Late subsequent leukemia after childhood cancer: A report from the Childhood Cancer Survivor Study (CCSS).

BACKGROUND: Subsequent short-latency leukemias are well-described among survivors of childhood cancer. However, late (5-14.9 years from diagnosis, LL) and very late (≥15 years from diagnosis, VLL) subsequent leukemias have not been well studied. We assessed risk factors, prevalence, and outcomes for LL and VLL in the Childhood Cancer Survivor Study cohort. METHODS: Subsequent leukemias, among 25,656 five-year survivors, were self-reported and confirmed by pathology review. Standardized incidence ratios (SIR) and cumulative incidences were calculated, and relative risks (RR) were estimated using Cox regression for exposures. RESULTS: Seventy-seven survivors developed subsequent leukemia, 49 survivors with LL (median time from diagnosis 7.8 years, range 5.0-14.5 years) and 28 with VLL (median time from diagnosis 25.4 years, range 15.9-42.8 years), with a cumulative incidence of 0.23% (95% CI 0.18%-0.30%) 20 years from diagnosis for all subsequent leukemias. The most common leukemia subtypes were acute myeloid leukemia, myelodysplastic syndrome, and chronic myeloid leukemia. Compared to the general population, survivors were at increased risk, for developing LL (SIR 9.3, 95% CI 7.0-12.1) and VLL (SIR 5.9, 95% CI 3.9-8.4). In multivariable relative risk analyses, cumulative epipodophyllotoxin dose >4000 mg/m2 was associated with increased risk for LL and VLL (RR 4.5, 95% CI 2.0-9.9). CONCLUSIONS: In this large series of late subsequent leukemias, survivors of childhood cancer are at increased risk, with no evidence of plateau over time. We observed most risk among survivors who received high cumulative doses of epipodophyllotoxins. Ongoing consideration for this late effect should continue beyond 10 years.

[Trends and age-period-cohort analysis of leukemia incidence in Qidong from 1972 to 2021].

Objective: To describe the epidemiological characteristics and trends of leukemia incidence in Qidong between 1972 and 2021, and provide guidelines for prevention and control measures and strategies. Methods: The cancer registry data was collected and analyzed on leukemia incidence during 1972-2021 in Qidong by sex, age and time. Crude incidence rate (CR), China age-standardized rate (ASRC), world age-standardized rate (ASRW), and average annual change percentage (AAPC) was calculated by Joinpoint software. Age-period-cohort (APC) model was used to analyze the influence of age, period and birth cohort on the changes in the incidence trend of leukemia patients. Results: From 1972 to 2021, there were 2 948 patients with leukemia in Qidong, accounting for 2.00% of all cancer new cases, CR of leukemia was 5.26/105, ASRC was 4.34/105, ASRW was 4.35/105. The truncated incidence of 35-64 years old was 5.29/105, the cumulative incidence rate between the ages of 0 and 74 years old was 0.40%, the cumulative risk was 0.40%. There were 1 608 male patients, the CR, ASRC, and the ASRW were 5.81/105, 4.88/105 and 4.85/105. The number of female patients were 1 340, and the CR, ASRC, and the ASRW were 4.71/105, 3.86/105 and 3.91/105, respectively. Temporal trends indicated significant upward trends in ASRC among both gender, males and females with AAPC values of 1.41% (P＜0.001), 1.15% (P＜0.001), and 1.73% (P＜0.001), respectively. The results of the APC model showed that the average net drift value of leukemia incidence in all age groups was 1.57% (95% CI, 1.24%-1.89%), and the highest value of local drift was 3.20% (95% CI, 1.63%-4.78%) in the 80~ years old group. The incidence of leukemia increased with age. With the passage of time, the risk of leukemia incidence increased gradually compared with the rate ratio of leukemia incidence (risk ratio [RR], 1.00) in 1992-1996, the RR of leukemia incidence increased from 0.70 during 1972-1976 to 1.57 during 2017-2021. The later the cohort was born, the greater the risk of leukemia incidence compared with the relative risk of leukemia incidence (RR, 1.00) in 1952-1956 cohort, the RR of leukemia incidence increased from 0.24 in the 1892-1896 cohort to 2.73 in the 2017-2021 cohort. Conclusions: The incidence of the leukemia has presented a rising trend in the past fifty years. Leukemia incidence increased with age, and the period and cohort effects on the risk of incidence increase. Further research is needed to investigate the risk factors related to leukemia.

Trend analysis of hematological tumors in adolescents and young adults from 1990 to 2019 and predictive trends from 2020 to 2044: A Global Burden of Disease study.

INTRODUCTION: Cancer constitutes the primary disease spectrum contributing to the Global Burden of Disease (GBD). Adolescents and young adults (AYA) aged 15-39 have received relatively less attention regarding tumor prevention, diagnosis, and treatment compared to older adults and children. This study aimed to analyze the changes in the disease burden of hematological malignancies among the global AYA over the past three decades based on the GBD database. METHODS: The changes in the disease burden of hematological malignancies were analyzed among the AYA over the past three decades based on the information from the GBD database. The future trends were predicted using the Nordpred package in R. RESULTS: Our results showed that leukemia ranked first as the leading tumor burden among AYA in 2019, but the incidence rate and mortality rate of leukemia decreased year by year, with a projected age-standardized incidence rate (ASIR) of 1.65/100,000 for females and 2.40/100,000 for males by the year 2044. In addition, the incidence of non-Hodgkin's lymphoma has been gradually increasing in recent years, with an ASIR of 1.73/100,000 from 2020 to 2024. The results may serve as a basis for developing strategies to reduce the burden of hematological malignancies in the AYA population in different regions.

Oral manifestations in pediatric patients with leukemia: A systematic review and meta-analysis.

BACKGROUND: Leukemia is the most common malignancy in pediatric patients, and it has extramedullary involvement. Oral manifestations have been reported in the literature, but to the authors' knowledge, no systematic review has presented the general prevalence of these manifestations. This review aimed to determine the prevalence of oral manifestations in pediatric patients with leukemia. TYPES OF STUDIES REVIEWED: The authors conducted a search of PubMed-MEDLINE, Embase, Latin American and Caribbean Health Sciences Literature, Web of Science, and Scopus. Additional searches were carried out in the gray literature and via hand searching of reference lists of included studies. The inclusion criteria were observational studies that investigated the prevalence and occurrence of oral lesions in pediatric patients with leukemia. Two independent reviewers collected data from the selected articles in a prepiloted Excel (Microsoft) spreadsheet. RESULTS: From 67 included studies, 79 oral manifestations were reported. The most frequent alteration in children with acute lymphoblastic leukemia during the treatment were caries (81%), with moderate certainty of evidence. The prevalence of gingivitis was 73%, oral mucositis was 50%, and lymphadenopathy was 45%, with very low certainty of evidence. After the therapy, the prevalence of dental anomalies was 61%, and the most common were enamel hypoplasia (40%), dental agenesis (22%), and microdontia (22%), presenting very low certainty of evidence. The high heterogeneity among studies contributed significantly to reduce the certainty of the evidence. PRACTICAL IMPLICATIONS: The findings of this study show that pediatric patients with leukemia have oral manifestations predominantly during and after treatment. Health care professionals must be aware of oral manifestations and refer the patients to dentists during the oncological treatment. Thus, the dentist must support pediatric patients with leukemia to help ensure a better quality of life.

Comparison of secular trends of leukemia in China and the United States from 1990 to 2021 and their projections for the next 15 years.

Background: Leukemia imposes a large healthcare burden both in China and the United States (US). The disease burden differs greatly between the two countries, but related research is limited. We explored the differences in leukemia incidence and mortality between China and the US. Methods: Data on leukemia in China and the US from 1990 to 2021 were collected from the Global Burden of Disease 2021 database. Incidence and mortality were used to estimate the disease burden, and joinpoint regression was performed to compare their secular trends. We used an age-period-cohort model to analyze the effects of age, period, and birth cohort and project future trends in the next 15 years. Results: In 2021, the age-standardized incidence rate (ASIR) and the age-standardized death rate (ASDR) of leukemia were lower in China than in the US. However, the incidence and mortality of acute lymphoblastic leukemia (ALL) was considerably higher in China. In the past decades, the ASIR showed decreased tendency in the US, while ASIR showed stable in China. The ASDR tended to decrease in both countries from 1990 to 2021. Males have higher rates of incidence and mortality than females in two countries. The age effects showed that children and older individuals have higher RRs for incidence and mortality in China, while the RRs for incidence and mortality in the US particularly increased in the older population. The disease burden of leukemia in children is obviously greater in China. The ASIRs and ASDRs of leukemia will continue to decline in the next 15 years in China and the US, with the US experiencing a more obvious downtrend. Conclusions: Over the past decades, the ASDRs in two countries both tended to decrease. And compared to the US, China had lower leukemia incidence and mortality, However, the ASIRs in China tended toward stable, which it was showed downtrend in the US. Children have obviously greater RRs for incidence and mortality in China. The incidence and mortality will decrease continuously in two countries. Effective intervention measures are needed to reduce the burden of leukemia.

Global, regional, and national burdens of leukemia from 1990 to 2019: A systematic analysis of the global burden of disease in 2019 based on the APC model.

BACKGROUND: Leukemia is the tenth most common cause of cancer death worldwide and one of the most important causes of disability. To understand the current status and changing trends of the disease burden of leukemia at the global, regional, and national levels, and to provide a scientific basis for the development of leukemia prevention and treatment strategies. METHODS: Based on open data from the Global Burden of Disease Study 2019 (GBD 2019), R software was used to calculate estimated annual percentage changes to estimate trends in the age-standardized incidence (ASIR) and the age-standardized disability-adjusted life years (DALY) rate due to leukemia and its major subtypes from 1990 to 2019. RESULTS: In 2019, globally, the number of incidences and DALYs of leukemia were 643.6 × 103 (587.0 × 103, 699.7 × 103) and 11,657.5 × 103 (10529.1 × 103, 12700.7 × 103), respectively. The ASIR (estimated annual percentage change (EAPC) = -0.37, 95%UI -0.46 to -0.28) and the age-standardized DALY rate (EAPC = -1.72, 95%UI -1.80 to -1.65) of leukemia showed a decreasing trend from 1990 to 2019. The APC model analysis showed that the age effect of leukemia risk was a "U"-shaped distribution of relative risk (RR) with increasing age from 1990 to 2019, globally. The time effect was an increase in incidence rate with increasing years but a decrease in DALY rate with increasing years. The cohort effects of both incidence and DALY rates tended to increase and then decrease with the development of the birth cohort. In 1990 and 2019, smoking, high body-mass index, occupational exposure to benzene, and occupational exposure to formaldehyde were risk factors for DALY in leukemia, especially in areas with high SDI. CONCLUSIONS: From 1990 to 2019, the disease burden of leukemia showed a decreasing trend, but it is worth noting that its overall severity is still very high. The disease burden of leukemia varies greatly from region to region, and exclusive strategies for the prevention and treatment of leukemia should be developed according to the economic and cultural development of each region.

Evaluating exposure-response relationship in 1,3-butadiene and leukemia studies.

OBJECTIVES: 1,3-Butadiene (BD) exposure's link to leukemia is under regulatory scrutiny. The assessment methods for BD exposure risks have evolved from early animal and limited human studies to advanced exposure-response modelling with comprehensive quantitative data. The objec- tive of this study is to explore the nuances of exposure-response modelling, investigating how various statistical methods have influenced the quan- tification of exposure-response relationships. MATERIAL AND METHODS: Although this study was not conducted as a formal systematic review, a search was performed in Medline/Pubmed to identify all human studies on leukemia risk assessment for BD exposure. This search included articles written in English. The electronic search spanned from inception of records until July 23, 2023, using the search term: "butadiene AND (leukaemia OR leukemia OR myeloid OR lymphoid)" and was restricted to human species. Focusing on the synthetic styrene-butadiene rubber (SBR) industry cohort study conducted by the University of Alabama at Birmingham, USA, this review evaluates various statistical models and factors influenc- ing exposure-response modelling. RESULTS: Peak exposures to BD may be more influential in the dose-response relationship than cumulative or long-term exposure. The authors recommend utilizing ß-coefficients derived from the latest SBR study update, employing Cox proportional hazard modelling, non-lagged and non-transformed cumulative BD exposure, and adjusting for age and peak BD exposure. The study reveals that statistical model selection has a limited impact on the calculated dose-response effects. The significant variation in estimated cancer mortality values arises from additional assumptions needed for metrics like the excess leukemia risk or the occupational BD effective concentration. CONCLUSIONS: In con- clusion, this study provides insights into exposure-response modelling for BD exposure and leukemia mortality, highlighting the importance of peak exposures. The recommended statistical approach offers a reliable basis for regulatory risk assessment and public health population metrics. Int J Occup Med Environ Health. 2024;37(3):300-10.

Leukemia Incidence by Occupation and Industry: A Cohort Study of 2.3 Million Workers from Ontario, Canada.

Although a significant body of evidence has attributed certain occupational exposures with leukemia, such as benzene, formaldehyde, 1,3-butadiene and ionizing radiation, more research is needed to identify work environments at increased risk for this disease. Our study aimed to identify occupational and industry groups associated with an elevated incidence of leukemia using a diverse cohort of workers' compensation claimants from Ontario, Canada. A total of 2,363,818 workers in the Occupational Disease Surveillance System (ODSS) cohort, with claims between 1983-2019, were followed for malignant leukemia diagnoses up to 31 December 2019. We used a Cox proportional-hazards model to estimate the relative incidence of leukemia in specific occupation and industry groups. After adjusting for age and birth year, males in protective services (HR = 1.17, 95% CI = 1.02-1.35), metal machining (HR = 1.23, 95% CI = 1.07-1.41), transport (HR = 1.15, 95% CI = 1.06-1.25), and mining occupations (HR = 1.28, 95% CI = 1.02-1.60) had elevated risks of leukemia compared to other workers in the ODSS, with comparable findings by industry. Among female workers, slight risk elevations were observed among product fabricating, assembling, and repairing occupations, with other increased risks seen in furniture and fixture manufacturing, storage, and retail industries. These findings underscore the need for exposure-based studies to better understand occupational hazards in these settings.

Benzene exposure and pediatric leukemia: From molecular clues to epidemiological insights.

According to the International Agency for Research on Cancer, leukemia ranks 14th in incidence and 11th in mortality and has a 5-year prevalence of approximately 1300,000 cases. Acute lymphoblastic leukemia is the most common hematopoietic syndrome in children during the first 5 years of life and represents approximately 75 % of all neoplasms among the pediatric population. The development of leukemia is strongly governed by DNA alterations that accelerate the growth of bone marrow cells. Currently, the most examined factor in pediatric leukemia is exposure to multiple compounds, such as hydrocarbons. Benzene, an aromatic hydrocarbon, can cause health challenges and is categorized as a carcinogen. Benzene toxicity has been widely associated with occupational exposure. Importantly, studies are underway to generate evidence that can provide clues regarding the risk of environmental benzene exposure and hematological problems in children. In this review, we summarize the existing evidence regarding the effects of benzene on pediatric leukemia, the associations between the effect of benzene on carcinogenesis, and the presence of certain molecular signatures in benzene-associated pediatric leukemia. Although there is sufficient evidence regarding the effects of benzene on carcinogenesis and leukemia, epidemiological research has primarily focused on occupational risk. Moreover, most benzene-induced molecular and cytogenetic alterations have been widely described in adults but not in the pediatric population. Thus, epidemiological efforts are crucial in the pediatric population in terms of epidemiological, clinical, and biomedical research.

Global burden, risk factor analysis, and prediction study of leukaemia from 1990 to 2030.

Background: Leukaemia is a devastating disease with an incidence that progressively increases with advancing age. The World Health Organization has designated 2021-30 as the decade of healthy ageing, highlighting the need to address age-related diseases. We estimated the disease burden of leukaemia and forecasted it by 2030. Methods: Based on the Global Burden of Disease 2019 database, we systematically analysed the geographical distribution of leukaemia and its subtypes. We used Joinpoint regression and Bayesian age-period-cohort models to evaluate incidence and mortality trends from 1990 to 2019 and projections through 2030. We analysed five leukaemia subtypes and the impact of age, gender, and social development. Decomposition analysis revealed the effects of disease burden on ageing and population growth. We used frontier analysis to illustrate the potential of each country to reduce its burden based on its development levels. Results: Globally, the absolute numbers of leukaemia incidence and mortality have increased, while the age-standardised rates (ASRs) have shown a decreasing trend. The disease burden was more pronounced in men, the elderly, and regions with a high socio-demographic index (SDI), where ageing and population growth played varying roles across subtypes. From 2000 to 2006, disease burdens were most effectively controlled. Global ASRs of incidence might stabilise, while ASRs of death are expected to decrease until 2030. Frontier analysis showed that middle and high-middle SDI countries have the most improvement potential. Smoking and high body mass index were the main risk factors for leukaemia-related mortality and disability-adjusted life years. Conclusions: The absolute number of leukaemia cases has increased worldwide, but there has been a sharp decline in ASRs over the past decade, primarily driven by population growth and ageing. Countries with middle and high-middle SDI urgently need to take action to address this challenge.

Wood dust and risk of leukemia: Systematic review and meta-analysis.

OBJECTIVES: This study aimed to perform a systematic review and meta-analysis to investigate the relationship between wood dust exposure and leukemia. The objectives included synthesizing available evidence, assessing its quality, identifying potential sources of heterogeneity, and drawing conclusions regarding the association between wood dust and leukemia. METHODS: A systematic literature search was conducted to identify studies meeting that report on the association between wood dust and leukemia. The Joanna Briggs Institute Critical Appraisal tools were employed to ensure robust quality assessment. Meta-analysis, using random-effects models, synthesized evidence from studies with low risk of bias. Overall odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Subgroup analyses explored potential sources of heterogeneity. RESULTS: The meta-analysis included a comprehensive review of various study types, encompassing 7 studies that examined the association between wood dust exposure and leukemia risk. The analysis revealed a statistically significant positive association, with an overall odds ratio (OR) of 1.56 (95% CI: 1.15-2.12). This indicates that individuals exposed to wood dust are 1.56 times more likely to develop leukemia compared to those not exposed, with the 95% confidence interval ranging from 1.15 to 2.12, highlighting a substantial risk elevation across different study designs. Quality assessment using The Joanna Briggs Institute Critical Appraisal tools demonstrated a low risk of bias across all included studies, enhancing the credibility of the observed association. Subgroup analyses were conducted to explore potential sources of heterogeneity within the studies. Notably, subgroup analysis based on the year of the study revealed significant differences, as indicated by an I^2 value of 87%. The robustness of these results underscores the importance of addressing wood dust exposure as an occupational hazard, particularly in industries related to woodworking and forestry. CONCLUSION: This meta-analysis provides robust evidence supporting an increased risk of leukemia associated with wood dust exposure implying proactive measures in people exposed to dust.

Patterns of the Leukemia Records that were Referred to the Regional Laboratory in Makkah, Saudi Arabia.

BACKGROUND: Leukemia is the fifth most common cancer in Saudi Arabia. The aim of this study was to assess the various patterns of leukemia associated with age, gender, and nationality in this region. METHODS: This cross-sectional study was conducted at the regional laboratory in Makkah, Saudi Arabia, from April to November 2023. Descriptive statistics were presented as frequencies and percentages by using the GraphPad Prism software. RESULTS: This study included 107 patients, and the results showed that leukemia cases were higher in males than females and more prevalent in older patients (above 50 years of age). Overall, acute myeloid leukemia (AML) and acute lymphocytic leukemia (ALL) were the most common types of leukemia among Saudi patients. In addition, AML was the most prevalent type of leukemia in males and females, followed by ALL. Data also revealed that ALL was the most common type in the younger population, whereas AML was highly prevalent in older patients. CONCLUSIONS: In conclusion, this study provides valuable information about the patterns of leukemia reported at the regional laboratory in Makkah and will help in designing management and preventive approaches for these patients. This epidemiological investigation is also valuable for establishing proper medical databases.

Potential Associations Between Vitamin Intake and Leukemia: A Cross-Sectional Study.

The present study assessed potential associations between vitamin intake and leukemia in a national sample of adults in the United States. A total of 5520 participants were included in this cross-sectional study to investigate the relationship between vitamin intake (including vitamins A, C, D, and E) and leukemia. Results revealed negative associations between vitamin C and E intake and leukemia, whereas associations between vitamin A and D and leukemia were not statistically significant. For vitamin C, compared with the first tertile, the odds ratio (OR) and corresponding 95% confidential interval (CI) was 0.90 (0.75-0.95) for the second tertile and 0.82 (0.61-0.90) for the third tertile (p < 0.01). For vitamin E, compared with the first tertile, the OR and 95% CI was 0.92 (0.80-0.96) for the second tertile and 0.86 (0.71-0.92) for the third tertile (p < 0.01). Furthermore, the inverse relationship between intake of vitamins C and E and leukemia were more evident for individuals ≥60 years of age and those with a body mass index >30 kg/m2. Results of this study provide evidence suggesting that intake of vitamin C and E intake may decrease the prevalence of leukemia; however, further large-scale prospective cohort studies are needed to verify these findings.

Breastfeeding Duration Reduces the Risk of Childhood Leukemia and Modifies the Risk of Developing Functional Gastrointestinal Disorders.

Objective: The aim of this study was to test the hypothesis that the duration of breastfeeding in infancy reduces the risk of childhood leukemia or lymphoma, and modifies the risk of developing functional gastrointestinal disorders (FGIDs). Subjects and Methods: This case-control study involved the recruitment of children with lymphoid malignancy and functional gastrointestinal symptoms with healthy children as controls. Focused questionnaires were used to collect data on breastfeeding history and other key risk factors. Univariate and multivariate analyses were undertaken. Results: Of the 334 children with lymphoid malignancy, 65% were male. The control group included 334 age- and sex-matched participants. Most (n = 189; 56.6%) of the children with leukemia were <10 years of age. Differences between cases and controls included the duration of breastfeeding (p < 0.0001), mean birthweight (p < 0.001), maternal age (p < 0.001), paternal age (p < 0.001), birth order (p < 0.001), mean number of children (p < 0.001), BMI percentile (p = 0.042), and maternal smoking (p = 0.012). Breastfeeding duration of up to 6 months' duration, when compared with feeding of longer than 6 months, was associated with increased odds ratios (OR) for acute lymphoblastic leukemia (OR = 3.43, 95% confidence interval [CI] 2.37-4.98; p < 0.001), Hodgkin's lymphoma (OR = 1.58, 95% CI: 0.88-2.84, p = 0.120), Non-Hodgkin's lymphoma (OR = 2.14, 95% CI: 1.25-3.65, p = 0.005), and overall (OR = 1.95, 95% CI: 1.40-2.71, p < 0.001). Cases also differed from controls with regard to FGIDs, such as stomach ache (p < 0.001), dyspepsia (p < 0.001), early satiety (p = 0.017), bowel satisfaction (p < 0.001), bloating (p < 0.001), nausea (p = 0.005), vomiting (p = 0.039), constipation (p = 0.003), diarrhea (p = 0.010), gastrointestinal canal congestion (p =0.039), muscle aches pains (p = 0.008), fecal incontinence (p = 0.021), and indigestion (p = 0.003). A multivariate stepwise regression analysis revealed that maternal smoking (p < 0.001), formula feeding (p < 0.001), duration of breastfeeding (p < 0.001), birth order (p = 0.002), mother's age (p = 0.004) and the child's birthweight (p = 0.009) were predictors for leukemia. Further analysis showed that dyspepsia (p < 0.001), gastrointestinal tract canal congestion (p < 0.001), constipation (p = 0.009), diarrhea (p = 0.013), bowel satisfaction (p = 0.021), bloating (p = 0.022), duration of breastfeeding (p < 0.001), and stomach ache (p = 0.025) were significant predictors for developing FGID symptoms after adjusting for age, gender, and other confounding variables. Conclusion: This study confirmed that breastfeeding has some effect on reducing possible risk of childhood lymphoma and leukemia and FGID symptoms compared with healthy control children.

Global incidence and mortality of childhood leukemia and its relationship with the Human Development Index.

BACKGROUND: Childhood leukemia (CL) is a major global concern, accounting for 33% of all new cancer cases and 31% of all cancer deaths in children aged 0-14 years. Our study aimed to analyze the global incidence and mortality rates of CL in 2020 and its relationship with the Human Development Index (HDI). MATERIAL AND METHODS: In this ecologic study, we analyzed the 2020 cancer incidence and mortality data for children aged 0-14 years from the GLOBOCAN Project. We calculated the Age-Standardized Incidence Rate (ASIR) and Age-Standardized Mortality Rate (ASMR) of CL per 100,000 individuals. Pearson's correlation coefficient was used to examine the association between childhood leukemia ASIR, ASMR, and the HDI, with a statistical significance threshold of P<0.05. RESULTS: In 2020, there were a total of 67,008 new cases of CL worldwide, with males accounting for 57.85%. The global ASIR for CL was 3.4 per 100,000 (3.9 in males, 3 in females). Additionally, there were 25,080 CL-related deaths, with males comprising 58.86%. The overall ASMR for CL was 1.3 (1.4 in males, 1.1 in females). We found a significant positive correlation (r = 0.405, P≤0.001) between the global ASIR and ASMR for CL. There was a strong positive correlation (r = 0.770, P = 0.001) between the HDI and childhood leukemia ASIR, but no significant association (r = 0.077, P = 0.337) was observed with ASMR. CONCLUSION: Our study reveals that CL remains a significant health burden worldwide. We identified a positive correlation between the ASIR of CL and the HDI, indicating a potential role of socioeconomic factors in CL incidence.

Cancer incidence in Swedish oil refinery workers exposed to benzene.

BACKGROUND: Oil refinery workers are exposed to benzene, which is a well-known cause of leukaemia, but results on leukaemia in oil refinery workers have been mixed, and the data on workers' exposure is limited. Oil refinery workers are also exposed to asbestos and several studies have shown increased risk of mesothelioma. AIM: The objective was to investigate cancer incidence, especially leukaemia, at low to moderate exposure to benzene in an update of a previous study of employees at three Swedish oil refineries. METHODS: Cancer incidence was followed up in 2264 men (1548 refinery operators) employed at three oil refineries in Sweden for at least one year. Job types and employment times were collected from complete company files. A retrospective assessment of the benzene exposure was performed by occupational hygienists in collaboration with the refineries using historic measurements as well as detailed information on changes in the industrial hygiene and technological developments. Cases of cancer were retrieved by a linkage with the Swedish Cancer Register through 35-47 years of follow-up and standardized incidence ratios (SIR) with 95% confidence intervals (CI) were calculated. RESULTS: In total, 258 tumors had occurred versus 240 expected (SIR 1.07; 95% CI 0.95-1.21). There were 10 cases of leukaemia, all in refinery operators (SIR 2.4; 95% CI 1.18-4.51). There were three cases of pleural mesothelioma, two of which in refinery operators. The mean estimated cumulative benzene exposure for the cases of leukaemia was 7.9 ppm-years (median 4.9, range 0.1-31.1). DISCUSSION: The study suggests that low to moderate average cumulative benzene exposure increases the risk of leukaemia. Limitations include the modest number of cases and potential misclassification of exposure. CONCLUSION: The present study indicated an increased risk of leukaemia in male oil refinery workers with low to moderate exposure to benzene.

Comparative analysis of leukemia and risk estimation in working age population between provinces of Ecuador.

Leukemia is associated with exposure to radiation, benzene derivatives, and pesticides. Previous research has documented an increase in work-related leukemia in the Latin American Andean region. To date, there are only few studies in Ecuador on the impact of oil exploitation on adjacent indigenous communities. Our study aims to show the impact of leukemia on the working-age population. For the calculation of morbidity and mortality rates, we used hospital discharge and death records from the National Institute of Statistics of Ecuador. These data were collected and adjusted to the corresponding province's population for further analysis. Large differences were observed between provinces in adjusted rates of leukemia mortality and morbidity in the working-age population. The variations in altitude among different areas in Ecuador give the provinces a distinct geographic identity. Likewise, the provinces with the highest morbidity and mortality rankings, such as Azuay, Loja, Imbabura, and Tungurahua, have an average altitude above 2000 meters. As a result, there are variations in the average temperature, exposure to solar and cosmic radiation, and mining and farming methods. The observed differences warrant the future collection of geolocation data for affected individuals. This could help to better understand how leukemia cases have demogrpahic hotspots in the country, identify possible risk factors associated with the disease in each region, and design more effective prevention and control strategies.

La leucemia es una enfermedad a consecuencia, además de factores genéticos, de la exposición a radiaciones, derivados del benceno y pesticidas. Investigaciones anteriores han documentado un aumento de la leucemia ocupacional en la región andina de América Latina. Hasta la fecha, existen sólo unos pocos estudios en Ecuador sobre el impacto de la explotación petrolera en las comunidades indígenas. Nuestro objetivo es mostrar el impacto de la leucemia en la población en edad de trabajar. Para el cálculo de las tasas de morbimortalidad se utilizaron los registros de altas hospitalarias y defunciones del Instituto Nacional de Estadística del Ecuador. Estos datos fueron recopilados y estimadas las tasas ajustadas. Se observaron grandes diferencias entre provincias en las tasas ajustadas de mortalidad y morbilidad por leucemia en la población en edad de trabajar. Asimismo, las provincias con mayor ranking de morbilidad y mortalidad, como Azuay, Loja, Imbabura y Tungurahua, coinciden en tener una altitud promedio superior a los 2000 metros. Hay provincias de baja altitud en la costa y provincias por encima de los 2000 metros en la sierra, lo que le da a las provincias del Ecuador una identidad geográfica distintiva. Como resultado, existen variaciones en la temperatura promedio, la exposición a la radiación solar y cósmica, y actividades de minería y agricultura. Las diferencias observadas, recomiendan la recopilación futura de datos de geolocalización de las personas afectadas. Esto podría ayudarnos a comprender mejor cómo se distribuyen los casos de leucemia, identificar posibles factores de riesgo asociados a la enfermedad en cada región y diseñar estrategias de prevención y control más efectivas.

Risk of Lymphoma and Leukemia in Thyroid Cancer Patients: A Retrospective Cohort Study in Germany.

Thyroid cancer is the ninth most common cancer worldwide. While differentiated thyroid cancer (DTC) has a high survival rate, concerns arise regarding optimal treatment strategies and potential long-term risks, including second primary malignancies (SPMs), associated with therapies such as radioiodine (RAI). The aim of the present study was to investigate the association between thyroid cancer and the incidence of subsequent lymphoma and leukemia in Germany. This retrospective cohort study used the IQVIA TM Disease Analyzer database and included adults with a first documented diagnosis of thyroid cancer between January 2005 and December 2021 as well as propensity score matched individuals without thyroid cancer in 1284 general practices. Univariate Cox regression models were performed to examine the association between thyroid cancer and the incidence of subsequent lymphoma and leukemia. A total of 4232 thyroid cancer patients (mean age: 54.2 years; 73.6% female) and 21 160 controls (mean age: 54.2 years; 72.6% female) were available for analyses. Thyroid cancer was significantly associated with a higher lymphoma incidence (HR: 3.35, 95% CI: 2.04-5.52), especially in men (HR: 5.37) and those aged 61-70 years. Leukemia incidence was not significantly associated with thyroid cancer (HR: 1.79, 95% CI: 0.91-3.53), although associations were notable in younger age groups. Thyroid cancer is positively associated with a risk of subsequent lymphoma, highlighting the need for vigilant surveillance and tailored treatment strategies. While the association with leukemia is less pronounced, close surveillance remains critical, especially in younger patients.

Leukemia Types and Subtypes Analysis: Epidemiological Age-Standardized Exploration in the Mexican Bajio Region.

Background and Objectives: Leukemia, characterized by abnormal leukocyte production, exhibits clonal origin from somatic mutations. Globally, it ranked 15th in cancer incidence in 2020, with higher prevalence in developing countries. In Mexico, it was the ninth most frequent cancer. Regional registries are vital for understanding its epidemiology. This study aims to analyze the prevalence and age-standardized incidence rates of leukemias in a tertiary care hospital in the Mexican Bajio region. Materials and Methods: Leukemia cases from 2008-2018 were analyzed, and 535 medical records were included in this study. The prevalence, distribution, and age-specific incidence rate of different types and subtypes of leukemia were determined according to sex and age groups. Results: Overall, 65.79% consisted of lymphocytic leukemia, 33.64% of myeloid leukemia, and 0.56% of monocytic leukemia. No significant sex-based differences were found, but age-specific patterns were observed. Leukemia distribution by age revealed significant associations. Lymphocytic leukemia dominated in the pediatric population, particularly acute lymphocytic leukemia, while myeloid leukemia shifted towards adulthood. Age-specific incidence patterns showed, first, that lymphocytic leukemia is the most common leukemia in pediatric ages, and second, there is a shift from acute lymphocytic leukemia dominance in pediatric ages to myeloid leukemia incidence in late adulthood, emphasizing nuanced epidemiological dynamics. Conclusions: Acute leukemia cases occurred with high prevalence in our study population, with a high incidence in pediatric and adulthood populations, especially for acute lymphocytic leukemia, showing a (<18 years) 153.8 age-standardized incidence rate in the pediatric group, while in the adult population, the age-standardized rate was 59.84. In the age-specific analysis, we found that the childhood group (5-9 years) were the most affected by acute lymphocytic leukemia in the pediatric population, while in the adult population, the early-adulthood group (15-29 years) were the most affected age group. In contrast, chronic myeloid leukemia affected both adults and the pediatric populations, while chronic lymphocytic leukemia and monocytic leukemia were exclusive to adults. The study underscores the need for tailored diagnostic, treatment, and preventive strategies based on age, contributing valuable insights into the leukemia epidemiology of the Bajio region.

Trends in childhood leukemia incidence in urban countries and their relation to environmental factors, including space weather.

Leukemia is the most common cancer in children. Its incidence has been increasing worldwide since 1910th, suggesting the presence of common sources of the disease, most likely related to people's lifestyle and environment. Understanding the relationship between childhood leukemia and environmental conditions is critical to preventing the disease. This discussion article examines established potentially-carcinogenic environmental factors, such as vehicle emissions and fires, alongside space weather-related parameters like cosmic rays and the geomagnetic field. To discern the primary contributor, we analyze trends and annual variations in leukemia incidence among 0-14-year-olds in the United States, Canada, Australia, and Russia from 1990 to 2018. Comparisons are drawn with the number of vehicles (representing gasoline emissions) and fire-affected land areas (indicative of fire-related pollutants), with novel data for Russia introduced for the first time. While childhood leukemia incidence is rising in all countries under study, the rate of increase in Russia is twice that of other nations, possibly due to a delayed surge in the country's vehicle fleet compared to others. This trend in Russia may offer insights into past leukemia levels in the USA, Canada, and Australia. Our findings highlight vehicular emissions as the most substantial environmental hazard for children among the factors examined. We also advocate for the consideration of potential modulation of carcinogenic effects arising from variations in cosmic ray intensity, as well as the protective role of the geomagnetic field. To support the idea, we provide examples of potential space weather effects at both local and global scales. The additional analysis includes statistical data from 49 countries and underscores the significance of the magnetic field dip in the South Atlantic Anomaly in contributing to a peak in childhood leukemia incidence in Peru, Ecuador and Chile. We emphasize the importance of collectively assessing all potentially carcinogenic factors for the successful future predictions of childhood leukemia risk in each country.