic factors.

Treatment outcome in children and adolescents with relapsed Hodgkin lymphoma--results of the UK HD3 relapse treatment strategy

The purpose of this national retrospective study was to evaluate the outcome in children with relapsed or primary refractory Hodgkin lymphoma [HL] after a primary chemotherapy alone treatment strategy. Between 2000 and 2005, 80 children with relapsed [n = 69] or primary refractory [n = 11] HL were treated on a standardized treatment protocol of 4-6 cycles of EPIC [etoposide, prednisolone, ifosfamide and cisplatin] chemotherapy. Radiotherapy was recommended to all relapsed sites. High dose therapy with stem cell rescue [SCT] was recommended for patients with poor response. The 5-year overall survival [OS] and progression-free survival from relapse was 75·8% [64·8-83·9] and 59·9% [48·3-69·7] respectively. Duration of first remission was strongly associated with OS; risk of death was decreased by 53% [Hazard ratio (HR): 0·47, 95% confidence interval (CI): 0·19-1·18] for those with a time from end of treatment to relapse of 3-12 months (compared to <3 months) and reduced by 80% (HR 0·20, 95% CI: 0·04-0·90) for those >12 months after end of treatment. Other poor prognostic factors included advanced stage disease at relapse and B symptoms at first diagnosis. The most important factor associated with salvage failure was time to relapse. Survival outcome in children with primary refractory HL is poor.

Targeted therapy for Hodgkin lymphoma and systemic anaplastic large cell lymphoma: focus on brentuximab vedotin

Despite the relative success of chemotherapy for Hodgkin lymphoma (HL) and systemic anaplastic large cell lymphoma (ALCL), novel therapeutic agents are needed for refractory or relapsed patients. Targeted immunotherapy has emerged as a novel treatment option for these patients. Although unconjugated anti-cluster of differentiation (CD)30 antibodies showed minimal antitumor activity in early clinical trials, development of antibody–drug conjugates (ADCs) appears promising. Brentuximab vedotin is an ADC composed of an anti-CD30 antibody linked to a potent microtubule-disrupting agent monomethyl auristatin E (MMAE). It has the ability to target CD30-positive tumor cells and, once bound to CD30, brentuximab vedotin is internalized and MMAE is released to induce cell cycle arrest and apoptosis. In two Phase II trials, objective response was reported in 75% and 86% of patients with refractory or relapsed HL and systemic ALCL, respectively, with an acceptable toxicity profile. Based on these studies, the US Food and Drug Administration (FDA) granted accelerated approval of brentuximab vedotin in August 2011 for the treatment of refractory and relapsed HL and ALCL. We review the key characteristics of brentuximab vedotin, clinical data supporting its therapeutic efficacy, and current ongoing trials to explore its utility in other CD30-positive malignancies.

The EBV oncogene LMP1 protects lymphoma cells from cell death through the collagen-mediated activation of DDR1

Expression of the EBV oncogene LMP1 in primary human germinal center B cells, upregulates DDR1, a receptor tyrosine kinase activated by collagen Primary HRS cells overexpress DDR1, and its activation significantly increases lymphoma cell survival in vitro

Children's Oncology Group's 2013 blueprint for research: Hodgkin lymphoma

In childhood Hodgkin lymphoma, estimated 5 years survival rates exceed 90%. Long-term survival continues to decline from delayed toxicities. Key findings from recent Children's Oncology Group trials include: (1) Radiotherapy selection may be based on early chemotherapy response assessed by both FDG-PET and CT imaging, (2) A new prognostic factor score stratifies patients into risk categories; and (3) novel retrieval regimens were identified. A phase I/II trial is investigating Brentuximab vedotin (Bv) with gemcitabine in relapsed patients. A phase 3 trial will modify conventional chemotherapy and radiotherapy approaches through the addition of Bv, while incorporating translational biology to identify molecular targets.