Secular trends in the incidence and survival of all leukemia types in the United States from 1975 to 2017

Metabolic determinants of leukemia onset variability in genetically homogeneous AKR mice

Leukemia is a complex disease shaped by the intricate interplay of genetic and environmental factors. Given our preliminary data showing different leukemia incidence in genetically homogenous AKR mice harboring the spontaneous leukemia-inducing mutation Rmcfs, we sought to unravel the role of metabolites and gut microbiota in the leukemia penetrance. Our metabolomic analysis revealed distinct serum metabolite profiles between mice that developed leukemia and those that did not. We discovered that linoleic acid (LA), an essential ω-6 polyunsaturated fatty acid, was significantly decreased in the leukemia group, with the lower levels observed starting from 25 weeks before the onset. A predictive model based on LA levels demonstrated high accuracy in predicting leukemia development (area under curve 0.82). In vitro experiment confirmed LA's cytotoxic effects against leukemia cells, and in vivo study showed that a diet enriched with LA prolonged survival in AKR mice. Furthermore, gut microbiome analysis identified specific Lachnospiraceae species, that affect host lipid metabolism, are exclusively present in the leukemia group, suggesting their potential influence on LA metabolism and leukemia development. These findings shed light on the complex relationship between metabolites, gut microbiota, and leukemia development, providing valuable insights into the role of non-genetic factors in leukemia penetrance and potential strategies for leukemia prevention.

Secular trend in disease burden of leukemia and its subtypes in China from 1990 to 2019 and its projection in 25 years

Leukemia and its subtypes impose a major public health challenge in China. Identifying the secular trend of leukemia burden is critical to facilitate optimal healthcare planning and improve the management of leukemia. The incidence rates of leukemia from 1990 to 2019 were collected from the Global Burden of Disease Study 2019 database according to the following: subtype (acute lymphocytic leukemia [ALL], acute myeloid leukemia [AML], chronic lymphocytic leukemia [CLL], chronic myelogenous leukemia [CML], and other leukemia subtypes), sex, and age group. The average annual percentage changes and relative risks were calculated using joinpoint regression and the age-period-cohort model, respectively. The Bayesian age-period-cohort model was also applied to predict the future trend of the incidence of leukemia and its subtypes in the next 25 years. From 1990 to 2019, the age-standardized incidence rates (ASIRs) of leukemia slightly declined in males and females, which is similar to the trend of other leukemia subtypes. However, the four major leukemia subtypes, namely, ALL, AML, CLL, and CML, have been on the rise over the past three decades. The incidence rates of leukemia in children and the elderly were considerably higher than those in other age groups in males and females. Age effects were the most influential risk factor for leukemia incidence. Period effects showed that the risks of leukemia and its subtypes incidence increased with time. For cohort effects, the risks of leukemia and its subtypes were higher among the early-born cohorts compared with the late-born cohorts. The ASIRs of leukemia and its subtypes will continue to increase in the next 25 years. The burden of leukemia and its subtypes is expected to continue to increase in the next 25 years in males and females. A comprehensive understanding of the risk characteristics and disease pattern of leukemia and its subtypes is needed to formulate timely and effective intervention measures to reduce the leukemia burden in China.

Epidemiology of Chronic Lymphocytic Leukemia in Sardinia, Italy (1974-2003)

Several reports have described a worldwide increasing incidence of chronic lymphocytic leukemia (CLL) dating back seven to eight decades. Although genetic susceptibility would be an implausible explanation, the determinants of this upward trend and its spatial coordinates are poorly understood. We explored CLL incidence in Sardinia, Italy, using a validated database including the 1700 CLL cases diagnosed during 1974-2003. We applied Bayesian methods to map the CLL probability by administrative unit and Poisson regression analysis to investigate socioeconomic and environmental determinants adjusting by possible confounders. The standardized (Standard European population) incidence rate for the Sardinian population over the study period was 5.1 per 100,000 (95% confidence interval [CI] 4.9-5.3), increased annually by 5.8% (95% CI 5.7-6.0) consistently by sex and age, and was more noticeable in urban areas. Five administrative units exceeded the 95% posterior probability of an elevated CLL incidence: these were rural areas spread over the regional territory, not suggestive of spatial clustering. The Poisson regression analysis showed that the risk was elevated in urban areas (RR = 1.11, 95% CI 1.05-1.17), among residents ≥ 30 km from the nearest hospital (RR = 1.09, 95% CI 1.06-1.12), and with the local prevalence of cork harvesting (RR = 1.62, 95% CI 1.12-2.34). Our results suggest that better access to health care facilities and improvements in diagnostic efficacy might have generated the observed upward trend in CLL incidence, along with contributing environmental factors.

Gender differences in leukemia outcomes based on health care expenditures using estimates from the GLOBOCAN 2020

BACKGROUND

Leukemia contributes significantly to the global cancer burden. Due to the importance of evaluating improvements in leukemia outcomes, the current study aimed to examine the variations in mortality-to-incidence ratio (MIR) between genders and association of MIR with the health expenditures in selected countries.

METHODS

The leukemia incidence and mortality rates were extracted from the GLOBOCAN 2020 database. In total, 56 countries were included based on the data quality reports and the exclusion of missing data. The associations of MIR and changes in MIR over time ([Formula: see text]MIR) with the human development index (HDI), current health expenditure (CHE) per capita, and current health expenditure as a percentage of gross domestic product (CHE/GDP) were investigated using Spearman's rank correlation coefficient.

RESULTS

In 2020, an estimated 474,519 new cases of leukemia were diagnosed globally, and 311,594 deaths occurred due to the disease. Male patients exhibited a higher incidence and mortality of leukemia compared to females on a global scale. Our analysis revealed that the MIRs were the highest and lowest in Egypt (0.79) and the United States (0.29), respectively. Remarkably, countries with greater HDI, higher CHE per capita, and a higher CHE/GDP tended to have lower MIR in both genders and within gender-specific subgroups. The δMIR demonstrated a significant negative correlation with HDI and CHE per capita, whereas no significant associations were observed among female patients for CHE/GDP. Besides, all three indicators showed trends towards negative correlations with δMIR among males, though these trends were not statistically significant (p>0.05).

CONCLUSIONS

Generally, leukemia MIRs tended to be most favorable (i.e., lower) in countries with high HDI and high health expenditure. The gender differences observed in leukemia outcomes may reflect the potential influence of social, material, behavioral, and biological factors.

Incidence and Bayesian Mapping of Myeloid Hematologic Malignancies in Sardinia, Italy

BACKGROUND

The epidemiology of myeloid hematologic malignancies in Italy has been poorly investigated.

METHODS

We used a validated database of 1974-2003 incident cases of hematologic malignancies among the resident population (all ages) of Sardinia, Italy, to describe the incidence of myeloid malignancies overall (N = 4389 cases) and by subtype. We investigated the time trend of acute myeloid leukemia (N = 1227 cases), chronic myeloid leukemia (N = 613 cases), and myelodysplastic syndrome (N = 1296 cases), and used Bayesian methods to explore their geographic spread, and Poisson regression analysis to estimate their association with environmental and socio-economic factors.

RESULTS

The annual standardized (world population) incidence rate (IR) of myeloid malignancies over the study period was 6.5 per 100,000 (95% CI 6.2-6.7). Myelodysplastic syndromes were the most prevalent subgroup (IR = 1.7, 95% CI 1.5-1.8). Incidence of all myeloid malignancies combined increased sharply during the study period with an annual percent change (APC) of 10.06% (95% CI 9.51-10.61), 19.77% for myelodysplastic syndromes (95% CI 19.63-19.91), and 3.18% (95% CI 2.99-3.37) for acute myeloid leukemia. Chronic myeloid leukemia did not show an upward trend. Apart from sporadic excesses in small rural communities and the major urban area, there was no evidence of spatial clustering. The risk of myeloid malignancies increased with increasing prevalence of sheep breeding.

CONCLUSIONS

Our results might prompt further research on the local genetic and environmental determinants of myeloid hematologic malignancies.

Regional and national burden of leukemia and its attributable burden to risk factors in 21 countries and territories of North Africa and Middle East, 1990-2019: results from the GBD study 2019

PURPOSE

Regional and national data on leukemia's burden provide a better comprehension of leukemia's trends and are vital for policy-makers for better allocation of the resources. This study reports the burden of leukemia, and the attributed burden to its risk factors in 21 countries and territories of the North Africa and Middle East.

METHODS

Data from cancer registration, scientific literature, survey, and reports were the input to estimate the burden of leukemia. In addition, the burden of attributable risk factors with evidence of causation with leukemia was calculated using the comparative risk assessment framework. All measures are reported as counts and rates divided by sex and specific age groups.

RESULTS

In 2019, there were 39,297 (95% uncertainty interval: 32,617-45,056) incident cases of leukemia with an age-standardized rate (ASR) of 7.8 (6.5-8.8) per 100,000 in the region. There were also 25,143 (21,109-28,826) deaths and 1,011,555 (822,537-1,173,621) DALYs attributed to Leukemia with an ASR of 5.4 (4.6-6.1) per 100,000 and 183.4 (150.7-211.2) per 100,000, respectively. Years of life lost (YLLs) (179.4 [147.2-206.7]) were accountable for the major part of DALYs. All count measures increased, while all the ASRs decreased during 1990-2019. The Syrian Arab Republic, Qatar, and Afghanistan had the highest ASR incidence, mortality, and DALYs rate in 2019. Incidence, DALYs, and prevalence rates were higher in males of all age groups except under five, and the highest rates were observed in +75 age group. Four major risk factors for leukemia were smoking, high body mass index, occupational exposure to benzene, and formaldehyde.

CONCLUSION

Despite the reduction in age-standardized rates of incidence and mortality, the burden of leukemia has increased steadily, due to population growth and aging. Notable variations exist between age-standardized rates in region's countries.

Burden of All Cancers Along With Attributable Risk Factors in China From 1990 to 2019: Comparison With Japan, European Union, and USA

Background

Understanding the epidemiological characteristics of various cancers can optimize the prevention and control strategies in the national cancer control plan. This study aimed to report the burden differences, pattern trend, and potential risk factors of all neoplasm types in China in recent 30 years, and further compared with top economies in the world.

Methods

The disability-adjusted life-years (DALYs) and age-standardized DALY rate (ASDR) of all neoplasms with the attributable risk factors from 1990 to 2019 in China, Japan, European Union, USA, and the world were extracted from the Global Burden of Disease Study 2019. The temporal trend analysis was estimated using the joinpoint regression model.

Results

In 2019, about 251.4 million DALYs worldwide were caused by all neoplasms, and nearly 26.9% (67.5 million DALYs) occurred in China with the ASDR in 2019 of 342.09/10 000, which was higher than European Union (334.25/10 000), USA (322.94/10 000), and Japan (250.36/10 000). Although the cancer burden of the colorectum, non-Hodgkin lymphoma, oral cavity, ovary, and kidney in China was lower than in Japan, European Union and USA, the corresponding ASDR gradually increased in China over the past 30 years, but declined in the three developed areas. Around 46.29% of overall neoplasms DALYs in China in 2019 were attributed to 22 identified risk factors, and the specific risk attributable-fraction for several neoplasm types varied greatly in these regions.

Conclusion

The ASDR of cancers of the lung, colorectum, pancreas, non-Hodgkin lymphoma, oral cavity, ovary, kidney, and chronic lymphoid leukemia increased in China compared to 30 years ago. With the population aging and the social transformation in China, the increasing burden of neoplasms and the changing spectrum of neoplasms suggest that effective comprehensive prevention and treatment measures should be adopted to reduce the burden, including public health education, strict tobacco-control policy, healthier lifestyles, along with expanding vaccination programs and early cancer screening.