High ambient temperature in pregnancy and risk of childhood acute lymphoblastic leukaemia: an observational study.

BACKGROUND: High ambient temperature is increasingly common due to climate change and is associated with risk of adverse pregnancy outcomes. Acute lymphoblastic leukaemia is the most common malignancy in children, the incidence is increasing, and in the USA disproportionately affects Latino children. We aimed to investigate the potential association between high ambient temperature in pregnancy and risk of childhood acute lymphoblastic leukaemia. METHODS: We used data from California birth records (children born from Jan 1, 1982, to Dec 31, 2015) and California Cancer Registry (those diagnosed with childhood cancer in California from Jan 1, 1988, to Dec 31, 2015) to identify acute lymphoblastic leukaemia cases diagnosed in infants and children aged 14 years and younger and controls matched by sex, race, ethnicity, and date of last menstrual period. Ambient temperatures were estimated on a 1-km grid. The association between ambient temperature and acute lymphoblastic leukaemia was evaluated per gestational week, restricted to May-September, adjusting for confounders. Bayesian meta-regression was applied to identify critical exposure windows. For sensitivity analyses, we evaluated a 90-day pre-pregnancy period (assuming no direct effect before pregnancy), adjusted for relative humidity and particulate matter less than 2·5 microns in aerodynamic diameter, and constructed an alternatively matched dataset for exposure contrast by seasonality. FINDINGS: 6849 cases of childhood acute lymphoblastic leukaemia were identified and, of these, 6258 had sufficient data for study inclusion. We also included 307 579 matched controls. Most of the study population were male (174 693 [55·7%] of the 313 837 included in the study) and of Latino ethnicity (174 906 [55·7%]). The peak association between ambient temperature and risk of acute lymphoblastic leukaemia was observed in gestational week 8, where a 5°C increase was associated with an odds ratio of 1·07 (95% CI 1·04-1·11). A slightly larger effect was seen among Latino children (OR 1·09 [95% CI 1·04-1·14]) than non-Latino White children (OR 1·05 [1·00-1·11]). The sensitivity analyses supported the results of the main analysis. INTERPRETATION: Our findings suggest an association between high ambient temperature in early pregnancy and risk of childhood acute lymphoblastic leukaemia. Further replication and investigation of mechanistic pathways might inform mitigation strategies. FUNDING: Yale Center on Climate Change and Health, The National Center for Advancing Translational Science, National Institutes of Health.

Nutritional Status and Body Composition at Diagnosis, of South Indian Children with Acute Lymphoblastic Leukaemia (ALL).

BACKGROUND: Accurate estimation of body composition, particularly, Body Cell Mass (BCM), which is independent of hydration status is important in children with cancer. This study aimed to accurately measure the anthropometry and body composition of children with Acute Lymphoblastic Leukaemia (ALL) at diagnosis and compare them with healthy children from South India. METHODS: This was a cross-sectional study in children aged 2 to 8 y with ALL from St. John's Medical College Hospital, Bengaluru, and age and sex-matched, normal-weight children recruited as controls from communities. Anthropometry (weight, height, circumferences), skinfolds and body composition measurements using a whole-body potassium counter were performed. Body mass index-for-age, weight and height for age z-scores were calculated using WHO child growth standards. Biochemical markers, dietary intake and physical activity details were recorded. Categorical and continuous variables were analyzed by chi-square and independent t-tests respectively.     Results: The mean age of the children with ALL (n = 39) was 4.6±1.9 y and control group (n=39) was 4.7±1.9 y; 61.5% were boys. The prevalence of underweight, overweight/obesity and stunting were 17.9%, 7.7%, and 10.3% respectively. The mean weight and height, of children with ALL and children in the control group were 16.8±6.2 kg and 16.4±4.1 kg, 104.3±14.9 cm and 105.1±12.2 cm, respectively with no statistical difference. Children with ALL showed lower body cell mass index kg/m2 (4.6± 0.8), compared to children in the control group (4.7±0.9) p=0.527, but higher fat mass index kg/m2 (3.6±1.1 vs. 3.4±0.8) p=0.276. CONCLUSION: At diagnosis, anthropometric and body composition measurements were similar between children with ALL and children in the control group. The BCM showed a non-significant trend of being lower in children with ALL, which requires close monitoring during treatment. Evaluating early-stage nutritional status and body composition can help in planning appropriate interventions during treatment to prevent long term non-communicable diseases.

Coinfections and comorbidities observed in COVID-19 during the influenza season in the pediatric patient.

OBJECTIVE: To evaluate if the comorbidity and coinfections presented by SARS-CoV-2 infection vs. COVID-19 impact our Mexican children. METHOD: Prospective and observational study that included the 2020-2021 peak influenza season. All patients with a diagnosis of infection by SARS-CoV-2 vs. COVID-19 who were admitted to the Hospital Infantil de Mexico were analyzed. Real-time RT-PCR for SARS-CoV-2 was performed in all patients, determining E, RdRp and RP genes and protein N, as well as RT-PCR for detection of respiratory viruses. RESULTS: The inclusion criteria were met by 163 patients. The group with the highest risk of becoming ill was adolescents (40.4%), followed by schoolchildren and preschoolers (21.4% and 19.6% of the cases, respectively). There were three cases with viral coinfection: two (1.2%) with parvovirus B-19 and one (0.6%) with herpes type I; another two (1.2%) showed bacterial coinfection. The main comorbidity were obesity, acute lymphoblastic leukemia and arterial hypertension. Regarding mortality, we only had four cases (2.4%). CONCLUSIONS: Obesity, cancer, hypertension, heart disease and diabetes are comorbidity present in our patients, as referred to in literature, but not coinfections. In our study, we did not have any associated mortality related to comorbidity.

OBJETIVO: Evaluar el impacto de la comorbilidad y de las coinfecciones presentadas por la infección por SARS-CoV-2 vs. COVID-19 en niños mexicanos. MÉTODO: Estudio prospectivo y observacional que comprendió la temporada alta de influenza 2020-2021, analizando todos los pacientes con diagnóstico de infección vs. enfermedad por SARS-CoV-2 vs. COVID-19 que ingresaron al Hospital Infantil de México. Se realizó en todos RT-PCR en tiempo real para SARS-CoV-2, determinando gen E, gen RdRp, gen RP y proteína N, y RT-PCR multiplex para detección de virus respiratorios. RESULTADOS: Los criterios de inclusión los cumplieron 163 pacientes. El grupo con mayor riesgo de enfermar fueron los adolescentes (40.4%), seguidos de los escolares y preescolares (21.4% y 19.6% de los casos, respectivamente). Hubo tres casos con coinfección viral: dos (1.2%) con parvovirus B-19 y uno (0.6%) con herpes tipo I; hubo otros dos (1.2%) con coinfección bacteriana. La principal comorbilidad correspondió a obesidad, leucemia linfoblástica aguda e hipertensión arterial. En cuanto a mortalidad, solo hubo cuatro casos (2.4%). CONCLUSIONES: Obesidad, cáncer, hipertensión, cardiopatías y diabetes constituyen la comorbilidad en nuestros pacientes, como se refiere en la literatura, no así las coinfecciones. En nuestro estudio no hubo casos de mortalidad relacionada con la comorbilidad.

Epidemiology of acute lymphoblastic leukaemia in Sardinia, Italy: Age, sex, and environmental correlates.

Using a database of 1974-2003 incident cases of haematological malignancies, we explored the time trend, geographic spread and socio-economic and environmental correlates of ALL incidence in Sardinia, Italy, by sex and age. The age- and sex-standardized (World population) ALL incidence rate was 2.0 per 100,000 (95% CI 1.8 - 2.1) and showed variable trend patterns by sex and age. In the total population, ALL incidence showed an annual per cent change of -1.4% (95% CI -0.59 - -3.34) over the study period, with a knot separating a downward slope in 1974-1996 from an increase in 1996-2003. ALL incidence replicated such pattern in women but not men, whose incidence did not substantially vary over the study period (APC = -2.57%, 95% CI -5.45 - 0.26). Among women, the spatial analysis suggested a clustering of ALL in the southwestern part of the region, whilst only a commune had a high posterior probability of a high ALL incidence among men. Three unrelated communes showed a high posterior probability of ALL at age ≤ 24; only the most populated urban centre showed excess cases at age ≥ 25 years. There was no correlation between the geographic spread of ALL at ages ≤ 24 and ≥ 25 years (p = 0.082). Urban residence was a risk factor for the younger age group. Residences near industrial settlements and in the most populated urban centre were risk factors for subjects aged ≥ 25 years. Our findings suggest age-related differences in ALL aetiology.

Epidemiological characteristics and influencing factors of acute leukemia in children and adolescents and adults: a large population-based study.

OBJECTIVE: To assess the epidemiological characteristics and prognostic factors of acute leukemia (AL) in children and adolescents, and make comparisons between pediatric and adult patients. METHODS: This retrospective cohort study enrolled AL patients from the Surveillance, Epidemiology, and End Results (SEER) 1975-2016. OS in children and adolescents and adults with AL was compared and analyzed separately by age and AL subtype. RESULTS: Totally 61,694 AL patients were identified, with 45,411 (73.6%) adults and 16,283 (26.4%) children and adolescents. From 2000 to 2016, the incidence rates of AL [annual percent changes (APC) = 1.2, 95%CI = 0.9-1.6, P < 0.05] and acute lymphoblastic leukemia (ALL) (APC = 1.5, 95%CI = 1.1-1.8, P < 0.05) in children and adolescents were significantly increasing. For adults, AL (APC = 0.9, 95%CI = 0.3-1.5, P < 0.05), ALL (APC = 2.5, 95%CI = 2.0-3.1, P < 0.05) and acute myeloid leukemia (AML) (APC = 0.9, 95%CI = 0.4-1.5, P < 0.05) had significantly elevated incidence rates. Overall survival (OS) in children and adolescents with AL was significantly higher than that in adults with AL (log-rank P < 0.0001). OS in children and adolescents and adults with ALL, AML and AUL decreased with age (all log-rank P < 0.0001). Older age, male sex and black race were risk factors for the survival of children and adolescents and adults with ALL, AML and AUL. CONCLUSION: From 2000 to 2016, the incidence rates of AL in children and adolescents and adults were increasing. Children and adolescents with AL had significantly better OS than adults with AL, and OS declined with age in both children and adolescents and adults with ALL, AML and AUL.

Association between direct acting agents used for chronic hepatitis C virus infection and the occurrence of acute leukaemia - A disproportionality analysis.

BACKGROUND AND AIMS: A recent single-center study reported a significant increase in acute myeloid leukaemia (AML) cases, including mixed-phenotype acute leukaemia (MPAL), after exposure to direct acting agents (DAA). We investigated whether DAA use increased the risk of AML in patients with chronic hepatitis C virus (HCV) infection. METHODS: We conducted a disproportionality analysis of the WHO Pharmacovigilance database Vigibase up to 2020. Queries focused on all DAAs, subclasses, combinations or each DAA separately as well as interferon and ribavirin as negative controls. The primary outcome was AML. Secondary outcomes were AML without MPAL, MPAL, acute lymphoid leukemia (ALL) and acute leukemia (AL, high-level term encompassing AML, ALL, MPAL and unspecified acute leukemia [UAL]). The information component (IC0.25) and proportional reporting ratio (PRR0.25) were computed to assess a potential pharmacovigilance signal. RESULTS: We identified 49 notifications reporting any AL occurrence after anti-HCV treatments from June 1997 to December 2020: 23 (47%) involved a DAA, 24 (49%) interferon and 12 (24%) ribavirin. The DAAs sofosbuvir and ledipasvir were suspected in 74% (n = 17) and 39% (n = 9) of cases. The events reported were AML (n = 22), ALL (n = 11), AML and ALL (n = 1) and UAL (n = 15) and no MPAL. DAA, interferon or ribavirin were not significantly associated with AML, ALL or AL. CONCLUSION: This study did not find any association between DAA exposure and the occurrence of AML. Nevertheless, vigilance should remain, particularly for MPAL, which may not have been well captured in our study because of its rareness and high risk of misclassification.

Impact of the COVID-19 pandemic on utilization and cost for care of pediatric and young adult ALL.

OBJECTIVE: Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy and among the most common malignancies in young adults and requires a unique pattern of healthcare utilization including an acute/emergent presentation and an intensive initial 8 months of therapy followed by two years of outpatient treatment. The COVID-19 pandemic caused massive global disruptions in healthcare use and delivery. This report aims to examine the effects of the COVID-19 pandemic on the presentation, diagnosis and continued management of childhood and young adult ALL in regard to utilization and cost of care among commercially insured individuals in the United States. RESULTS: Utilizing a commercial insurance claims database, 529 pediatric and young adult patients were identified who were diagnosed with ALL between January 2016 and March 2021. New diagnoses were evaluated by era and demographics. Utilization was measured by COVID-related era as number of inpatient and outpatient encounters, inpatient days, and cumulative cost during the initial 8 months of therapy. None of these cost or utilization factors changed significantly during or shortly after the pandemic. These findings reinforce that the necessary care for pediatric and young adult ALL was unwavering despite the massive shifts in the healthcare system caused by the COVID-19 pandemic. This provides a valuable benchmark as we further examine the factors that influence the pandemic's impact on health equity and access to care, especially in vulnerable pediatric and young adult populations. This is the first investigation of the effect of the COVID-19 pandemic on utilization and cost of care in pediatric and young adult cancer.

Epidemiology and risk factors of bloodstream infections among adolescents and young adults with acute lymphoblastic leukaemia: An 11-year retrospective cohort study.

Adolescent and young adults (AYAs) belong to a unique category of patients diagnosed with acute lymphoblastic leukaemia (ALL). Bloodstream infection (BSI) is a leading cause of treatment-related mortality in ALL patients. However, the epidemiology and risk factors for mortality from BSIs in AYA patients remain unclear. In this study, we analysed these aspects in AYAs patients and compared similarities and differences with children (<15 years old) and older adults (>39 years old). We analysed the pathogenic epidemiology, antibiotic resistance and BSI risk factors of 73 children, 180 AYAs, and 110 older adults with ALL in three comprehensive hospitals from January 2010 to August 2021. The data on BSIs in AYAs were compared to that of the other two groups. In this study, the epidemiology of BSIs in AYAs was similar to that of older adult patients. Concerning clinical characteristics, most AYAs and older adults with BSIs were in a relapsed or uncontrolled state (34.5% vs. 35.4%, p = 0.861). In terms of pathogen distribution, Gram-negative bacteria (GNB) were the most common causative pathogens in AYAs and older adult groups. Extended-spectrum beta-lactamase (ESBL)-producing bacteria were more commonly found in AYAs than in children (32.8% vs. 16.4%, p = 0.09). Regarding risk factors, the length of hospitalization (>14 days) and renal inadequacy (creatinine ≥ 177 µmol/L) were influencing factors for 30-day mortality in AYAs patients with BSIs. In our study, AYA patients with BSIs showed clinical characteristics and pathogen distributions similar to those of older adult patients but quite different from those of children.

Exclusive Breastfeeding Duration and Risk of Childhood Cancers.

Importance: Breastfeeding has been suggested to protect against childhood cancers, particularly acute lymphoblastic leukemia (ALL). However, the evidence stems from case-control studies alone. Objective: To investigate whether longer duration of exclusive breastfeeding is associated with decreased risk of childhood ALL and other childhood cancers. Design, Setting, and Participants: This population-based cohort study used administrative data on exclusive breastfeeding duration from the Danish National Child Health Register. All children born in Denmark between January 2005 and December 2018 with available information on duration of exclusive breastfeeding were included. Children were followed up from age 1 year until childhood cancer diagnosis, loss to follow-up or emigration, death, age 15 years, or December 31, 2020. Data were analyzed from March to October 2023. Exposure: Duration of exclusive breastfeeding in infancy. Main Outcomes and Measures: Associations between duration of exclusive breastfeeding and risk of childhood cancer overall and by subtypes were estimated as adjusted hazard ratios (AHRs) with 95% CIs using stratified Cox proportional hazards regression models. Results: A total of 309 473 children were included (51.3% boys). During 1 679 635 person-years of follow-up, 332 children (0.1%) were diagnosed with cancer at ages 1 to 14 years (mean [SD] age at diagnosis, 4.24 [2.67] years; 194 boys [58.4%]). Of these, 124 (37.3%) were diagnosed with hematologic cancers (81 [65.3%] were ALL, 74 [91.4%] of which were B-cell precursor [BCP] ALL), 44 (13.3%) with central nervous system tumors, 80 (24.1%) with solid tumors, and 84 (25.3%) with other and unspecified malignant neoplasms. Compared with exclusive breastfeeding duration of less than 3 months, exclusive breastfeeding for 3 months or longer was associated with a decreased risk of hematologic cancers (AHR, 0.66; 95% CI, 0.46-0.95), which was largely attributable to decreased risk of BCP-ALL (AHR, 0.62; 95% CI, 0.39-0.99), but not with risk of central nervous system tumors (AHR, 0.96; 95% CI, 0.51-1.88) or solid tumors (AHR, 0.87; 95% CI, 0.55-1.41). Conclusions and Relevance: In this cohort study, longer duration of exclusive breastfeeding was associated with reduced risk of childhood BCP-ALL, corroborating results of previous case-control investigations in this field. To inform future preemptive interventions, continued research should focus on the potential biologic mechanisms underlying the observed association.

Feasibility and limitations of using commercial databases to evaluate residential mobility in registry-based research on childhood cancer.

BACKGROUND: Researchers have used commercial databases containing residential addresses to reduce exposure misclassification in case-control studies. Our objective is to evaluate the potential systematic bias regarding case status when reconstructing residential locations from commercial databases. METHODS: Our study population of 3640 Colorado-born children includes 520 children diagnosed with acute lymphocytic leukemia between 2002 and 2019. We aligned addresses and date ranges obtained from LexisNexis with registry dates to determine three dichotomous outcomes: Found in LexisNexis, conception date found in LexisNexis, and reference date/diagnosis date found in LexisNexis. We applied logistic regression to determine whether outcomes differed by case status. RESULTS: Mothers of cases were 39% more likely to be found in LexisNexis than mothers of controls (OR = 1.39, 95% CI: 0.97, 2). Of the mothers found in LexisNexis, a conception address was 33% more likely (OR= 1.33, 95% CI: 1.06, 1.66) and a reference/diagnosis address was 60% more likely (OR= 1.60, 95% CI: 1.21, 2.12) to be found for mothers of cases than mothers of controls. CONCLUSION: This study indicates that use of commercial databases to reconstruct residential locations may systematically bias results in case-control studies of childhood cancers.

"Characterization of residential proximity to sources of environmental carcinogens in clusters of Acute Lymphoblastic Leukemia in San Luis Potosi, Mexico".

BACKGROUND: Acute Lymphoblastic Leukemia (ALL) is the most prevalent neoplasia in children and teenagers in Mexico. Although epidemiological data supports that children's residence close to emissions from vehicular traffic or industrial processes increases the risk of ALL; and the IARC states that benzene, PAHs, and PM 2.5 are well-known environmental carcinogens, there is a gap in linking these carcinogenic hazards with the sources and their distribution from scenario perspective. AIM: To identify ALL clusters in the population under 19 years of age and characterize the environment at the neighborhood level by integrating information on sources of carcinogenic exposure using spatial analysis techniques in the Metropolitan Area of San Luis Potosi, Mexico. METHODS: Using the Kernel Density test, we designed an ecological study to identify ALL clusters from incident cases in the population under 19 years of age. A multicriteria analysis was conducted to characterize the risk at the community level from carcinogenic sources. A hierarchical cluster analysis was performed to characterize risk at the individual level based on carcinogenic source count within 1 km for each ALL case. RESULTS: Eight clusters of carcinogenic sources were located within the five identified ALL clusters. The multicriteria analysis showed high-risk areas (by density of carcinogenic source) within ALL clusters. CONCLUSIONS: This study has a limited source and amount of available data on ALL cases, so selection bias is present as well as the inability to rule out residual confounding factors, since covariates were not included. However, in this study, children living in environments with high vehicular density, gas stations, brick kilns, incinerators, commercial establishments burning biomass, or near industrial zones may be at higher risk for ALL.

COVID-19 in Pediatric Patients With Acute Lymphoblastic Leukemia or Lymphoma.

Importance: COVID-19 in pediatric patients with acute lymphoblastic leukemia or lymphoma (ALL/LLy) has not been described in detail and may affect chemotherapy administration and long-term outcomes. Objective: To describe the clinical presentation of COVID-19 and chemotherapy modifications in pediatric patients with ALL/LLy. Design, Setting, and Participants: This is a retrospective case series of patients at St Jude Children's Research Hospital and its affiliate sites with newly diagnosed ALL/LLy who were treated on the Total XVII protocol (NCT03117751) between March 30, 2020, and June 20, 2022. Participants included patients aged 1 to 18 years who were receiving protocol chemotherapy. Acute symptoms and chemotherapy modifications were evaluated for 60 days after the COVID-19 diagnosis, and viral clearance, adverse events, and second SARS-CoV-2 infections were followed up during the 27-month study period. Exposures: SARS-CoV-2; all patients were screened at least weekly and at symptom onset and/or after known exposure to SARS-CoV-2. Main Outcomes and Measures: Description of the spectrum of COVID-19 illness and chemotherapy modifications. Results: Of 308 pediatric patients, 110 (36%) developed COVID-19 at a median age of 8.2 (IQR, 5.3-14.5) years. Sixty-eight patients (62%) were male. Most patients were in the continuation/maintenance phase of chemotherapy (101 [92%]). Severe disease was rare (7 [6%]) but was associated with older age, higher white blood cell counts at ALL/LLy diagnosis, lower absolute lymphocyte counts at COVID-19 diagnosis, abnormal chest imaging findings, and SARS-CoV-2 reinfection. Rare but serious thrombotic events included pulmonary embolism and cerebral venous sinus thrombosis (n = 1 for each). No multisystem inflammatory syndrome in children or death was seen. SARS-CoV-2 reinfection occurred in 11 patients (10%) and was associated with older age and with receiving standard or high-risk vs low-risk ALL/LLy therapy. Chemotherapy interruptions occurred in 96 patients (87%) and were longer for patients with severe disease, SARS-CoV-2 reinfection, and/or a COVID-19 diagnosis during the pre-Omicron variant period vs the post-Omicron period (after December 27, 2021). Conclusions and Relevance: In this case series of COVID-19 in pediatric patients with ALL/LLy, severe COVID-19 was rare, but chemotherapy administration was affected in most patients. Long-term studies are needed to establish the outcomes of COVID-19 in this population.

Solar ultraviolet radiation exposure, and incidence of childhood acute lymphocytic leukaemia and non-Hodgkin lymphoma in a US population-based dataset.

BACKGROUND: Acute lymphocytic leukaemia (ALL) and non-Hodgkin lymphoma (NHL) are among the commonest types of childhood cancer. Some previous studies suggested that elevated ultraviolet radiation (UVR) exposures increase ALL risk; many more indicate NHL risk is reduced. METHODS: We assessed age<20 ALL/NHL incidence in Surveillance, Epidemiology and End Results data using AVGLO-derived UVR irradiance/cumulative radiant exposure measures, using quasi-likelihood models accounting for underdispersion, adjusted for age, sex, racial/ethnic group and other county-level socioeconomic variables. RESULTS: There were 30,349 cases of ALL and 8062 of NHL, with significant increasing trends of ALL with UVR irradiance (relative risk (RR) = 1.200/mW/cm2 (95% CI 1.060, 1.359, p = 0.0040)), but significant decreasing trends for NHL (RR = 0.646/mW/cm2 (95% CI 0.512, 0.816, p = 0.0002)). There was a borderline-significant increasing trend of ALL with UVR cumulative radiant exposure (RR = 1.444/MJ/cm2 (95% CI 0.949, 2.197, p = 0.0865)), and significant decreasing trends for NHL (RR = 0.284/MJ/cm2 (95% CI 0.166, 0.485, p < 0.0001)). ALL and NHL trend RR is substantially increased among those aged 0-3. All-age trend RRs are most extreme (increasing for ALL, decreasing for NHL) for Hispanics for both UVR measures. CONCLUSIONS: Our more novel finding, of excess UVR-related ALL risk, is consistent with some previous studies, but is not clear-cut, and in need of replication.

The burden of acute lymphoid leukemia among adolescents and young adults in the Western Pacific Region: evidence from Global Burden Disease 2019.

PURPOSE: Acute lymphoblastic leukemia (ALL) is a type of blood cancer that affects white blood cells. Here, we use data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, to estimate the burden and incidence rate changes in adolescents and young adults (AYA) ALL in the Western Pacific Region and to reveal potential risk factors of incidence- and mortality rates. METHODS: The GBD 2019 study data was stratified by sex, age, country, and territory. We calculated the Estimated annual percentage changes (estimated APC) in mortality and incidence rates for each of the 25 countries and territories of the western Pacific region from 1990 to 2019. RESULTS: This study found global AYA ALL incidence rates had increased while the mortality rates had decreased between 1990 and 2019. Moreover, healthcare access and quality (HAQ), and government per capita health spending were identified as country-level risk factors of AYA ALL incidence rates, while HAQ, male education, and sex were identified as mortality rate predictors in 25 Western Pacific Region countries. CONCLUSION: To address and reduce the burden of incidence and mortality among AYA, various regions around the world, particularly developing countries, could revise their AYA prevention and treatment strategies.

Residential exposure to magnetic fields from transformer stations and risk of childhood leukemia.

BACKGROUND: Several studies have documented an increased risk of leukemia among children exposed to magnetic fields from high-voltage power lines, with some evidence of dose-response relation. However, findings in some studies have been inconsistent, and data on the effects of different sources of exposure are lacking. In this study, we evaluated the relation of childhood leukemia risk to exposure to magnetic fields from transformer stations. METHODS: We conducted a population-based case-control study in a pediatric population of two Northern Italian provinces of Modena and Reggio Emilia. We included 182 registry-identified childhood leukemia cases diagnosed during 1998-2019 and 726 population controls matched on sex, year of birth, and province of residence. We assessed exposure by calculating distance from childhood residence to the nearest transformer station within a geographical information system, computing disease odds ratios (ORs) and 95% confidence intervals (CIs) using conditional logistic regression, adjusting for potential confounders. We evaluated exposure using two buffers (15 m and 25 m radius) and assessed two case groups: leukemia (all subtypes) and acute lymphoblastic leukemia (ALL). RESULTS: Residing within 15 m of a transformer station (vs. ≥15 m) was not appreciably associated with risk of leukemia (all subtypes) or ALL. We found similar results using a less stringent exposure buffer (25 m). Among children aged ≥5 years, the adjusted ORs were 1.3 (95% CI 0.1-12.8) for leukemia and 1.3 (95% CI 0.1-12.4) for ALL using the 15 m buffer, while they were 1.7 (95% CI 0.4-7.0) for leukemia and 0.6 (95% CI 0.1-4.8) for ALL using the 25 m buffer. CONCLUSIONS: While we found no overall association between residential proximity to transformer stations and childhood leukemia, there was some evidence for elevated risk of childhood leukemia among children aged ≥5 years. Precision was limited by the low numbers of exposed children.

Obesity and Leukemia: Biological Mechanisms, Perspectives, and Challenges.

PURPOSE OF REVIEW: To examine the epidemiological data on obesity and leukemia; evaluate the effect of obesity on leukemia outcomes in childhood acute lymphoblastic leukemia (ALL) survivors; assess the potential mechanisms through which obesity may increase the risk of leukemia; and provide the effects of obesity management on leukemia. Preventive (diet, physical exercise, obesity pharmacotherapy, bariatric surgery) measures, repurposing drugs, candidate therapeutic agents targeting oncogenic pathways of obesity and insulin resistance in leukemia as well as challenges of the COVID-19 pandemic are also discussed. RECENT FINDINGS: Obesity has been implicated in the development of 13 cancers, such as breast, endometrial, colon, renal, esophageal cancers, and multiple myeloma. Leukemia is estimated to account for approximately 2.5% and 3.1% of all new cancer incidence and mortality, respectively, while it represents the most frequent cancer in children younger than 5 years. Current evidence indicates that obesity may have an impact on the risk of leukemia. Increased birthweight may be associated with the development of childhood leukemia. Obesity is also associated with worse outcomes and increased mortality in leukemic patients. However, there are several limitations and challenges in meta-analyses and epidemiological studies. In addition, weight gain may occur in a substantial number of childhood ALL survivors while the majority of studies have documented an increased risk of relapse and mortality among patients with childhood ALL and obesity. The main pathophysiological pathways linking obesity to leukemia include bone marrow adipose tissue; hormones such as insulin and the insulin-like growth factor system as well as sex hormones; pro-inflammatory cytokines, such as IL-6 and TNF-α; adipocytokines, such as adiponectin, leptin, resistin, and visfatin; dyslipidemia and lipid signaling; chronic low-grade inflammation and oxidative stress; and other emerging mechanisms. Obesity represents a risk factor for leukemia, being among the only known risk factors that could be prevented or modified through weight loss, healthy diet, and physical exercise. Pharmacological interventions, repurposing drugs used for cardiometabolic comorbidities, and bariatric surgery may be recommended for leukemia and obesity-related cancer prevention.

Increased Incidence of TdT-negative Pre-B Acute Lymphoblastic Leukemia Associated With Poor Prognostic Features Among Mexican Children in Central Mexico.

Mexican and Hispanic children in Mexico and the United States, respectively, have the highest incidence and worst outcomes of pre-B acute lymphoblastic leukemia (ALL) compared with other racial/ethnic groups. Terminal deoxynucleotidyl transferase (TdT) is an intranuclear DNA polymerase normally present on immature lymphocytes (TdT-positive) and distinguishes ALL from mature lymphoid malignancies. We performed a multisite retrospective study to determine the incidence of TdT-negative precursor B-cell acute lymphoblastic leukemia (pre-B ALL) among Mexican, Caucasian, and US-born Hispanic children to correlate TdT expression with patient characteristics and known prognostic factors. Fisher exact test was performed for categorical variables and the Wilcoxon rank-sum test was used for continuous variables. TdT-negative pre-B ALL was most frequently identified in patients with National Cancer Institute high-risk disease ( P =0.014). TdT-negative expression was also most frequently associated with hypodiploid pre-B ALL ( P =0.001) and KMT2A gene rearrangement ( P =0.0012). Mexican children had the highest incidence of TdT-negative ALL compared with Caucasians and US Hispanics ( P <0.001), with an increased incidence of poor prognostic features as well. This study demonstrates significant differences in TdT-negative expression, genomic alterations, and leukemic ploidy based on race and ethnicity.

Prevalence, Severity, and Description of Dental Anomalies in Children Treated for Acute Lymphoblastic Leukemia.

Purpose: To assess the prevalence and severity of and describe dental anomalies in children treated for acute lymphoblastic leukemia (ALL) under recent Dana-Farber Cancer Institute (DFCI) protocols. Methods: Patients aged between 14 and 25 years old having received a diag- nosis of ALL before the age of 11 years and after September 2000 received clinical and radiographic oral examinations. Results: Dental anomalies were observed in 26 (51.0 percent) of 51 subjects. Microdontia was the most prevalent dental defect (39.2 percent). Impacted permanent second molars were observed in five (9.8 percent) patients. Being age five years or younger at diagnosis significantly increased the prevalence and severity of dental anomalies (P<0.001). Conclusions: Recent DFCI protocols showed a decreased prevalence of dental disturbances. The anomalies observed may still alter the development of the dental arches and occlusion in pediatric ALL survivors. Further research is needed to confirm the association between ALL treatment and permanent second molar impaction.