Pediatric lymphomas and histiocytic disorders of childhood

Presentation of B-cell lymphoma in childhood and adolescence: a systematic review and meta-analysis

BACKGROUND

The diagnosis of B-cell lymphoma, one of the commonest cancers seen in childhood and adolescence, is challenging. There is a crucial need to identify and delineate the prevalence of associated symptoms in order to improve early diagnosis.

AIMS

To identify clinical presentations associated with childhood and adolescent B-cell lymphomas and estimate symptom prevalence.

METHODS

A systematic review of observational studies and meta-analysis of proportions was carried out. Medline and EMBASE were systematically searched, with no language restrictions, from inception to 1st August 2022. Observational studies with at least 10 participants, exploring clinical presentations of any childhood and adolescent lymphoma, were selected. Proportions from each study were inputted to determine the weighted average (pooled) proportion, through random-effects meta-analysis.

RESULTS

Studies reported on symptoms, signs and presentation sites at diagnosis of 12,207 children and adolescents up to the age of 20. Hodgkin's lymphoma most frequently presented with adenopathy in the head-and-neck region (79% [95% CI 58%-91%]), whilst non-Hodgkin's lymphoma presented abdominally (55% [95% CI 43%-68%]). Symptoms associated with lymphoma included cervical lymphadenopathy (48% [95% CI 20%-77%]), peripheral lymphadenopathy (51% [95% CI 37%-66%]), B-symptoms (40% [95% CI 34%-44%]), fever (43% [95% CI 34%-54%]), abdominal mass (46% [95% CI 29%-64%]), weight loss (53% [95% CI 39%-66%]), head-and-neck mass (21% [95% CI 6%-47%]), organomegaly (29% [95% CI 23%-37%]), night sweats (19% [95% CI 10%-32%]), abdominal pain (28% [95% CI 15%-47%]), bone pain (17% [95% CI 10%-28%]) and abnormal neurology (11% [95% CI 3%-28%]).

CONCLUSION

This systematic review and meta-analysis of proportions provides insight into the heterogeneous clinical presentations of B-cell lymphoma in childhood and adolescence and provides estimates of symptom prevalence. This information is likely to increase public and clinical awareness of lymphoma presentations and aid earlier diagnosis. This review further highlights the lack of studies exploring childhood and adolescent lymphoma presentations in primary care, where patients are likely to present at the earliest stages of their disease.

Acute and Late Pulmonary Effects After Radiation Therapy in Childhood Cancer Survivors: A PENTEC Comprehensive Review

OBJECTIVES

The Pediatric Normal Tissue Effects in the Clinic (PENTEC) pulmonary task force reviewed dosimetric and clinical factors associated with radiation therapy (RT)-associated pulmonary toxicity in children.

METHODS

Comprehensive search of PubMed (1965-2020) was conducted to assess available evidence and predictive models of RT-induced lung injury in pediatric cancer patients (<21 years old). Lung dose for radiation pneumonitis (RP) was obtained from dose-volume histogram (DVH) data. RP grade was obtained from standard criteria. Clinical pulmonary outcomes were evaluated using pulmonary function tests (PFTs), clinical assessment, and questionnaires.

RESULTS

More than 2,400 abstracts were identified; 460 articles had detailed treatment and toxicity data; and 11 articles with both detailed DVH and toxicity data were formally reviewed. Pooled cohorts treated during 1999 to 2016 included 277 and 507 patients age 0.04 to 22.7 years who were evaluable for acute and late RP analysis, respectively. After partial lung RT, there were 0.4% acute and 2.8% late grade 2, 0.4% acute and 0.8% late grade 3, and no grade 4 to 5 RP. RP risk after partial thoracic RT with mean lung dose (MLD) <14 Gy and total lung V20Gy <30% is low. Clinical and self-reported pulmonary outcomes data included 8,628 patients treated during 1970 to 2013, age 0 to 21.9 years. At a median 2.9- to 21.9-year follow-up, patients were often asymptomatic; abnormal PFTs were common and severity correlated with lung dose. At ≥10-year follow-up, multi-institutional studies suggested associations between total or ipsilateral lung doses >10 Gy and pulmonary complications and deaths. After whole lung irradiation (WLI), pulmonary toxicity is higher; no dose response relationship was identified. Bleomycin and other chemotherapeutics at current dose regimens do not contribute substantially to adverse pulmonary outcomes after partial lung irradiation but increase risk with WLI.

CONCLUSIONS

After partial lung RT, acute pulmonary toxicity is uncommon; grade 2 to 3 RP incidences are <1%. Late toxicities, including subclinical/asymptomatic impaired pulmonary function, are more common (<4%). Incidence and severity appear to increase over time. Upon review of available literature, there appears to be low risk of pulmonary complications in children with MLD < 14 Gy and V20Gy <30% using standard fractionated RT to partial lung volumes. A lack of robust data limit guidance on lung dose/volume constraints, highlighting the need for additional work to define factors associated with RT-induced lung injury.

Barriers to long-term follow-up in pediatric Hodgkin lymphoma survivors

BACKGROUND/PURPOSE

Pediatric Hodgkin lymphoma (HL) survivors have an increased risk of late effects following treatment. Barriers at the patient, provider, and payor level adversely affect adherence to long-term follow-up.

METHODS

We conducted a retrospective chart review of HL survivors diagnosed from 1999 to 2014 at Texas Children's Hospital. HL survivors were considered lost to follow-up if there were no documented visits to Texas Children's Cancer Center Long-Term Survivor (LTS) clinic for 2 or more years after their last LTS clinic visit. Univariate and multivariable logistic regression analyses were conducted to explore factors contributing to loss to follow-up. Reasons for not attending subsequent LTS visits were assessed by phone interviews in a subset of lost to follow-up patients.

RESULTS

There were 120 HL survivors who had at least one LTS clinic visit in this timeframe; 64 (53%) were classified as lost to follow-up, and of these, 23 (36%) were interviewed. Eleven (47%) indicated that the reason for failure to follow-up was lack of or inadequate insurance, and seven (30%) stated they were unaware of the importance of continued follow-up. Loss to follow-up was associated with lack of insurance, earlier diagnosis, and lack of comorbidities in univariate analyses. Only earlier year of diagnosis (odds ratio [OR] 0.84, 95% confidence interval [CI]: 0.7-0.9, p = .01) and lack of insurance (OR 22.2, 95% CI: 4-123, p < .001) were associated with loss to follow-up in multivariable analyses.

CONCLUSIONS

Insurance status and awareness of the need for long-term follow-up care are key factors associated with loss to follow-up in survivors of HL. Targeted education and low-cost options for survivorship care are potential strategies for improving adherence to long-term follow-up care in HL survivors.

Role of non-chromosomal birth defects on the risk of developing childhood Hodgkin lymphoma: A Children's Oncology Group study

BACKGROUND

Non-chromosomal birth defects are an important risk factor for several childhood cancers. However, these associations are less clear for Hodgkin lymphoma (HL). Therefore, we sought to more fully elucidate the association between non-chromosomal birth defects and HL risk.

PROCEDURE

Information on cases (n = 517) diagnosed with HL (ages of 0-14) at Children's Oncology Group Institutions for the period of 1989-2003 was obtained. Control children without a history of cancer (n = 784) were identified using random digit dialing and individually matched to cases on sex, race/ethnicity, age, and geographic location. Parents completed comprehensive interviews and answered questions including whether their child had been born with a non-chromosomal birth defect. To test the association between birth defects and HL risk, conditional logistic regression was applied to generate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

Children born with any non-chromosomal birth defect were not more likely to be diagnosed with HL at 0-14 years of age (aOR: 0.91; 95% CI: 0.69-1.21). No associations were detected between major or minor birth defects and HL (aOR: 1.34; 95% CI: 0.67-2.67 and aOR: 0.88; 95% CI: 0.57-1.34, respectively). Similarly, no association was observed for children born with any birth defect and EBV-positive HL (aOR: 0.57; 95% CI: 0.25-1.26).

CONCLUSIONS

Previous assessments of HL in children with non-chromosomal birth defects have been limited. Using data from the largest case-control study of HL in those <15 years of age, we did not observe strong associations between being born with a birth defect and HL risk.

The changing landscape of pediatric histiocytoses: Birth, life, and transdifferentiation of pediatric histiocytes

Histiocytic neoplasms in the children are very rare, and histiocytoses can occur in the perinatal period. The presumed origins and presentation of specific histiocytoses in the pediatric age group are described. Common and newly described histiocytoses are presented including Langerhans cell histiocytosis, Rosai-Dorfman disease, histiocytic sarcoma, ALK positive histiocytosis, and hemophagocytic lymphohistiocytosis. Molecular findings common to pediatric histiocytoses are also discussed.

Childhood Malignancies-Clinico-demographic Profile of Patients Attending the Department of Otorhinolaryngology at a Tertiary Care Centre in North-East India

INTRODUCTION

Malignancies in children are different from those found in adults and are a significant cause of childhood mortality.They have varied clinical presentation depending on site and type of disease.It is essential to recognize the early signs and symptoms of malignancies in childhood, especially those involving head and neck region, so as to reduce childhood mortality and morbidity.

MATERIALS

A total of 2384 children were admitted over a period of 7 years. Out of these, 1004 fulfilled the inclusion criteria and were chosen for further evaluation.They were thoroughly evaluated by undertaking a detailed history and clinical examination.Whenever required, additional investigations were performed.After carrying out the necessary investigations, the cases were accordingly managed. Data was evaluated using proper statistical tools.

RESULTS

Out of 1004 cases fulfilling the inclusion criteria, 42 turned out to be malignant, with a male-to-female ratio of 1:1.2. Malignancies in children were more common in the age group of 11-18 years, followed by 1-5 years,6-10 years and 0-1 years,with rates of 59.5%, 21.4%, 16.7% and 2.4% respectively. A wide variety of tumour types were recorded,e.g.,Hodgkin's lymphoma,non-Hodgkin's lymphoma,acute leukemia,papillary carcinoma thyroid, nasopharyngeal carcinoma,Langerhans cell histiocytosis,rhabdomyosarcoma, olfactory neuroblastoma and salivary gland neoplasm.

CONCLUSION

Incidence of head and neck tumors in pediatric age group was found to be 1.76% with lymphoma being the most frequent.Commonest age of presentation was above 10 years. There was an overall female predominance with a male:female ratio of 1:1.2. Awareness of a potential malignancy and careful follow-up of children with suspicious head and neck cancers is mandatory for early diagnosis and prompt treatment.

Classical Hodgkin Lymphoma: From Past to Future-A Comprehensive Review of Pathophysiology and Therapeutic Advances

Hodgkin lymphoma, a hematological malignancy of lymphoid origin that typically arises from germinal-center B cells, has an excellent overall prognosis. However, the treatment of patients who relapse or develop resistant disease still poses a substantial clinical and research challenge, even though current risk-adapted and response-based treatment techniques produce overall survival rates of over 95%. The appearance of late malignancies after the successful cure of primary or relapsed disease continues to be a major concern, mostly because of high survival rates. Particularly in pediatric HL patients, the chance of developing secondary leukemia is manifold compared to that in the general pediatric population, and the prognosis for patients with secondary leukemia is much worse than that for patients with other hematological malignancies. Therefore, it is crucial to develop clinically useful biomarkers to stratify patients according to their risk of late malignancies and determine which require intense treatment regimens to maintain the ideal balance between maximizing survival rates and avoiding late consequences. In this article, we review HL's epidemiology, risk factors, staging, molecular and genetic biomarkers, and treatments for children and adults, as well as treatment-related adverse events and the late development of secondary malignancies in patients with the disease.

Imaging recommendations in pediatric lymphoma: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) are both malignancies originating in the lymphatic system and both affect children, but many features differ considerably, impacting workup and management. This paper provides consensus-based imaging recommendations for evaluation of patients with HL and NHL at diagnosis and response assessment for both interim and end of therapy (follow-up).

Differential newborn DNA methylation among individuals with complex congenital heart defects and childhood lymphoma

BACKGROUND

There is emerging evidence that children with complex congenital heart defects (CHDs) are at increased risk for childhood lymphoma, but the mechanisms underlying this association are unclear. Thus, we sought to evaluate the role of DNA methylation patterns on "CHD-lymphoma" associations.

METHODS

From >3 million live births (1988-2004) in California registry linkages, we obtained newborn dried bloodspots from eight children with CHD-lymphoma through the California BioBank. We performed case-control epigenome-wide association analyses (EWAS) using two comparison groups with reciprocal discovery and validation to identify differential methylation associated with CHD-lymphoma.

RESULTS

After correction for multiple testing at the discovery and validation stages, individuals with CHD-lymphoma had differential newborn methylation at six sites relative to two comparison groups. Our top finding was significant in both EWAS and indicates PPFIA1 cg25574765 was hypomethylated among individuals with CHD-lymphoma (mean beta = 0.04) relative to both unaffected individuals (mean beta = 0.93, p = 1.5 × 10^-12 ) and individuals with complex CHD (mean beta = 0.95, p = 3.8 × 10^-8 ). PPFIA1 encodes a ubiquitously expressed liprin protein in one of the most commonly amplified regions in many cancers (11q13). Further, cg25574765 is a proposed marker of pre-eclampsia, a maternal CHD risk factor that has not been fully evaluated for lymphoma risk in offspring, and the tumor microenvironment that may drive immune cell malignancies.

CONCLUSIONS

We identified associations between molecular changes present in the genome at birth and risk of childhood lymphoma among those with CHD. Our findings also highlight novel perinatal exposures that may underlie methylation changes in CHD predisposing to lymphoma.

The emerging role of pyroptosis in pediatric cancers: from mechanism to therapy

Pediatric cancers are the driving cause of death for children and adolescents. Due to safety requirements and considerations, treatment strategies and drugs for pediatric cancers have been so far scarcely studied. It is well known that tumor cells tend to progressively evade cell death pathways, which is known as apoptosis resistance, one of the hallmarks of cancer, dominating tumor drug resistance. Recently, treatments targeting nonapoptotic cell death have drawn great attention. Pyroptosis, a newly specialized form of cell death, acts as a critical physiological regulator in inflammatory reaction, cell development, tissue homeostasis and stress response. The action in different forms of pyroptosis is of great significance in the therapy of pediatric cancers. Pyroptosis could be induced and consequently modulate tumorigenesis, progression, and metastasis if treated with local or systemic therapies. However, excessive or uncontrolled cell death might lead to tissue damage, acute inflammation, or even cytokine release syndrome, which facilitates tumor progression or recurrence. Herein, we aimed to describe the molecular mechanisms of pyroptosis, to highlight and discuss the challenges and opportunities for activating pyroptosis pathways through various oncologic therapies in multiple pediatric neoplasms, including osteosarcoma, neuroblastoma, leukemia, lymphoma, and brain tumors.

Outcome and prognostic factors in childhood B non-Hodgkin lymphoma from India: Report by the Indian Pediatric Oncology Group (InPOG-NHL-16-01 study)

The literature on B-non-Hodgkin lymphoma (NHL) in India is restricted to individual hospital data. The study aimed to evaluate the epidemiology and outcome of B-NHL in our country. One hundred and ninety-one patients of B-NHL from 10 centers diagnosed between 2013 and 2016 were analyzed retrospectively. B/T lymphoblastic lymphoma and patients with inadequate data were excluded. The median age was 88 months (IQR: 56, 144) with an M:F ratio of 5.6:1. Undernourishment and stunting were seen in 36.5% and 22%. Primary site was abdomen in 66.5%. Hypoalbuminemia was noted in 82/170 (48.2%). Histological subtypes: Burkitt lymphoma (BL): 69.6%, Burkitt-like: 10.4%, and diffuse large B cell lymphoma (DLBCL): 13.6%, unclassified and others (6.4%). Stage distribution: I/II, 33 (17.3%), III, 114 (59.7%), and IV, 44 (23%). One-eighty-six patients took treatment. Protocols used were LMB and BFM in 160/186 (86%). At a median follow-up of 21.34 (IQR: 4.34, 36.57) months, the disease-free-survival (DFS) was 74.4% and event-free-survival (EFS) was 60.7%. Treatment-related mortality (TRM), relapse/progression and abandonment were 14.3%, 14.5%, and 8.4%, respectively. Bone marrow positivity, stage IV disease, and lactate dehydrogenase (LDH) > 2,000 U/l predicted inferior EFS. Stage IV disease, LDH > 2,000 U/l, bone marrow positivity, tumor lysis syndrome and low albumin predicted TRM; LDH retained significance on multivariate analysis for EFS and TRM [OR: 4.54, 95% CI: 1.14-20, p 0.03; OR 20, 95%CI: 1.69-250, p 0.017]. BL was the main histological subtype. High TRM and relapse/progression are hampering survival. An LDH > 2,000 U/l was adversely prognostic. These data demonstrate a need to develop a national protocol that balances toxicity and potential for cure.

Management of Aggressive Non-Hodgkin Lymphomas in the Pediatric, Adolescent, and Young Adult Population: An Adult vs. Pediatric Perspective

Simple Summary

This review details the diagnosis and treatment of primary non-Hodgkin lymphoma (NHL) in the pediatric and adolescent population. We also describe treatment modalities such as hematopoietic stem cell transplantation for relapsed or refractory NHL in patients that fail or do not respond to the initial therapy. We then detail the current advancements in treatment for patients that fail initial therapy such as CAR T-cell therapy, the use of immunotherapy that target surface makers on malignant cells and highlight areas where further research is needed. The purpose of our review is to inform the pediatric oncology community in regard to the various types of NHLs and emphasize areas where the science is evolving in the treatment of primary, relapsed or refractory disease.

Abstract

Non-Hodgkin lymphoma (NHL) is a broad entity which comprises a number of different types of lymphomatous malignancies. In the pediatric and adolescent population, the type and prognosis of NHL varies by age and gender. In comparison to adults, pediatric and adolescent patients generally have better outcomes following treatment for primary NHL. However, relapsed/refractory (R/R) disease is associated with poorer outcomes in many types of NHL such as diffuse large B cell lymphoma and Burkitt lymphoma. Newer therapies have been approved in the use of primary NHL in the pediatric and adolescent population such as Rituximab and other therapies such as chimeric antigen receptor T-cell (CAR T-cell) therapy are under investigation for the treatment of R/R NHL. In this review, we feature the characteristics, diagnosis, and treatments of the most common NHLs in the pediatric and adolescent population and also highlight the differences that exist between pediatric and adult disease. We then detail the areas of treatment advances such as immunotherapy with CAR T-cells, brentuximab vedotin, and blinatumomab as well as cell cycle inhibitors and describe areas where further research is needed. The aim of this review is to juxtapose established research regarding pediatric and adolescent NHL with recent advancements as well as highlight treatment gaps where more investigation is needed.

Immunotherapy Associated Neurotoxicity in Pediatric Oncology

Novel immunotherapies are increasingly being employed in pediatric oncology, both in the upfront and relapsed/refractory settings. Through various mechanisms of action, engagement and activation of the immune system can cause both generalized and disease site-specific inflammation, leading to immune-related adverse events (irAEs). One of the most worrisome irAEs is that of neurotoxicity. This can present as a large spectrum of neurological toxicities, including confusion, aphasia, neuropathies, seizures, and/or death, with variable onset and severity. Earlier identification and treatment, generally with corticosteroids, remains the mainstay of neurotoxicity management to optimize patient outcomes. The pathophysiology of neurotoxicity varies across the different therapeutic strategies and remains to be elucidated in most cases. Furthermore, little is known about long-term neurologic sequelae. This review will focus on neurotoxicity seen with the most common immunotherapies used in pediatric oncology, including CAR T cell therapy, alternative forms of adoptive cell therapy, antibody therapies, immune checkpoint inhibitors, and tumor vaccines. Herein we will discuss the incidence, pathophysiology, symptomatology, diagnosis, and management strategies currently being utilized for immunotherapy-associated neurotoxicity with a focus on pediatric specific considerations.

Hodgkin Lymphoma Presenting With Spinal Cord Compression: Challenges for Diagnosis and Initial Management

Hodgkin lymphoma (HL) can present with extra-nodal disease, but spinal cord compression is exceptionally rare. We describe a 15-year-old presenting with hip/back pain with normal initial examination. Persistent pain and raised inflammatory markers prompted further investigation with MRI, which revealed an epidural mass causing spinal cord compression. On examination, there was no palpable lymphadenopathy or cauda equina syndrome, but absent lower limb reflexes were noted. Following multidisciplinary discussion, it was determined that cauda equina syndrome was imminent and therefore surgical debulking was undertaken, both to prevent this complication and establish a diagnosis. At surgery, the tumor was highly vascular. Frozen section confirmed lesional material. Following surgery, and given the frozen section findings, a short course of steroids was commenced to reduce any peri-surgical edema. Unfortunately, histopathology was ultimately non-diagnostic, due to failure of immunohistochemistry on technically challenging material. Consequently, ultrasound-guided excision biopsy of a (non-palpable) cervical lymph node was performed five days later; histopathology showed typical effacement of the normal architecture and a conspicuous population of CD15/CD30-positive larger pale cells present, confirming nodular sclerosis classic HL, despite recent steroids. We review the available literature for HL presenting with spinal cord compression and describe the challenges for diagnosis and initial management in such cases.

Clinical Perspectives for 18F-FDG PET Imaging in Pediatric Oncology: Μetabolic Tumor Volume and Radiomics

Pediatric cancer, although rare, requires the most optimized treatment approach to obtain high survival rates and minimize serious long-term side effects in early adulthood. 18F-FDG PET/CT is most helpful and widely used in staging, recurrence detection, and response assessment in pediatric oncology. The well-known 18F-FDG PET metabolic indices of metabolic tumor volume (MTV) and tumor lesion glycolysis (TLG) have already revealed an independent significant prognostic value for survival in oncologic patients, although the corresponding cut-off values remain study-dependent and not validated for use in clinical practice. Advanced tumor “radiomic” analysis sheds new light into these indices. Numerous patterns of texture 18F-FDG uptake features can be extracted from segmented PET tumor images due to new powerful computational systems supporting complex “deep learning” algorithms. This high number of “quantitative” tumor imaging data, although not decrypted in their majority and once standardized for the different imaging systems and segmentation methods, could be used for the development of new “clinical” models for specific cancer types and, more interestingly, for specific age groups. In addition, data from novel techniques of tumor genome analysis could reveal new genes as biomarkers for prognosis and/or targeted therapies in childhood malignancies. Therefore, this ever-growing information of “radiogenomics”, in which the underlying tumor “genetic profile” could be expressed in the tumor-imaging signature of “radiomics”, possibly represents the next model for precision medicine in pediatric cancer management. This paper reviews 18F-FDG PET image segmentation methods as applied to pediatric sarcomas and lymphomas and summarizes reported findings on the values of metabolic and radiomic features in the assessment of these pediatric tumors.

A Summary of the Inaugural WHO Classification of Pediatric Tumors: Transitioning from the Optical into the Molecular Era

Pediatric tumors are uncommon, yet are the leading cause of cancer-related death in childhood. Tumor types, molecular characteristics, and pathogenesis are unique, often originating from a single genetic driver event. The specific diagnostic challenges of childhood tumors led to the development of the first World Health Organization (WHO) Classification of Pediatric Tumors. The classification is rooted in a multilayered approach, incorporating morphology, IHC, and molecular characteristics. The volume is organized according to organ sites and provides a single, state-of-the-art compendium of pediatric tumor types. A special emphasis was placed on "blastomas," which variably recapitulate the morphologic maturation of organs from which they originate. SIGNIFICANCE: In this review, we briefly summarize the main features and updates of each chapter of the inaugural WHO Classification of Pediatric Tumors, including its rapid transition from a mostly microscopic into a molecularly driven classification systematically taking recent discoveries in pediatric tumor genomics into account.

Non Hodgkin Lymphoma Among Children: Pathological Aspects and Diagnostic Challenges

Non-Hodgkin lymphoma (NHL) are common malignancies in children. Available data on clinico-pathological aspects of pediatric NHL in developping countries are limited and diagnostic approach appears more delicate with absence of molecular studies. The objectives of our study are: analyzing the pathological spectrum of NHL among children and highlighting challenges in the diagnosis including: limited biopsic material; unususal subtyptes, age group, or localization. We retrospectively analyzed clinico pathological characteristics of 101 NHL’s cases among children diagnosed in the Pediatric’s pathology unit over a period of 4 years There were 78 (77.2%) male and 23 (22.8%) female. The median age was 7.2 years. The most common histologic subtypes of NHL were Burkitt lymphoma in 65 patients (64.4% ); followed by lymphoblastic lymphoma in 22 patients, large B-cell lymphoma in 9 patients ( 8.9%); anaplastic T cell lymphoma in 3 patients; NOS mature T cell lymphoma and pediatric type follicular lympoma in 1 patient each. In conclusion, this study Morocco illustrates the pattern of distribution of NHL and emphasizes challenges in the diagnosis of these neoplasms.

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.

Five decades of low intensity and low survival: adapting intensified regimens to cure pediatric Burkitt lymphoma in Africa

Long-term cure of childhood Burkitt lymphoma (BL) in sub-Saharan Africa after treatment with single-agent cyclophosphamide has been documented for more than half of a century. Contemporary cure rates for the highest-risk patients with BL in high-income countries exceed 90% using intensive multiagent chemotherapy. By contrast, the majority of African children with BL still die. Data spanning 5 decades in Africa have repeatedly shown that the children most likely to achieve cure with limited cyclophosphamide regimens are those with lower-stage disease isolated to the jaw. Attempts to intensify the cyclophosphamide monotherapy backbone with the addition of vincristine, low-dose methotrexate, prednisone, doxorubicin, and/or low-dose cytarabine have not yielded significant improvement. High-dose methotrexate is a critical component in the treatment of childhood BL worldwide. Although initial efforts in Africa to incorporate high-dose methotrexate resulted in high treatment-related mortality, more recent collaborative experiences from North and West Africa, as well as Central America, demonstrate that it can be administered safely and effectively, despite limitations in supportive care resources. Recognizing the unacceptable disparity in curative outcomes for BL between the United States/Europe and equatorial Africa, there is a critical need to safely adapt contemporary treatment regimens to optimize curative outcomes amid the resource limitations in regions where BL is endemic. Here, we critically review reports of BL treatment outcomes from low- and middle-income countries, in addition to data from high-income countries that predated modern intensified regimens, to identify potential strategies to improve the therapeutic approach for children suffering from BL in sub-Saharan Africa.

Social gradient predicts survival disadvantage of African Americans/Black children with lymphoma

BACKGROUND

Cancer is the leading cause of disease-related mortality among children, 0-14 years, and lymphoma, a malignant neoplasm of the lymphoid cells, mostly lymphatic B and T cells is common among children. The current study aimed to assess the cumulative incidence (CmI), mortality, and survival in pediatric lymphoma.

MATERIALS AND METHODS

A retrospective cohort was utilized to examine children, 0-19 years with lymphoma for CmI, mortality and survival from the Surveillance, Epidemiology, and End Results (SEER) data. The variables assessed included social determinants of health, namely urbanity, median household income, and race. While chi square was used to characterize study variables by race, binomial regression was employed for mortality risk. The Cox proportional hazard model was used for survival modeling.

RESULTS

The CmI was higher among white children (76.67%) relative to Black/African American (AA, 13.44%), American Indian/Alaskan Native (AI/AN, 0.67%), as well as Asian/Pacific Islander (A/PI, 7.53%). With respect to mortality, there was excess mortality among Black/AA children compared to white children, Risk Ratio (RR) = 1.54, 95% CI, 1.33-1.79. Relative to whites, Blacks were 52% more likely to die, Hazard Ratio (HR) = 1.52, 95% CI, 1.30-1.78. Survival disadvantage persisted among Blacks/AA after controlling for the other confoundings, adjusted hazard ratio (aHR) = 1.54, 99% CI, 1.24-1.91.

CONCLUSION

In a large cohort of children with lymphoma, Black/AA children relative to whites presented with survival disadvantage, which was explained by urbanity and median household income, suggestive of transforming the physical and social environments in narrowing the racial differences in pediatric lymphoma survival in the US.

Pediatric Lymphoid and Histiocytic Lesions in the Head and Neck

Lymphoid and histiocytic lesions of the head and neck in pediatric patients is a fascinating topic as most of these lesions are benign, but that the neoplastic cases are essential to diagnose accurately for appropriate treatment. It is thought that 90% of children will have palpable lymph nodes between the ages of 4 to 8; most, but not all, are non-malignant and some resolve spontaneously without treatment. This paper will look at many of the benign and malignant lesions of both lymphocytic and histiocytic origin that present in the head and neck of children focusing on their diagnostic criteria. There is a very pertinent discussion of nonmalignant lymphoid proliferations, as infections and other reactive conditions dominate the pathology of pediatric lymphohistiocytic head and neck lesions. Discussion of those lymphomas which arise more frequently in the head and neck focuses on those seen in children and young adults such as classic Hodgkin lymphoma and Burkitt lymphoma, as well as new more controversial entities such as pediatric-type follicular lymphoma. Histiocytic lesions, both benign and malignant, are described and may be challenging to diagnose.

Case Report: Autoimmune Lymphoproliferative Syndrome vs. Chronic Active Epstein-Barr Virus Infection in Children: A Diagnostic Challenge

Autoimmune lymphoproliferative syndrome (ALPS) is a disorder characterized by a disruption of the lymphocyte apoptosis pathway, self-tolerance, and immune system homeostasis. Defects in genes within the first apoptosis signal (FAS)-mediated pathway cause an expansion of autoreactive double-negative T cells leading to non-malignant lymphoproliferation, autoimmune disorders, and an increased risk of lymphoma. The aim of the study was to show the diagnostic dilemmas and difficulties in the process of recognizing ALPS in the light of chronic active Epstein-Barr virus (CAEBV) infection. Clinical, immunological, flow cytometric, biomarkers, and molecular genetic approaches of a pediatric patient diagnosed with FAS-ALPS and CAEBV are presented. With the ever-expanding spectrum of molecular pathways associated with autoimmune lymphoproliferative disorders, multiple genetic defects of FAS-mediated apoptosis, primary immunodeficiencies with immune dysregulation, malignant and autoimmune disorders, and infections are included in the differential diagnosis. Further studies are needed to address the issue of the inflammatory and neoplastic role of CAEBV as a triggering and disease-modifying factor in ALPS.

Childhood cancer: Survival, treatment modalities, late effects and improvements over time

Since the 1960s, paediatric oncologists have gradually become better organised in large study groups and participation in clinical trials is today considered as the standard of care, with most children with cancer in Europe and North America being enrolled on available treatment protocols. Chemotherapy is nowadays the main element of therapy, but irradiation is still required for some patients. With the advent of multimodality therapy and supportive care, five-year cancer survival exceeds 80 % in most European and North American countries today. The substantial improvements in survival led to a constantly growing population of childhood cancer survivors. Concerns regarding the risk of late effects of the intensive cancer treatment at a young age, together with increasing numbers of survivors, have directed attention towards survivorship research. Survivors of childhood cancer are at longstanding risk of various severe somatic and mental health conditions attributable to the cancer and its treatment, as well as adverse social and socioeconomic consequences, and diminished psychological well-being and quality of life. It is, however, important to stress that some survivors have no or very mild adverse health conditions. Nevertheless, joint efforts are warranted for the care and long-term follow-up of childhood cancer patients. With this article, we provide a comprehensive overview of improvements in survival and treatment modalities over time, as well as the related somatic and mental late effects, and social and socioeconomic difficulties that these children might encounter later in life.

Educational Case: Burkitt Lymphoma

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.¹

CE: Hematologic Childhood Cancers: An Evidence-Based Review

Every year in the United States, thousands of children and adolescents are diagnosed with a hematologic cancer. That diagnosis and the prescribed course of treatment profoundly affect both the child and the family. This article provides a brief overview of the therapies used to treat such cancers, describes the presentations and diagnoses of the various hematologic cancers, and explains the treatments specific to each. Nursing care of the child and family is discussed, with an emphasis on education and supportive care.

Imaging for diagnosis, staging and response assessment of Hodgkin lymphoma and non-Hodgkin lymphoma

Hodgkin lymphoma and non-Hodgkin lymphoma are common malignancies in children and are now highly treatable. Imaging plays a major role in diagnosis, staging and response using conventional CT and MRI and metabolic imaging with positron emission tomography (PET)/CT and PET/MRI. Cross-sectional imaging has replaced staging laparotomy and splenectomy by demonstrating abdominal nodal groups and organ involvement. [F-18]2-fluoro-2-deoxyglucose (FDG) PET provides information on bone marrow involvement, and MRI elucidates details of cortical bone and confirmation of bone marrow involvement. The staging system for Hodgkin lymphoma is the Ann Arbor system with Cotswald modifications and is based on imaging, whereas the non-Hodgkin staging system is the St. Jude Classification by Murphy or the more recent revised International Pediatric Non-Hodgkin Lymphoma Staging System (IPNHLSS). Because all pediatric lymphomas are metabolically FDG-avid and identify all nodal, solid organ, cortical bone and bone marrow disease, staging evaluations require FDG PET as PET/CT or PET/MRI in both Hodgkin and non-Hodgkin lymphoma. Both diseases have in common issues of airway compromise at presentation demonstrated by imaging. Differences exist in that Hodgkin lymphoma has several independent poor prognostic factors seen by imaging such as large mediastinal adenopathy, Stage IV disease, systemic symptoms, pleural effusion and pericardial effusion. Non-Hodgkin lymphoma includes more organ involvement such as renal, ovary, central nervous system and skin. Early or interim PET-negative scans are a reliable indicator of improved clinical outcome and optimize risk-adapted therapy and patient management; imaging may not, however, predict who will relapse. A recent multicenter trial has concluded that it is usually sufficient for pediatric lymphoma at staging and interim assessment to evaluate children with PET imaging from skull base to mid-thigh. Various systems of assessment of presence of disease or response are used, including the Deauville visual scale, where avidity is compared to liver; Lugano, which includes size change as part of response; or quantitative PET, which uses standardized uptake values to define more accurate response. Newer methods of immunotherapy can produce challenges in FDG PET evaluation because of inflammatory changes that may not represent disease.

Exosomal MiRNAs in Pediatric Cancers

MicroRNAs (miRNAs) have generated great attention in oncology as they play a fundamental role in the regulation of gene expression and their aberrant expression is present in almost all types of tumors including pediatric ones. The discovery that miRNAs can be transported by exosomes, which are vesicles of 40–120 nm involved in cellular communication, that are produced by different cell types, and that are present in different biological fluids, has opened the possibility of using exosomal miRNAs as biomarkers. The possibility to diagnose and monitor the progression and response to drugs through molecules that can be easily isolated from biological fluids represents a particularly important aspect in the pediatric context where invasive techniques are often used. In recent years, the idea of liquid biopsy as well as studies on the possible role of exosomal miRNAs as biomarkers have developed greatly. In this review, we report an overview of all the evidences acquired in recent years on the identification of exosomal microRNAs with biomarker potential in pediatric cancers. We discuss the following herein: neuroblastoma, hepatoblastoma, sarcomas (osteosarcoma, Ewing’s sarcoma and rhabdoid tumors, and non-rhabdomyosarcoma soft tissue sarcoma), brain tumors, lymphomas, and leukemias.

Successful Use of EPOCH-R in 2 Young Adult Patients With Burkitt Lymphoma and Acute Kidney Injury: A Case Report

Pediatric Burkitt lymphoma has historically been treated with intensive methotrexate-based chemotherapy, which improves patient survival while causing severe toxicities. Young patients typically have better outcomes with intensive therapies, while adults and immunocompromised patients have higher toxicities and worse outcomes. Newer treatment regimens, including etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, rituximab (EPOCH-R), show promise for these patients. However, few studies exist to demonstrate efficacy and improved toxicity profile with EPOCH-R. We present 2 cases: a 25-year-old male with Down syndrome and an 18-year-old male with Burkitt lymphoma and significant renal injury who were successfully treated with EPOCH-R with minimal toxicities.

MiRNA Dysregulation in Childhood Hematological Cancer

For decades, cancer biology focused largely on the protein-encoding genes that have clear roles in tumor development or progression: cell-cycle control, apoptotic evasion, genome instability, drug resistance, or signaling pathways that stimulate growth, angiogenesis, or metastasis. MicroRNAs (miRNAs), however, represent one of the more abundant classes of cell modulators in multicellular organisms and largely contribute to regulating gene expression. Many of the ~2500 miRNAs discovered to date in humans regulate vital biological processes, and their aberrant expression results in pathological and malignant outcomes. In this review, we highlight what has been learned about the roles of miRNAs in some of the most common human pediatric leukemias and lymphomas, along with their value as diagnostic/prognostic factors.

Cutaneous Langerhans cell histiocytosis presenting with hypopigmented lesions: Report of two cases and review of literature

Langerhans cell histiocytosis is a rare group of disorders that results from the abnormal proliferation and accumulation of dendritic-derived cells in various organs of the body, such as the skin and bones. Hypopigmented macules are a rare cutaneous presentation of Langerhans cell histiocytosis that may pose a diagnostic dilemma when no other findings of Langerhans cell histiocytosis are present at the time of examination. We present 2 cases of the hypopigmented variant of Langerhans cell histiocytosis, including a case with histopathologic features of regression, and a review of the literature. These cases highlight the importance of including Langerhans cell histiocytosis in the differential diagnosis of an infant with hypopigmented macules and papules.

Primary gastric Burkitt lymphoma-induced anaemia: a case report and a literature review

Background.

Primary tumours of the gastrointestinal tract are very uncommon in children. They can present with anaemia caused by gastrointestinal acute or chronic bleeding. One of the most common gastrointestinal tumours is Burkitt lymphoma. This lymphoma is a highly aggressive, rapidly growing B-cell neoplasm, making survival without treatment possible only for a few weeks. For this reason it requires immediate hospitalization and treatment.

Case report.

We report a case of a gastric Burkitt lymphoma in an adolescent girl who presented with anaemia due to gastrointestinal bleeding. She received out-patient care with iron medications orally due to suspected iron-deficiency anaemia but there was no sufficient effect. The patient was referred to Children’s Oncohematology Department with a progression of symptoms (weakness, fatigue, sound in the ears, and nausea) five months after anaemia was diagnosed in the complete blood count. The imaging tests showed a massive solid tumour with bleeding in the stomach. The final diagnosis was a histologically atypical Burkitt lymphoma. Chemotherapy treatment was started according to NHL-BFM 2004 paediatric protocol.

Conclusions.

Non-Hodgin’s lymphoma is the most common malignancy of the gastrointestinal tract in children and about 75% of these tumours are Burkitt lymphomas. They can present with anaemia in the complete blood count due to bleeding. Reticulocyte test and serum ferritin level test help to differentiate pathophysiological origin of anaemia. Combination chemotherapy according to standardized protocols is the best current standard of care and has a very good clinical response without unfavourable risk factors.

Clinicopathological features and EBV infection status of lymphoma in children and adolescents in South China: a retrospective study of 662 cases

BACKGROUND

The clinicopathological features and Epstein-Barr virus (EBV) infection status of lymphoma in children and adolescents in South China is under-researched. South China is a well-known high-incidence area of EBV-associated nasopharyngeal carcinoma.

METHODS

A cohort of 662 consecutive children and adolescents' lymphomas was retrospectively analyzed and Epstein-Barr virus encoded RNAs (EBERs) in situ hybridization was performed to detect the EBV infection.

RESULTS

The majority (501/662, 75.7%) of lymphomas in children and adolescents was Non-Hodgkin lymphoma (NHL). One hundred sixty one cases (24.3%) were Hodgkin lymphoma (HL). Of the NHL, precursor cell lymphoma, mature B-cell lymphoma and peripheral T/NK-cell lymphoma accounted for 32.0%, 41.1% and 26.9% respectively. The five common subtypes were lymphoblastic lymphoma (32.0%), Burkitt lymphoma (BL) (21.0%), anaplastic large-cell lymphoma (ALCL) (14.2%), diffuse large B-cell lymphoma (DLBCL) (13.8%) and extranodal NK/T-cell lymphoma, nasal type (ENKTCL) (6.2%). EBV infection was detected in 58.9% classical Hodgkin lymphomas (CHLs), 21.4% mature B-cell lymphomas and 52.4% peripheral T/NK-cell lymphomas. Moreover, EBV was associated with high grade NHL including ENKTCL (100.0%), BL (30.5%) and DLBCL (17.6%).

CONCLUSION

The high proportion of peripheral T/NK-cell lymphomas in children and adolescents in South China are presented in this study and compared to western countries due to the high percentage of ENKTCL. ENKTCL is firmly associated with EBV infection, while more than half of HL, a portion of BL and DLBCL are related to EBV infection. This study conclusively demonstrates that EBV infection is more prevalent in children and adolescents with lymphomas in South China compared to western countries.

Clinical implications of oncogenic mutations in pulmonary Langerhans cell histiocytosis

PURPOSE OF REVIEW

Langerhans cell histiocytosis (LCH) is a neoplasm of dendritic cells with a wide clinical spectrum. Localized pulmonary LCH occurs in young adults with a history of smoking and can either resolve spontaneously or lead to progressive decline in pulmonary function. Young children can also present with localized disease - frequently bone or skin - or with multifocal or multisystem disease. Clinical outcomes in these patients also vary widely, ranging from spontaneous resolution to multiorgan failure and death. This review describes recent developments in our understanding of the underlying pathogenesis of LCH and how these discoveries and other research are affecting how the disease is classified, treated and monitored.

RECENT FINDINGS

Somatic mutations resulting in activation of the mitogen-activated protein kinase (MAPK) pathway were recently identified as a key pathogenetic mechanism in both pediatric and pulmonary LCH.

SUMMARY

Knowledge of underlying pathogenetic mechanisms of LCH transforming how this disease and other histocytic/dendritic disorders are classified, treated and monitored.

Pediatric Pulmonary Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma: A Case Report and Review of the Literature

Non-Hodgkin's lymphoma (NHL) is a common malignancy of childhood; however, a lung primary presentation is an uncommon finding, as is finding an association with the Epstein-Barr virus (EBV). We report the case of a 23-month-old female who developed EBV-associated diffuse large B-cell lymphoma (DLBCL) that was initially thought to be pneumonia. Extensive tissue necrosis, focal angioinvasion, and angiodestruction were observed. She was refractory to various therapy regimens, subsequently developed DLBCL in the central nervous system, and eventually expired. Although EBV+ DLBCL was initially considered to occur predominantly in elderly patients over 50 years of age, it is now increasingly recognized to occur in younger patients with primarily nodal involvement who have overall better prognoses. To our knowledge, this case is the first reported EBV+ DLBCL occurring in a patient below two years of age with lung involvement as the initial clinical presentation.

Signs and symptoms of rheumatic diseases as first manifestation of pediatric cancer: diagnosis and prognosis implications

OBJECTIVE

To assess the prevalence and describe the clinical, laboratory and radiological findings, treatment and outcome of children with cancer initially referred to a tertiary outpatient pediatric rheumatology clinic.

METHODS

Retrospective analysis of medical records from patients identified in a list of 250 new patients attending the tertiary Pediatric Rheumatology Clinic, Ribeirão Preto Medical School hospital, University of São Paulo, from July 2013 to July 2015, whose final diagnosis was cancer.

RESULTS

Of 250 patients seen during the study period, 5 (2%) had a cancer diagnosis. Among them, 80% had constitutional symptoms, especially weight loss and asthenia, and 60% had arthritis. Initially, all patients had at least one alteration in their blood count, lactate dehydrogenase was increased in 80% and a bone marrow smear was conclusive in 60% of patients. Bone and intestine biopsies were necessary for the diagnosis in 2 patients. JIA was the most common initial diagnosis. The definitive diagnosis was acute lymphoblastic leukemia (2 patients), M3 acute myeloid leukemia, lymphoma, and neuroblastoma (one case each). Of 5 patients studied, 3 (60%) are in remission and 2 (40%) died, one of them with prior use of steroids.

CONCLUSION

The constitutional and musculoskeletal symptoms common to rheumatic and neoplastic diseases can delay the diagnosis and consequently worsen the prognosis of neoplasms. Initial blood count and bone marrow smear may be normal in the initial framework of neoplasms. Thus, the clinical follow-up of these cases becomes imperative and the treatment, mainly with corticosteroids, should be delayed until diagnostic definition.

Nivolumab in the Treatment of Refractory Pediatric Hodgkin Lymphoma

The programmed death-1 (PD-1) pathway of immune evasion is exploited by many malignancies to limit host T-cell-mediated immune responses. Nivolumab is a PD-1-blocking monoclonal antibody that disrupts this pathway and is FDA approved for the treatment of metastatic melanoma, renal cell carcinoma, and squamous non-small cell lung cancer. In this case report, we describe the first published pediatric experience of nivolumab in refractory classic Hodgkin lymphoma. In this patient with primary refractory disease and high disease burden, cytokine release syndrome requiring inotropic support developed following the first infusion of nivolumab. The patient subsequently demonstrated a dramatic clinical response with resolution of fevers, transfusion independence, improvement in functional status, and very good partial response on PET/CT following a single dose. Nivolumab was continued with corticosteroid and antihistamine premedication without further adverse events and clinical benefit was sustained at 11 months after therapy initiation, despite evidence of slow radiographic disease progression.

Beyond Endemic Burkitt Lymphoma: Navigating Challenges of Differentiating Childhood Lymphoma Diagnoses Amid Limitations in Pathology Resources in Lilongwe, Malawi

Background. Although Burkitt lymphoma (BL) is the most common childhood lymphoma in sub-Saharan Africa, Hodgkin lymphoma (HL) and other non-Hodgkin lymphomas occur. Diagnosing non-jaw mass presentations is challenging with limited pathology resources. Procedure. We retrospectively analyzed 114 pediatric lymphomas in Lilongwe, Malawi, from December 2011 to June 2013 and compared clinical versus pathology-based diagnoses over two time periods. Access to pathology resources became more consistent in 2013 compared with 2011-2012; pathology interpretations were based on morphology only. Results. Median age was 8.4 years (2.1-16.3). The most common anatomical sites of presentation were palpable abdominal mass 51%, peripheral lymphadenopathy 35%, and jaw mass 34%. There were 51% jaw masses among clinical diagnoses versus 11% in the pathology-based group (P < .01), whereas 62% of pathology diagnoses involved peripheral lymphadenopathy versus 16% in the clinical group (P < .01). The breakdown of clinical diagnoses included BL 85%, lymphoblastic lymphoma (LBL) 9%, HL 4%, and diffuse large B-cell lymphoma (DLBCL) 1%, whereas pathology-based diagnoses included HL 38%, BL 36%, LBL 15%, and DLBCL 11% (P < .01). Lymphoma diagnosis was pathology confirmed in 19/66 patients (29%) in 2011-2012 and 28/48 (60%) in 2013 (P < .01). The percentage of non-BL diagnoses was consistent across time periods (35%); however, 14/23 (61%) non-BL diagnoses were pathology confirmed in 2011-2012 versus 16/17 (94%) in 2013. Conclusions. Lymphomas other than Burkitt accounted for 35% of childhood lymphoma diagnoses. Over-reliance on clinical diagnosis for BL was a limitation, but confidence in non-BL diagnoses improved with time as pathology confirmation became standard. Increased awareness of non-BL lymphomas in equatorial Africa is warranted.

Evaluation of maternal and perinatal characteristics on childhood lymphoma risk: A population-based case-control study

BACKGROUND

Lymphoma is one of the most common pediatric malignancies; however, there are few well-established risk factors. Therefore, we investigated if maternal and perinatal characteristics influenced the risk of childhood lymphoma.

PROCEDURE

Information on cases (n = 374) diagnosed with lymphoma and born in Texas for the period 1995-2011 was obtained from the Texas Cancer Registry. Birth certificate controls were randomly selected at a ratio of 10 controls per 1 case for the same period of 1995-2011. Unconditional logistic regression was used to generate unadjusted (OR) and adjusted odds ratios (aOR) and 95% confidence intervals (CI) for the following histologic subtypes: Hodgkin (HL), Burkitt (BL), and non-BL non-HLs (non-BL NHLs).

RESULTS

Overall, our findings indicate specific maternal and perinatal characteristics influence childhood lymphoma risk. Mexico-born mothers were more likely to have offspring who developed BL compared to mothers born in the United States (U.S.; aOR: 2.15; 95% CI: 1.06-4.36). Further, mothers who resided at time of delivery in a county on the U.S.-Mexico border were more likely to give birth to offspring who developed non-BL NHL (aOR: 1.72; 95% CI: 1.11-2.67) compared to mothers not living on the U.S.-Mexico border at time of infant birth. Last, infants born large-for-gestational-age experienced a twofold increase in BL risk (aOR: 2.00; 95% CI: 1.10-3.65).

CONCLUSIONS

In this population-based assessment, we confirmed previously reported risk predictors of childhood lymphoma, including sex of infant, while highlighting novel risk factors that warrant assessment in future studies.

Venous thrombosis in children and adolescents with Hodgkin lymphoma in Sweden

INTRODUCTION

Pediatric patients with Hodgkin lymphoma (HL) have several risk factors for venous thromboembolism (VTE). Although these patients are occasionally treated with thromboprophylaxis, no guidelines are implemented in Sweden. Scarce data from adult patients indicate an increased risk of VTE, but pediatric data is largely missing. Given the favorable overall survival of HL, there should reasonably be more focus on preventing complications.

MATERIALS AND METHODS

We conducted a retrospective cohort study, including all patients registered in the Childhood Cancer Registry under the age of 18years diagnosed with HL between January 2005 and December 2015 in Sweden.

RESULTS

Data was retrieved from the medical records of all 163 patients (100%) at six Swedish pediatric cancer centers. The incidence of VTE was 7.7% (symptomatic VTE 3.9%). The median follow-up was 3.4years (range 0.3-10.5). Only five patients (3.1%) were treated with thromboprophylaxis. All VTE events occurred in the older age category (11-17years) and all but one (92.7%) had a mediastinal mass. While the VTE did not significantly affect the treatment of HL, it caused increased morbidity and 2/12 developed a post-thrombotic syndrome. No significant risk factors for VTE were identified.

CONCLUSIONS

VTE is a relatively common complication of HL and its treatment, causing increased acute and long-term morbidity. However, due to limited number of events we could not demonstrate risk-factors for VTE that would identify patients who might benefit from thromboprophylaxis.