Management of paediatric monomorphic post-transplant lymphoproliferative disorders with low-intensity treatment: A multicentre international experience.

BACKGROUND: Monomorphic post-transplant lymphoproliferative disorder (mPTLD) is a major cause of morbidity/mortality following solid organ transplant (SOT), with infection, mPTLD progression and organ rejection presenting equal risks. Balancing these risks is challenging, and the intensity of therapy required by individual patients is not defined. Although an increasing body of evidence supports the use of a stepwise escalation of therapy through reduction in immunosuppression (RIS) to rituximab monotherapy and low-dose chemo-immunotherapy, many centres still use B-cell non-Hodgkin lymphoma (B-NHL) protocols, especially when managing Burkitt/Burkitt-like (BL) PTLD. This study sought to define outcomes for children managed in the UK or Spanish centres using low-intensity first-line treatments. PROCEDURE: Retrospective data were anonymously collected on patients younger than 18 years of age, with post-SOT mPTLD diagnosed between 2000 and 2020. Only patients given low-intensity treatment at initial diagnosis were included. RESULTS: Fifty-six patients were identified. Age range was 0.9-18 years (median 10.7). Most (62.5%) had early-onset PTLD. Haematopathological analysis showed 75% were diffuse large B-cell like, 14.3% were BL and nine of 33 (27%) harboured a MYC-rearrangement. Stage III-IV disease was present in 78.6%. All but one had RIS, 26 received rituximab monotherapy and 24 low-dose chemo-immunotherapy, mostly R-COP. Intensified B-NHL chemotherapy was required in 10/56 (17.9%). There were a total of 13 deaths in this cohort, three related to PTLD progression. The 1-year overall survival (OS), event-free survival (EFS) and progression-free survival (PFS) were 92.8%, 78.6% and 80.2%, respectively. CONCLUSIONS: R-COP provides an effective low-dose chemotherapy option. Escalation to more intensive therapies in the minority of inadequately controlled patients is an effective strategy.

Multicenter study of pediatric Epstein-Barr virus-negative monomorphic post solid organ transplant lymphoproliferative disorders.

BACKGROUND: Pediatric Epstein-Barr virus-negative monomorphic post solid organ transplant lymphoproliferative disorder [EBV(-)M-PTLD] comprises approximately 10% of M-PTLD. No large multi-institutional pediatric-specific reports on treatment and outcome are available. METHODS: A multi-institutional retrospective review of solid organ recipients diagnosed with EBV(-)M-PTLD aged ≤21 years between 2001 and 2020 in 12 centers in the United States and United Kingdom was performed, including demographics, staging, treatment, and outcomes data. RESULTS: Thirty-six patients were identified with EBV(-)M-PTLD. Twenty-three (63.9%) were male. Median age (range) at transplantation, diagnosis of EBV(-)M-PTLD, and interval from transplant to PTLD were 2.2 years (0.1-17), 14 years (3.0-20), and 8.5 years (0.6-18.3), respectively. Kidney (n = 17 [47.2%]) and heart (n = 13 [36.1%]) were the most commonly transplanted organs. Most were Murphy stage III (n = 25 [69.4%]). Lactate dehydrogenase was elevated in 22/34 (64.7%) and ≥2 times upper limit of normal in 11/34 (32.4%). Pathological diagnoses included diffuse large B-cell lymphoma (n = 31 [86.1%]) and B-non-Hodgkin lymphoma (B-NHL) not otherwise specified (NOS) (n = 5 [13.9%]). Of nine different regimens used, the most common were: pediatric mature B-NHL-specific regimen (n = 13 [36.1%]) and low-dose cyclophosphamide, prednisone, and rituximab (n = 9 [25%]). Median follow-up from diagnosis was 3.0 years (0.3-11.0 years). Three-year event-free survival (EFS) and overall survival (OS) were 64.8% and 79.9%, respectively. Of the seven deaths, six were from progressive disease. CONCLUSIONS: EFS and OS were comparable to pediatric EBV(+) PTLD, but inferior to mature B-NHL in immunocompetent pediatric patients. The wide range of therapeutic regimens used directs our work toward developing an active multi-institutional registry to design prospective studies. PLAIN LANGUAGE SUMMARY: Pediatric Epstein-Barr virus-negative monomorphic post solid organ transplant lymphoproliferative disorders (EBV(-)M-PTLD) have comparable outcomes to EBV(+) PTLD, but are inferior to diffuse large B-cell lymphoma in immunocompetent pediatric patients. The variety of treatment regimens used highlights the need to develop a pediatric PTLD registry to prospectively evaluate outcomes. The impact of treatment regimen on relapse risk could not be assessed because of small numbers. In the intensive pediatric B-non-Hodgkin lymphoma chemoimmunotherapy group, 11 of 13 patients remain alive in complete remission after 0.6 to 11 years.

Genomic abnormalities of TP53 define distinct risk groups of paediatric B-cell non-Hodgkin lymphoma.

Children with B-cell non-Hodgkin lymphoma (B-NHL) have an excellent chance of survival, however, current clinical risk stratification places as many as half of patients in a high-risk group receiving very intensive chemo-immunotherapy. TP53 alterations are associated with adverse outcome in many malignancies; however, whilst common in paediatric B-NHL, their utility as a risk classifier is unknown. We evaluated the clinical significance of TP53 abnormalities (mutations, deletion and/or copy number neutral loss of heterozygosity) in a large UK paediatric B-NHL cohort and determined their impact on survival. TP53 abnormalities were present in 54.7% of cases and were independently associated with a significantly inferior survival compared to those without a TP53 abnormality (PFS 70.0% vs 100%, p < 0.001, OS 78.0% vs 100%, p = 0.002). Moreover, amongst patients clinically defined as high-risk (stage III with high LDH or stage IV), those without a TP53 abnormality have superior survival compared to those with TP53 abnormalities (PFS 100% vs 55.6%, p = 0.005, OS 100% vs 66.7%, p = 0.019). Biallelic TP53 abnormalities were either maintained from the presentation or acquired at progression in all paired diagnosis/progression Burkitt lymphoma cases. TP53 abnormalities thus define clinical risk groups within paediatric B-NHL and offer a novel molecular risk stratifier, allowing more personalised treatment protocols.

Risk of thyroid disorders in adult and childhood Hodgkin lymphoma survivors 40 years after treatment.

Thyroid abnormalities are well reported following childhood treatment for Hodgkin Lymphoma (HL). Limited information exists for adult patients and after modern treatments. We analyzed risks of thyroid disorders in 237 female participants treated at the Royal Marsden Hospital 1970-2015. Multivariable analyses of risk according to treatment and time-related factors, survival analyses, and Cox regression modeling were undertaken. Overall, 33.8% of patients reported thyroid disorders (hypothyroidism 30.0% and thyroid nodules 6.8%). Cumulative prevalence was 42.9% by 40 years follow-up. Risks were greatest after supradiaphragmatic radiotherapy (RR = 5.0, p < 0.001), and increasing dose (RR = 1.03/Gy, p < 0.001). There was no association with a chemotherapy agent. Risks of thyroid disease were as raised following adult as childhood treatment. There was no trend in risk by decade of supradiaphragmatic radiotherapy treatment. Risks of thyroid disease after supradiaphragmatic radiotherapy are as great after adult as childhood treatment and persist after more recent treatment periods.

Treatment and Outcome Analysis of 639 Relapsed Non-Hodgkin Lymphomas in Children and Adolescents and Resulting Treatment Recommendations.

Despite poor survival, controversies remain in the treatment for refractory or relapsed pediatric non-Hodgkin lymphoma (r/r NHL). The current project aimed to collect international experience on the re-induction treatment of r/r NHL, hematopoietic stem cell transplantation (HSCT), risk factors associated with outcome, and to suggest treatment recommendations. Inclusion criteria were (i) refractory disease, disease progression or relapse of any NHL subtype except anaplastic large cell lymphoma, (ii) age < 18 years at initial diagnosis, (iii) diagnosis in/after January 2000. Data from 639 eligible patients were evaluable. The eight-year probability of overall survival was 34 ± 2% with highly significant differences according to NHL subtypes: 28 ± 3% for 254 Burkitt lymphoma/leukemia, 50 ± 6% for 98 diffuse large B-cell lymphomas, 57 ± 8% for 41 primary mediastinal large B-cell lymphomas, 27 ± 3% for 177 T-lymphoblastic lymphomas, 52 ± 10% for 34 precursor-B-cell lymphoblastic lymphomas and 30 ± 9% for 35 patients with rare NHL subtypes. Subtype-specific factors associated with survival and treatment recommendations are suggested. There were no survivors without HSCT, except in few very small subgroups. Conclusions: There is an urgent need to further improve survival in r/r NHL. The current study provides the largest real-world series, which underlines the role of HSCT and suggests treatment recommendations.

Primary post-transplant lymphoproliferative disorder of the central nervous system: characteristics, management and outcome in 25 paediatric patients.

Primary central nervous system (CNS) post-transplant lymphoproliferative disorder (PTLD) in childhood is rare. Twenty-five patients were retrieved from nine European Intergroup for Childhood Non-Hodgkin's Lymphoma and/or international Berlin-Frankfurt-Münster Study Group members. Types of allografts included kidney (n = 11), liver (n = 4), heart (n = 5), bowel (n = 1) and haematopoietic stem cells (n = 4). Eighteen were male, 16 ≥ 10 years old, 21 had monomorphic disease and 24 solid intracranial tumour masses. Four-year event-free and overall survival rates were 50% ± 10% and 74% ± 9% respectively. This report represents the largest paediatric series of CNS PTLD reported to date, showing favourable survival odds following systemic and intrathecal chemotherapy and rituximab administration.

Infection Prevention and Control Measures at the Children Hospital Lahore: A My Child Matters Collaborative Project.

PURPOSE: Infection prevention among children with cancer is a major challenge at Children Hospital Lahore (CHL), a public health care facility in Pakistan with 1,000 new pediatric cancer admissions annually. The objective has been to reduce infections through collaboration between CHL and the St Jude Children's Hospital Global Infectious Disease program via a grant by the Sanofi Espoir foundation through the My Child Matters program. The aim of the current study was to describe the effect of the collaborative improvement strategy on existing infection prevention and control (IPC) standards at CHL. MATERIALS AND METHODS: Our work was a prospective before-and-after study to improve IPC standards. We compared the WHO Hand Hygiene Self-Assessment Framework and four modules of the St Jude modified Infection Control Assessment Tool (ICAT) scores over a 3-year period. Our strategy included creating a multidisciplinary team of pediatric oncologists, infectious disease physicians, nurses, a microbiologist, and a data manager; engaging in monthly online IPC mentoring sessions with St Jude Children's Hospital Global Infectious Disease program and My Child Matters mentors; performing daily inpatient health care-associated infection surveillance rounds; and performing regular hand hygiene training and compliance audits. RESULTS: Baseline needs assessment showed health care-associated infections identified by positive blood cultures as 8.7 infections per 1,000 patient-days. Deficient hand hygiene supplies, health education measures, and bed sharing of neutropenic patients were identified as major challenges. Our hand hygiene facility level, per WHO scores, increased from Inadequate to Intermediate/Consolidation by the end of the 3-year implementation (122 v 352 WHO Hand Hygiene Self-Assessment Framework scores). The sink:bed and hand sanitizer:bed ratios improved to 1:6 and 1:1, respectively. The ICAT general infection control module increased by 40% (45 v 78 ICAT scores) and hygiene compliance improved by 20%. CONCLUSION: Implementing a collaborative improvement strategy improved IPC standards in our center, which can be easily replicated in other pediatric oncology centers in lower- and middle-income countries.

Rare non-Hodgkin lymphoma of childhood and adolescence: A consensus diagnostic and therapeutic approach to pediatric-type follicular lymphoma, marginal zone lymphoma, and nonanaplastic peripheral T-cell lymphoma.

Pediatric-type follicular (PTFL), marginal zone (MZL), and peripheral T-cell lymphoma (PTCL) account each for <2% of childhood non-Hodgkin lymphoma. We present clinical and histopathological features of PTFL, MZL, and few subtypes of PTCL and provide treatment recommendations. For localized PTFL and MZL, watchful waiting after complete resection is the therapy of choice. For PTCL, therapy is subtype-dependent and ranges from a block-like anaplastic large cell lymphoma (ALCL)-derived and, alternatively, leukemia-derived therapy in PTCL not otherwise specified and subcutaneous panniculitis-like T-cell lymphoma to a block-like mature B-NHL-derived or, preferentially, ALCL-derived treatment followed by hematopoietic stem cell transplantation in first remission in hepatosplenic and angioimmunoblastic T-cell lymphoma.

High-dose etoposide and cyclophosphamide in adults and children with primary refractory and multiply relapsed acute leukaemias: The Royal Marsden experience.

INTRODUCTION: For patients with primary refractory and relapsed acute leukaemias allogeneic stem cell transplantation is the only hope for cure, but morphological remission is not always achieved after standard salvage regimens. Here we review the experience with high-dose etoposide and cyclophosphamide (HD-Et/Cy) in relapsed/refractory acute leukaemias at the Royal Marsden Hospital. PATIENTS AND METHODS: Twenty-three patients (15 adults, 8 children) with refractory/relapsed acute myeloblastic (n = 18; 78%), lymphoblastic (n = 4; 17%) or biphenotypic (n = 1; 4%) leukaemia who had failed to respond to at least one previous line of chemotherapy received HD-Et/Cy at our institution between 2006 and 2015. RESULTS: Overall response rate was 21.7% (95%CI 4.0-40.0). Median overall survival was 14.8 months (95%CI 9.1-49.1). Eight (35%) patients (7 AML, 1 biphenotypic leukaemia) proceeded to allogeneic transplant after one cycle of HD-Et/Cy: four of them (50%; 3 adults, 1 child) in complete remission and another four children (50%) with aplastic bone marrow with scattered blasts. Among the transplant recipients, three with AML (38%), ie. one adult (responder) and two children with aplastic bone marrow with scattered blasts, became long-term survivors 9.8, 4.4 and 2.5 years post-HD-Et/Cy, respectively. Toxicity profile was comparable to similar regimens with no treatment-related deaths. The most common grade 3-4 toxicity was febrile neutropenia (96%). CONCLUSIONS: HD-Et/Cy can salvage patients with refractory/relapsed AML who remain candidates for allogeneic stem cell transplantation after failure of standard salvage regimens and do not have access to clinical trials.

Preliminary experience on the use of PET/CT in the management of pediatric post-transplant lymphoproliferative disorder.

INTRODUCTION: Post-transplant lymphoproliferative disorder (PTLD) is a well-known complication following prolonged immunosuppression. Contrary to other lymphomas, there is no standardized imaging approach to assess PTLD either at staging or for response to therapy. Positron emission tomography/computed tomography (PET/CT) is an imaging modality that has proven to be useful in lymphoma. However, there is still limited data concerning its use in pediatric PTLD. Our study evaluates the use of PET/CT in pediatric PTLD at our institution. METHODS: To assess the role of PET/CT in pediatric PTLD, we reviewed the pediatric patients with PTLD who had undergone PET/CT at our institution between 2000 and 2016. RESULTS: Nine patients were identified. Six had PET/CT at diagnosis. All lesions seen on CT were identified with PET/CT. Fourteen PET/CTs were done during treatment. Eight PET/CTs were negative, including three where CT showed areas of uncertain significance. In these cases, PET/CT helped us to stop treatment and the patients remain in remission after a long follow-up (mean 74.3 months; range 12.4-180.9 months). PET/CT revealed additional disease in two cases, therefore treatment was intensified. Six biopsies and close follow-up was done to confirm PET/CT results. In one case, PET/CT did not identify central nervous system involvement demonstrated on magnetic resonance imaging. CONCLUSION: PET/CT may have an important role in the staging and follow-up of pediatric PTLD. In our cohort, PET/CT was helpful in staging and assessing treatment response and in clarifying equivocal findings on other imaging modalities.

Long-term risk of portal hypertension and related complications in children treated with 6-thioguanine for acute lymphoblastic leukemia: A single-center experience.

Long-term follow-up of 11 children with 6-thioguanine-induced hepatoportal toxicity is described. Features of persistent portal hypertension in eight patients after 9.7 ± 3.4 years (mean ± SD) of treatment were more common in late presenters. Splenomegaly, thrombocytopenia and altered hepatic echotexture were seen in six, eight and seven patients, respectively. One of the thrombocytopenic patients had heavy menstrual bleeding and pregnancy loss. Five of six patients who underwent upper gastrointestinal endoscopy had esophageal varices and four underwent banding. Late presentation in a subset of patients mandates long-term surveillance and follow-up for all patients treated with 6-thioguanine for early detection and management of hepatoportal complications.

Comparison of Presentation and Outcome in 100 Pediatric Hodgkin Lymphoma Patients Treated at Children Hospital, Lahore, Pakistan and Royal Marsden Hospital, UK.

OBJECTIVE: To compare differences in demographics and outcomes in childhood Hodgkin lymphoma (HL) presenting at the Children's Hospital Lahore (CHL), and Royal Marsden Hospital (RMH), UK. STUDY DESIGN: An observational comparative study. PLACE AND DURATION OF STUDY: From January 2011 to February 2012 at CH, Lahore and from October 2008 to February 2012 at RMH, UK. METHODOLOGY: Consecutive HL patients (50 from each hospital) were inducted. Data regarding age, gender, staging, histopathology and outcome were analysed. Clinical and pathological staging done according to Ann-Arbor and World Health Organization classification. Treatment duration was 6-8 months. They were followed for 6 months post-treatment. Frequencies of variables were noted and compared. Chi-square test was used for determining significance. RESULTS: Patients from Children's Hospital, Lahore were younger (mean 7.9 years) with male predominance (n=42, 84%). Histopathology showed Mixed Cellularity (MC) in 32 (64%), Nodular Sclerosis (NS) in 5 (10%), Lymphocyte Rich in 4 (8%) and lymphocyte depleted in 1 (2%), nodular lymphocyte predominant (NLP) in 1 (2%) each. Majority presented in stage IV (n=25,50%), or stage III (n=20,40%). Constitutional B symptoms were present in 37 (74%). Bone marrow involvement observed in 23 (46%). Remission was achieved in 42 (84%) patients; 2 (4%) relapsed, 4 (8%) expired and 2 (4%) left against medical advice. In contrast, RMH patients were older (mean 11.8 years.) and 30 (60%) were males. NS (n=40,80%) and NLP (n=6,12%) types were predominant. Two (4%) patients were in stage I, 27 (54%) in stage II, 12 (24%) in stage III and 9 (18%) presented in stage IV. Fourteen (28%) had B-symptoms. None had bone marrow disease. Event free survival was 46 (92%). Four (8%) patients relapsed. Three responded to second line therapy and one relapsed postautologous transplant. CONCLUSION: Significant differences were observed in age at presentation, stage, histopathology and extent of bone marrow involvement between the groups. Of interest is the bone marrow involvement in stage IV patients in Pakistan. Delayed diagnosis account for advanced stage but difference in pathological subtype needs further study.

Use of volumetric-modulated arc therapy for treatment of Hodgkin lymphoma.

To evaluate volumetric-modulated arc therapy (VMAT) for treatment of Hodgkin lymphoma (HL) in patients where conventional radiotherapy was not deliverable. A planning computed tomography (CT) scan was acquired for a twelve-year-old boy with Stage IIIB nodular sclerosing HL postchemotherapy with positive positron emission tomography scan. VMAT was used for Phase 1 (19.8Gy in 11 fractions) and Phase 2 (10.8Gy in 6 fractions) treatment plans. Single anticlockwise arc plans were constructed using SmartArc (Philips Radiation Oncology Systems, Fitchburg, WI) with control points spaced at 4°. The inverse-planning objectives were to uniformly irradiate the planning target volume (PTV) with the prescription dose while keeping the volume of lung receiving greater than 20Gy (V20Gy) to less than 30% and minimize the dose to the other adjacent organs at risk (OAR). Pretreatment verification was conducted and the treatment delivery was on an MLCi Synergy linear accelerator (Elekta Ltd, Crawley, UK). The planning results were retrospectively confirmed in a further 4 patients using a single PTV with a prescribed dose of 19.8Gy in 11 fractions. Acceptable dose coverage and homogeneity were achieved for both Phase 1 and 2 plans while keeping the lung V20Gy at 22.5% for the composite plan. The beam-on times for Phase 1 and Phase 2 plans were 109 and 200 seconds, respectively, and the total monitor units were 337.2MU and 292.5MU, respectively. The percentage of measured dose points within 3% and 3mm for Phase 1 and Phase 2 were 92% and 98%, respectively. Both plans were delivered successfully. The retrospective planning study showed that VMAT improved PTV dose uniformity and reduced the irradiated volume of heart and lung, although the volume of lung irradiated to low doses increased. Two-phased VMAT offers an attractive option for large volume sites, such as HL, giving a high level of target coverage and significant OAR sparing together with efficient delivery.

Outcome of childhood relapsed or refractory mature B-cell non-Hodgkin lymphoma and acute lymphoblastic leukemia.

Patients with childhood relapsed and refractory mature B-cell non-Hodgkin lymphoma (B-NHL) and acute lymphoblastic leukemia (B-ALL) are rare and have a dismal prognosis. The previous UK national analysis of 26 children over a 7-year period prior to 1996 had highlighted the poor outcome, with only three survivors. This 10-year multicenter study evaluated recent data, since 2000. Of 33 children, nine survived (27.3%), with a median follow-up of 4.3 years. On exclusion of six children treated with palliative intent, the survival was one-third (nine of 27; 33.3%). All patients with primary refractory disease (n = 7) and all except one with early relapse (n = 11) died. Administration of four doses of 375 mg/m(2) of rituximab was associated with a longer survival (p = 0.006). Response to reinduction (p < 0.001) and autologous hematopoietic stem cell transplant (auto-HSCT) (p = 0.003) were significant on multivariate analysis. Patients with a time to relapse of at least 6 months are potentially curable and must be offered intensive treatment with salvage chemotherapy, rituximab and auto-HSCT.