Survival trend and outcome prediction for pediatric Hodgkin and non-Hodgkin lymphomas based on machine learning.

Pediatric Hodgkin and non-Hodgkin lymphomas differ from adult cases in biology and management, yet there is a lack of survival analysis tailored to pediatric lymphoma. We analyzed lymphoma data from 1975 to 2018, comparing survival trends between 7,871 pediatric and 226,211 adult patients, identified key risk factors for pediatric lymphoma survival, developed a predictive nomogram, and utilized machine learning to predict long-term lymphoma-specific mortality risk. Between 1975 and 2018, we observed substantial increases in 1-year (19.3%), 5-year (41.9%), and 10-year (48.8%) overall survival rates in pediatric patients with lymphoma. Prognostic factors such as age, sex, race, Ann Arbor stage, lymphoma subtypes, and radiotherapy were incorporated into the nomogram. The nomogram exhibited excellent predictive performance with area under the curve (AUC) values of 0.766, 0.724, and 0.703 for one-year, five-year, and ten-year survival, respectively, in the training cohort, and AUC values of 0.776, 0.712, and 0.696 in the validation cohort. Importantly, the nomogram outperformed the Ann Arbor staging system in survival prediction. Machine learning models achieved AUC values of approximately 0.75, surpassing the conventional method (AUC = ~ 0.70) in predicting the risk of lymphoma-specific death. We also observed that pediatric lymphoma survivors had a substantially reduced risk of lymphoma after ten years b,ut faced an increasing risk of non-lymphoma diseases. The study highlights substantial improvements in pediatric lymphoma survival, offers reliable predictive tools, and underscores the importance of long-term monitoring for non-lymphoma health issues in pediatric patients.

18F-FDG PET/CT versus bone marrow biopsy in detecting bone marrow infiltration in initial staging of pediatric lymphoma.

BACKGROUND: To evaluate the efficacy of PET/CT using18F-FDG (18F-fluorodeoxyglucose) as a radiotracer compared to conventional bone marrow biopsy (BMB) in detecting infiltration to bone marrow (BM) in pediatric patients with lymphoma at the time of initial diagnosis. METHODS: 66 pediatric patients with lymphoma (47Hodgkin's and 19non-Hodgkin's lymphoma) were referred for initial staging by18F-FDG PET/CT study. All patients underwent bilateral iliac BMB and 18F-FDG PET/CT scan with no more than 2 weeks interval in-between. Follow-up for at least 6 months was used as a reference standard to compare diagnostic performance between two modalities in detecting bone marrow infiltration (BMI). RESULTS: Sensitivity, specificity, accuracy, as well as positive and negative predictive values of 18F-FDG PET/CT in detecting BMI were (80%, 86%, 85%, 63%, and 94%) in contrast to BMB (80%, 53%, 59%, 33%, and 90%) respectively. 18F-FDG PET/CT was concordant to BMB in 39/66 patients (59%). CONCLUSION: 18F-FDG PET/CT was more accurate and specific, with higher predictive values than BMB in detecting BMI during initial staging of pediatric lymphoma. In most pediatric lymphoma patients, 18F-FDG PET/CT can be used instead of BMB to determine BMI during their initial staging process.

Inborn errors of immunity and its clinical significance in children with lymphoma in China: a single-center study.

OBJECTIVE: To investigate the incidence, clinical and genetic characteristics of pediatric lymphoma patients of China with inborn errors of immunity (IEI)-related gene mutations, which have not been fully studied. METHOD: From Jan. 2020 to Mar. 2023, IEI-related genetic mutations were retrospectively explored in 108 children with lymphomas admitted to Beijing Children's Hospital by NGS. Genetic rule and clinical characteristics as well as treatment outcomes were compared between patients with or without IEI-related gene mutations. RESULTS: A total of 17 patients (15.7 %) harbored IEI-associated mutations, including 4 cases with X-linked lymphoproliferative syndrome (XLP), 3 cases had mutations in tumor necrosis factor receptor superfamily 13B (TNFRSF13B), 2 cases with Activated p110 syndrome (APDS). Patients with IEI all had alteration of immunocompetence with decreased levels of immunoglobulin and lymphocyte subsets. Recurrent infection existed in 41.2 % of patients. The 18-month event-free survival (EFS) and the overall response rate (ORR) of patients with IEI are significantly lower than those without IEI (33.86% vs. 73.26 %, p = 0.011; 52.94% vs. 87.91 %, p = 0.002, respectively). In addition, patients with IEI had a higher progression disease (PD) rate of 23.5 % than those without IEI of 4.4 % (p = 0.006). CONCLUSION: The present study demonstrated that IEI-associated lymphomas were much more common than originally appreciated in pediatric lymphomas, and those were insensitive to treatment and more likely to progress or relapse. The genomic analysis and a thorough review of the medical history of IEI can be used to distinguish them from pediatric lymphomas without IEI, which are beneficial for the early diagnosis and direct intervention.

Lifetime risks of second primary malignancies after pediatric Hodgkin lymphoma and non-Hodgkin lymphoma.

OBJECTIVES: Survivors after pediatric Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) are with lifetime risk for second primary malignancy (SPM). This necessitates a thorough analysis to better understand the potential long-term health implications for these individuals. METHODS: We used a US-wide population-based cancer registry data to quantify the SPM risk and identify its incidence patterns among pediatric lymphoma patients. RESULTS: We observed 4.74-fold (95% CI 4.27-5.25) and 3.40-fold (95% CI 2.78-4.10) increased risks of SPM in survivors after pediatric HL and NHL, respectively. Through over 40 years' follow-up, the cumulative incidence of SPM for pediatric lymphoma was persistently increasing, and here we firstly report the high 40-year cumulative incidence rates of SPM, 22.2% for HL and 12.6% for NHL, suggesting that SPM accounts for a great proportion of deaths among survivors. Of 6805 pediatric lymphomas, 462 (6.36%) developed a SPM, especially second breast and thyroid cancer, followed by hematologic neoplasms including leukemia and NHL. The competing risk analysis demonstrated gender, lymphoma subtype and radiotherapy were significantly associated with SPM. Different risk patterns of SPM were identified between pediatric HL and NHL. Chemotherapy accelerated SPM development but did not increase its incidence risk. CONCLUSION: Overall, patients after pediatric lymphoma can be with high lifetime risk of SPM, and more attention should be paid to SPM-related signs for early detection and intervention.

Large B-cell lymphoma with IRF4 rearrangement: a multi-centric study with focus on potential misleading phenotypes.

Large B-cell lymphoma with IRF4 rearrangement (LBCL-IRF4) is a rare lymphoid neoplasm, usually occurring in the pediatric/young-adult age. Despite this, subsets of cases occur in elderly patients and express CD5, possibly entering the differential diagnosis with adult aggressive lymphomas, such as blastoid/pleomorphic mantle cell lymphoma (MCL-B/P). To better characterize the clinical-pathological features and differential diagnosis of LBCL-IRF4, we conducted a multi-centric study on 12 cases, focusing on CD5, Cyclin D1, and SOX11 expression. While most cases had typical presentation, adult-to-elderly age at diagnosis and unusual anatomic locations were reported in 3/12 (25.0%) and 2/12 (16.7%) patients, respectively. Histologically, CD5 was positive in 4/12 (33.3%) cases, Cyclin D1 was invariably negative, and SOX11 was weakly/partially expressed in 1/12 (8.3%) case. In conclusion, LBCL-IRF4 can have unconventional clinical presentations that may challenge its recognition. Although CD5 is frequently expressed, negativity for Cyclin D1 and SOX11 contributes to the differential diagnosis with MCL-B/P.

Integration of RNA Sequencing, Whole Exome Sequencing, and Flow Cytometry Into Routine Diagnostic Workup of Pediatric Lymphomas.

The study was conducted to assess the feasibility of integrating state-of-the-art sequencing techniques and flow cytometry into diagnostic workup of pediatric lymphoma. RNA sequencing (RNAseq), whole exome sequencing, and flow cytometry were implemented into routine diagnostic workup of pediatric biopsies with lymphoma in the differential diagnosis. Within 1 year, biopsies from 110 children (122 specimens) were analyzed because of suspected malignant lymphoma. The experience with a standardized workflow combining histology and immunohistochemistry, flow cytometry, and next-generation sequencing technologies is reported. Flow cytometry was performed with fresh tissue in 83% (102/122) of specimens and allowed rapid diagnosis of T-cell and B-cell non-Hodgkin lymphomas. RNAseq was performed in all non-Hodgkin lymphoma biopsies and 42% (19/45) of Hodgkin lymphoma samples. RNAseq detected all but one of the translocations found by fluorescence in situ hybridization and PCR. RNAseq and whole exome sequencing identified additional genetic abnormalities not detected by conventional approaches. Finally, 3 cases are highlighted to exemplify how synergy between different diagnostic techniques and specialists can be achieved. This study demonstrates the feasibility and discusses the added value of integrating modern sequencing techniques and flow cytometry into a workflow for routine diagnostic workup of lymphoma. The inclusion of RNA and DNA sequencing not only supports diagnostics but also will lay the ground for the development of novel research-based treatment strategies for pediatric lymphoma patients.

Microorganismos aislados de hemocultivos en niños con leucemia y linforma: Seis años de seguimiento / Microorganisms isolated from blood cultures in children with leukemia and lymphoma: six years of follow-up

Las Leucemias y linfomas constituyen las enfermedades oncológicas más frecuentes en pediatría y las bacteriemias representan infecciones graves en estos pacientes. Objetivos: describir los microorganismos aislados de sangre en pacientes con leucemia aguda o linfoma pediátrico; comparar la incidencia de aislamientos según enfermedad de base; detallar las variaciones en la incidencia de dichos aislamientos y la evolución de su resistencia antimicrobiana. Estudio retrospectivo, observacional. Se incluyeron 823 episodios de bacteriemia en 467 pacientes pediátricos, entre julio-2016 y junio-2022, dividido en tres períodos (período-1: años 2016- 2018, período-2: años 2018-2020, período-3: años 2020-2022). Se aislaron 880 microorganismos: 55,3% gram negativos (GN), 40% gram positivos (GP) y 4,7% levaduras. En GN predominaron: enterobacterias (72%) y en GP: estreptococos del grupo viridans (SGV) (34,1%). Se encontró asociación entre LLA-enterobacterias (p=0,009) y LMA-SGV (p<0,001). Hubo aumento de GN entre los períodos 1 y 3 (p=0,02) y 2 y 3 (p=0,002) y disminución de GP entre 2 y 3 (p=0,01). Se registraron los siguientes mecanismos de resistencia: BLEE (16,4%), carbapenemasas: KPC (2,5%); MBL (2,7%) y OXA (0,2%); meticilinorresistencia en Staphylococcus aureus (20%) y estafilococos coagulasa negativos (95%), vancomicina resistencia en Enterococcus spp. (39%), SGV no sensibles a penicilina (44%) y a cefotaxima (13%). Hubo aumento de MBL entre los períodos 1 y 2 (p=0,02) y una tendencia en disminución de sensibilidad a penicilina en SGV entre el 1 y 3 (p=0,058). El conocimiento dinámico y análisis de estos datos es esencial para generar estadísticas a nivel local, fundamentales para el diseño de guías de tratamientos empíricos (AU)

Leukemias and lymphomas are the most common cancers in children and bacteremia is a severe infection in these patients. Objectives: to describe the microorganisms isolated from blood in pediatric patients with acute leukemia or lymphoma; to compare the incidence of isolates according to the underlying disease; and to detail the variations in the incidence of these isolates and the evolution of their antimicrobial resistance. Retrospective, observational study. We included 823 episodes of bacteremia in 467 pediatric patients seen between July-2016 and June-2022, divided into three periods (period-1: 2016- 2018, period-2: 2018-2020, period-3: 2020-2022). A total of 880 microorganisms were isolated: 55.3% were gram-negative (GN), 40% gram-positive (GP) and 4.7% yeasts. In GN there was a predominance of: enterobacteria (72%) and in GP viridans group streptococci (VGS) (34.1%). An association was found between ALL-enterobacteria (p=0.009) and AML-VGS (p<0.001). There was an increase in GN between periods 1 and 3 (p=0.02) and 2 and 3 (p=0.002) and a decrease in GP between 2 and 3 (p=0.01). The following resistance mechanisms were recorded: BLEE (16.4%), carbapenemases: KPC (2.5%), MBL (2.7%), and OXA (0.2%); methicillin resistance in Staphylococcus aureus (20%) and coagulase negative staphylococci (95%), vancomycin resistance in Enterococcus spp. (39%), VGS resistant to penicillin (44%) and to cefotaxime (13%). There was an increase in MBL between periods 1 and 2 (p=0.02) and a decreasing trend in penicillin sensitivity in VGS between periods 1 and 3 (p=0.058). Dynamic knowledge and analysis of these data is essential to generate statistics at the local level, which is fundamental for the design of empirical treatment guidelines (AU)

Modern Classification and Management of Pediatric B-cell Leukemia and Lymphoma.

Although pediatric hematopathology overlaps with that of adults, certain forms of leukemia and lymphoma, and many types of reactive conditions affecting the bone marrow and lymph nodes, are unique to children. As part of this series focused on lymphomas, this article (1) details the novel subtypes of lymphoblastic leukemia seen primarily in children and described since the 2017 World Health Organization classification and (2) discusses unique concepts in pediatric hematopathology, including nomenclature changes and evaluation of surgical margins in selected lymphomas.

Deep Learning-Based Segmentation and Volume Calculation of Pediatric Lymphoma on Contrast-Enhanced Computed Tomographies.

Lymphomas are the ninth most common malignant neoplasms as of 2020 and the most common blood malignancies in the developed world. There are multiple approaches to lymphoma staging and monitoring, but all of the currently available ones, generally based either on 2-dimensional measurements performed on CT scans or metabolic assessment on FDG PET/CT, have some disadvantages, including high inter- and intraobserver variability and lack of clear cut-off points. The aim of this paper was to present a novel approach to fully automated segmentation of thoracic lymphoma in pediatric patients. Manual segmentations of 30 CT scans from 30 different were prepared by the authors. nnU-Net, an open-source deep learning-based segmentation method, was used for the automatic segmentation. The highest Dice score achieved by the model was 0.81 (SD = 0.17) on the test set, which proves the potential feasibility of the method, albeit it must be underlined that studies on larger datasets and featuring external validation are required. The trained model, along with training and test data, is shared publicly to facilitate further research on the topic.

Pediatric-type follicular lymphoma: a short review.

Pediatric-type follicular lymphoma is an uncommon and newly recognized entity of lymphoid neoplasm commonly encountered in the young population. Despite its indolent clinical course and localized nodal involvement, it has been characterized by its high-grade histopathological features. The overlapping features between this disease and several entities have made approaching this unique entity significantly challenging, with all such features being reflected in the strict diagnostic criteria highlighted by the WHO 2016 lymphoid malignancy classification. Despite its characteristic high-grade histology, its cure rates have remained high, with relapse and transformation rarely occurring. Interestingly, several cases have achieved remission following nodal disease resection, possibly eliminating the need for chemotherapy and radiation and preventing long-term morbidities from later approaches in disease survivors.

Epstein-Barr virus and Burkitt's lymphoma. Associations in Iraqi Kurdistan and twenty-two countries assessed in the International Incidence of Childhood Cancer.

BACKGROUND: Burkitt's lymphoma (BL) has worldwide variations in incidence that are related to the age of Epstein-Barr virus (EBV) infection. This study examined the age-specific incidence rate (ASIR) of BL and community EBV seropositivity in Iraqi Kurdistan and compared results with data from countries tabulated in the International Incidence of Childhood Cancer volume 3 (IICC-3). METHODS: The ASIR (95% confidence intervals) of BL in Sulaimani Governorate of Iraqi Kurdistan were calculated for the years 2010-2020. Specimens from 515 outpatients were tested for IgG and IgM antibodies to EBV viral capsid antigen. RESULTS: In Sulaimani, 84% of BL occurred under 20 years of age, with an ASIR of 6.2 (4.7-7.7) per million children. This ASIR was not significantly different than that of Egypt, Morocco, Israel, Spain, or France. It was slightly higher than the ASIR of the United States, the United Kingdom, and Germany and markedly higher than for Asia and South Africa. In Africa and much of Asia, early childhood EBV exposure predominates, with nearly all children being infected by 5 years of age. In Sulaimani, just over 50% of children were EBV seropositive at 3 years old and 90% seropositivity was reached at 15 years of age. In Europe and North America, seropositivity is commonly delayed until adolescence or young adulthood and adult predominates over childhood BL. CONCLUSION: In the Middle East, childhood BL is relatively common and adult BL is rare. In Sulaimani, EBV seropositivity increases progressively throughout childhood and reaches 92% at mid-adolescence. This may reflect the Mid East more widely. We suggest that the high childhood and low adult BL rates may be a regional effect of a pattern of EBV exposure intermediate between early childhood and adolescent and young adult infections.

FDA approval summary: Crizotinib for pediatric and young adult patients with relapsed or refractory systemic anaplastic large cell lymphoma.

In January 2021, the U.S. Food and Drug Administration (FDA) approved crizotinib for pediatric patients 1 year and older and young adults with relapsed or refractory systemic anaplastic large cell lymphoma (sALCL). This is the first approval for pediatric sALCL. Approval was based on a single-arm trial of crizotinib monotherapy that included 26 patients, aged 1-20 years, with previously treated sALCL. Efficacy was based on centrally assessed objective response rate (88%) and duration of response. Herein, we highlight unique aspects of the regulatory review, including extension of the indication to young adults, postmarketing safety, and dose optimization strategies.

Primary epidural sporadic Burkitt lymphoma in a 3-year-old: Case report and literature review.

Background: Burkitt lymphoma (BL) is a common tumor of childhood that usually arises in the abdomen or pelvis in its sporadic form. In a minority of cases, BL can present with CNS involvement, usually as a secondary site. Rarely, BL can arise primarily in the epidural space and present with back pain, or less commonly, acute myelopathy. This presentation is a surgical emergency and requires vigilant management. Case Description: We describe a case of pediatric BL arising primarily within the epidural space and presenting with progressive difficulty walking in a 3-year-old boy. Progression to complete inability to walk, absent lower extremity deep tendon reflexes, and new urinary incontinence prompted MRI of the spine, which showed a lesion extending from T5 to T10 and wrapping around the anterior and posterior portions of the spine with evidence of spinal cord compression. The patient underwent decompressive laminectomies from T5 to T10 and partial debulking of the posterior portions of the tumor. Microscopic examination showed a prominent "starry sky" pattern with abundant mitotic figures. Immunohistochemistry confirmed the diagnosis of BL. The patient is 10 months post-op and continues to undergo chemotherapy with partial neurologic improvement. He was free of recurrence 10 months post-operative. Conclusion: This appears to be the youngest described patient presenting with acute myelopathy in primary paraspinal BL. Management should include surgical decompression of the spinal cord followed by one of the various described chemotherapeutic regimens. Preoperative staging and neurologic function correlate with prognosis.

Primary Cutaneous B-Cell Lymphomas in Children and Adolescents: A SEER Population-Based Study.

BACKGROUND: Although primary cutaneous B-cell lymphomas (PCBCL) comprise 25% of all cutaneous lymphomas, their incidence in the pediatric population is unknown, and the information on pediatric PCBCL has mostly been gathered from individual case reports or series from single centers. PATIENTS AND METHODS: This was a population-based, retrospective cohort study of patients in 18 cancer registries in the United States diagnosed between 2000 to 2016 through the Surveillance, Epidemiology, and End Results (SEER) program. Age-adjusted incidence rates were calculated for PCBCL in pediatric (<20 years) and adult (≥20 years) populations. Demographic, clinical, and pathological characteristics of PCBCL were compared between the two groups. RESULTS: A total of 48 pediatric and 5128 adult PCBCL cases were included. Median age at diagnosis was 16.5 years and 65 years in the two groups, respectively. The major histologic subtypes of pediatric cases were marginal zone lymphoma (77.1%), followed by diffuse large B-cell lymphoma (12.5%) and follicle center lymphoma (10.4%), which were equally distributed in adults. The age-adjusted pediatric PCBCL incidence rate (per 1,000,000 person-years) was 0.12 (95% CI 0.09-0.16). The incidence in the adult population was approximately 40-fold higher than the one observed in the pediatric group (IRR 41.4, 95% CI 31.2-56.2). All 48 pediatric cases were alive during a median follow-up time of 48 months. CONCLUSIONS: Pediatric PCBCL is a very rare disease affecting mostly adolescents of both sexes. The major histologic subtype is marginal zone lymphoma, and the prognosis is favorable.

Molecular features of non-anaplastic peripheral T-cell lymphoma in children and adolescents.

Non-anaplasticperipheral T-cell lymphomas (PTCL) are rare tumors in children, adolescents, and young adults (CAYA) with poor prognosis and scarce genetic data. We analyzed lymphoma tissue from 36 patients up to 18 years old with PTCL, not otherwise specified (PTCL-NOS), hepatosplenic T-cell lymphoma, Epstein-Barr virus (EBV)-positive T-lymphoproliferative diseases, subcutaneous panniculitis-like T-cell lymphoma, and other PTCL types. Twenty-three patients (64%) had at least one genetic variant detectable, including TET2, KMT2C, PIK3D, and DMNT3A. TP53 and RHOA variants, commonly found in adults, were not identified. Eight of 20 (40%) CAYA PTCL-NOS had no detectable mutations. The genetic findings suggest that CAYA PTCL differ from adult cases.

Trends in pediatric lymphoma incidence by global region, age and sex from 1988-2012.

BACKGROUND: Global variation in lymphoma incidence by type and age at diagnosis, region, sex, and Human Development Index (HDI) categories has not been reported, may shed light on potential biologic mechanisms and identify areas for targeted interventions. METHODS: Using the Cancer Incidence in Five Continents data from 1988 to 2012, we identified Hodgkin (HL), non-Hodgkin (NHL), and Burkitt lymphoma (BL) diagnosed in children aged 0-19 years. We estimated incidence rates (IRs; cases/million) and average annual percent change in incidence (AAPC; 95 % CI) by geographic region, sex, and HDI for each age group (0-9years and 10-19 years). RESULTS: There were 42,440 NHL, 38,683 H L, and 7703 included. Southern European (SE) 10-19-year-olds (yo) had the highest IR of NHL (19.6 cases/million) in 2008-2012. HL IRs for 0-9yo were <6 cases/million and >25 cases/million for 10-19yo in European regions and Oceania (OC). BL IRs were generally <5cases/million. Northern Europe (NE), SE, and OC 10-19yo had significantly increased APPCs in incidence for all lymphomas with the largest increases in BL (NE AAPC: 7.69 %; 95 % CI: 5.27, 10.16; SE AAPC: 5.21 %; 95 % CI: 3.26, 7.19; OC AAPC: 3.97 %; 95 % CI: 3.26, 4.70). BL incidence increased among males of all ages by approximately 2 %. NHL and BL incidence increased significantly among 10-19yo in very high HDI countries by approximately 3 %. CONCLUSIONS: Southern and Northern Europe and Oceania displayed increased incidence of all lymphomas studied from 1988 to 2012. BL incidence significantly increased in 8 of 15 global regions, males, and higher HDI countries over the study period. Mechanisms underlying these increases remain to be elucidated.

Value of baseline and end of chemotherapy 18F-FDG PET/CT in pediatric patients with Burkitt lymphoma.

The aim of this study was to analyze whether the baseline metabolic parameters of 18F-FDG PET/CT in pediatric patients with Burkitt lymphoma (BL) can predict treatment response and prognosis. We retrospectively analyzed 68 pediatric patients with BL who underwent PET/CT before treatment. PET images were analyzed semi-quantitatively by measuring the maximum standardized uptake (SUVmax), total metabolic tumor volume (tMTV), and total lesion glycolysis (TLG). Survival curves were plotted according to the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards regression models were used to assess the relation between potential variables and outcomes. tMTV and TLG were significantly lower in patients with complete response compared with those with partial response at the end of treatment. PET metabolic parameters (tMTV and TLG) were the independent prognostic values for outcome. TMTV and TLG were significantly connected with treatment response and prognosis in pediatric with BL.

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.

Iatrogenic Cushing's syndrome on 18F-FDG-PET/CT: A pitfall in metabolic assessment of oncologic response.

Iatrogenic Cushing's syndrome has very well-known stigmata on physical examination but can pose a diagnostic challenge when it rarely presents radiologically. We present a classic albeit rarely encountered imaging appearance of Iatrogenic Cushing's on 18F-FDG-PET/CT, with diffuse subcutaneous white adipose proliferation and metabolic activation in a 7-year old patient one-month after starting a high dose steroid regimen for lymphoma. There was an extreme shift in the expected FDG biodistribution with dominant localization to the subcutaneous adipose tissue. This metabolic shift led to sub-threshold visceral biodistribution, rendering the scan non-diagnostic with regards to assessment of oncologic response. Aside from detailing the characteristic imaging findings of Iatrogenic Cushing's and its clinical importance, we discuss the physiologic basis of this imaging pattern and the rarer differential diagnosis to consider when this pattern of uptake is encountered on 18F-FDG-PET/CT.