The use of cosmetics, personal care and cleaning products during pregnancy: a cross-sectional study

This study was planned to determine the use of cosmetics, personal care and cleaning products containing chemicals during pregnancy and the affecting factors. The study is quantitative, descriptive and cross-sectional. The sample size was calculated using the G*Power program. 287 puerperant women were reached. Data were obtained with the Introductory Information Form and Cosmetic and Chemical Product Usage Form. In the study, number and percentage values were given and chi-square and regression analysis were performed. In cosmetics and personal care products, shampoo, toothpaste and deodorant/perfume are among the top three most commonly used products, while dishwashing detergent, laundry detergent and bleach are among the cleaning products. The products that are most restricted in use are hair dye and descaling. It has been determined that education level, occupation, income and number of pregnancies are effective in the use of some products. Taking measures to protect pregnant women is important for improving maternal and newborn health.

Maternal autoimmune disease and offspring risk of haematological malignancies: a case-control study

Background

Autoimmune diseases are known to be associated with an increased risk of cancer. Whether maternal immune dysregulation can have an impact on the development of haematological malignancies in offspring remains uncertain. Therefore, we explored the association between offspring risk of haematological malignancies and maternal autoimmune disease using a real-world nationwide population-based study.

Methods

In this case-control study, we identified 2172 children with haematological malignancies between 2004 and 2019 from Taiwan's National Health Insurance program and compared them with population-based controls without haematologic malignancies, who were matched with each individual at a ratio of 1:4. The medical information of the autoimmune mothers were obtained from the Taiwan Maternal and Child Health Database. Conditional logistic regression was used to estimate the odds ratio for haematologic malignancy in offspring. Furthermore, subgroup and stratified analyses were conducted.

Findings

Among the rheumatologic diseases in our study, Crohn's disease was the most common disease both in the haematological malignancy group (1.1%) and the control group (0.9%). In multivariable analysis, the odds ratio for haematological malignancy in offspring with maternal autoimmune diseases was 1.2 (95% confidence interval [CI] 0.91-1.58). The overall risk of haematologic malignancy was not significantly higher when adjusted for specific risk factors, including neonatal age, maternal age, family income, urbanization, maternal occupation, birth weight, or maternal comorbidity, except for prematurity. When comparing different autoimmune diseases among haematological malignancies and the control group, maternal psoriatic arthritis/psoriasis had the highest adjusted overall risk for haematological malignancies (adjusted OR 2.11, CI 0.89-5), followed by ankylosing spondylitis (adjusted OR 1.45, CI 0.7-3), autoimmune thyroiditis (OR 1.26, CI 0.57-2.81), systemic lupus erythematosus (OR 1.21, CI 0.48-3.02), Crohn's disease (OR 1.19, CI 0.75-1.9), and Sjogren's syndrome (OR 1.18, CI 0.65-2.15), but no significance was reached in these analyses. Multivariable analysis of risk factors associated with haematological malignancy subtypes was done. It showed no associations between maternal autoimmune disease and childhood haematological malignancies.

Interpretation

We found no significant relationship between maternal autoimmune disease and childhood haematological malignancies. The influence of maternal immune dysregulation on the next generation with respect to haematological malignancies development may be limited.

Funding

There was no funding source for this study.

Racial and ethnic and socioeconomic disparities in childhood cancer incidence trends in the United States, 2000-2019

BACKGROUND

Population-based surveillance of pediatric cancer incidence trends is critical to determine high-risk populations, drive hypothesis generation, and uncover etiologic heterogeneity. We provide a comprehensive update to the current understanding of pediatric cancer incidence trends by sex, race and ethnicity, and socioeconomic status (SES).

METHODS

The Surveillance, Epidemiology, and End Results 22 data (2000-2019) was used to summarize age-adjusted incidence rates for children and adolescents aged 0-19 years at diagnosis. The annual percentage change (APC) and 95% confidence interval (CI) were estimated to evaluate incidence trends by sex, race and ethnicity, and SES overall and for cancer subtypes. Tests of statistical significance were 2-sided.

RESULTS

Substantial variation was observed overall and for several histologic types in race and ethnicity- and SES-specific rates. Overall, we observed a statistically significant increase in incidence rates (APC = 0.8%, 95% CI = 0.6% to 1.1%). All race and ethnic groups saw an increase in incidence rates, with the largest occurring among non-Hispanic American Indian and Alaska Native children and adolescents (APC = 1.7%, 95% CI = 0.5% to 2.8%) and the smallest increase occurring among non-Hispanic White children and adolescents (APC = 0.7%, 95% CI = 0.5% to 1.0%). The lowest SES quintiles saw statistically significant increasing trends, while the highest quintile remained relatively stable (quintile 1 [Q1] APC = 1.6%, 95% CI = 0.6% to 2.6%; quintile 5 [Q5] APC = 0.3%, 95% CI = -0.1% to 0.7%).

CONCLUSIONS

Childhood cancer incidence is increasing overall and among every race and ethnic group. Variation by race and ethnicity and SES may enable hypothesis generation on drivers of disparities observed.

Unconventional Oil and Gas Development Exposure and Risk of Childhood Acute Lymphoblastic Leukemia: A Case-Control Study in Pennsylvania, 2009-2017

BACKGROUND

Unconventional oil and gas development (UOGD) releases chemicals that have been linked to cancer and childhood leukemia. Studies of UOGD exposure and childhood leukemia are extremely limited.

OBJECTIVE

The objective of this study was to evaluate potential associations between residential proximity to UOGD and risk of acute lymphoblastic leukemia (ALL), the most common form of childhood leukemia, in a large regional sample using UOGD-specific metrics, including a novel metric to represent the water pathway.

METHODS

We conducted a registry-based case-control study of 405 children ages 2-7 y diagnosed with ALL in Pennsylvania between 2009-2017, and 2,080 controls matched on birth year. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between residential proximity to UOGD (including a new water pathway-specific proximity metric) and ALL in two exposure windows: a primary window (3 months preconception to 1 y prior to diagnosis/reference date) and a perinatal window (preconception to birth).

RESULTS

Children with at least one UOG well within 2 km of their birth residence during the primary window had 1.98 times the odds of developing ALL in comparison with those with no UOG wells [95% confidence interval (CI): 1.06, 3.69]. Children with at least one vs. no UOG wells within 2 km during the perinatal window had 2.80 times the odds of developing ALL (95% CI: 1.11, 7.05). These relationships were slightly attenuated after adjusting for maternal race and socio-economic status [odds ratio (OR) = 1.74 (95% CI: 0.93, 3.27) and OR = 2.35 (95% CI: 0.93, 5.95)], respectively). The ORs produced by models using the water pathway-specific metric were similar in magnitude to the aggregate metric.

DISCUSSION

Our study including a novel UOGD metric found UOGD to be a risk factor for childhood ALL. This work adds to mounting evidence of UOGD's impacts on children's health, providing additional support for limiting UOGD near residences. https://doi.org/10.1289/EHP11092.

Cancer risks among studies of medical diagnostic radiation exposure in early life without quantitative estimates of dose

BACKGROUND

There is accumulating evidence of excess risk of cancer in various populations exposed at acute doses below several tens of mSv or doses received over a protracted period. There is also evidence that relative risks are generally higher after radiation exposures in utero or in childhood.

METHODS AND FINDINGS

We reviewed and summarised evidence from 89 studies of cancer following medical diagnostic exposure in utero or in childhood, in which no direct estimates of radiation dose are available. In all of the populations studied exposure was to sparsely ionizing radiation (X-rays). Several of the early studies of in utero exposure exhibit modest but statistically significant excess risks of several types of childhood cancer. There is a highly significant (p < 0.0005) negative trend of odds ratio with calendar period of study, so that more recent studies tend to exhibit reduced excess risk. There is no significant inter-study heterogeneity (p > 0.3). In relation to postnatal exposure there are significant excess risks of leukaemia, brain and solid cancers, with indications of variations in risk by cancer type (p = 0.07) and type of exposure (p = 0.02), with fluoroscopy and computed tomography scans associated with the highest excess risk. However, there is highly significant inter-study heterogeneity (p < 0.01) for all cancer endpoints and all but one type of exposure, although no significant risk trend with calendar period of study.

CONCLUSIONS

Overall, this large body of data relating to medical diagnostic radiation exposure in utero provides support for an associated excess risk of childhood cancer. However, the pronounced heterogeneity in studies of postnatal diagnostic exposure, the implied uncertainty as to the meaning of summary measures, and the distinct possibilities of bias, substantially reduce the strength of the evidence from the associations we observe between radiation imaging in childhood and the subsequent risk of cancer being causally related to radiation exposure.

Global, regional, and national cancer incidence and death for 29 cancer groups in 2019 and trends analysis of the global cancer burden, 1990-2019

Background and aims

Cancer will soon become the leading cause of death in every country in the twenty-first century. This study aimed to analyze the mortality and morbidity of 29 types of cancer in 204 countries or regions from 1990 to 2019 to guide global cancer prevention and control.

Methods

Detailed information for 29 cancer groups was collected from the Global Burden of Disease Study in 2019. The age-standardized incidence rate (ASIR) and age-standardized death rate (ASDR) of the 29 cancer groups were calculated based on sex, age, region, and country. In addition, separate analyses were performed for major cancer types.

Results

In 2019, more than 10 million people died from cancer, which was approximately twice the number in 1990. Tracheal, bronchus, and lung (TBL) cancers collectively showed the highest death rate, and the ASDR of pancreatic cancer increased by 24%, which was cancer with the highest case fatality rate (CFR). The global cancer ASIR showed an increasing trend, with testicular cancer, thyroid cancer, and malignant skin melanoma showing a significant increase. The ASDR and ASIR of cancer in males were about 1.5 times higher than that in females. Individuals over 50 years had the highest risk of developing cancer, with incidences and deaths in this age group accounting for more than 85% of cancers in all age groups. Asia has the heaviest cancer burden due to its high population density, with esophageal cancer in this region accounting for 53% of the total fatalities related to this type of cancer in the world. In addition, the mortality and morbidity of most cancers increased with the increase in the development or socio-demographic index (SDI) in the SDI regions based on the World Bank's Human Development Index (HDI), with cancer characteristics varying in the different countries globally.

Conclusions

The global cancer burden continues to increase, with substantial mortality and morbidity differences among the different regions, ages, countries, gender, and cancer types. Effective and locally tailored cancer prevention and control measures are essential in reducing the global cancer burden in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-021-01213-z.

Maternal Medication Use and Childhood Cancer in Offspring-Systematic Review and Considerations for Researchers

Cancer is an important cause of childhood mortality, yet the etiology is largely unknown. A combination of pre- and postnatal factors is thought to be implicated, including maternal medication use. We aimed to provide: 1) a systematic review of peer-reviewed publications on associations between maternal medication use and childhood cancer, with a focus on study design and methodology; and 2) suggestions for how to increase transparency, limit potential biases, and improve comparability in studies on maternal medication use and childhood cancer. We conducted a systematic search in the PubMed, Embase, Scopus, Cochrane, and Web of Science databases to June 8, 2020. Altogether, 112 studies were identified. The reviewed studies were heterogeneous in study design, exposure, and outcome classification. In 21 studies (19%), the outcome was any childhood cancer. Of the 91 papers that reported on specific types of cancer, 62% did not report the cancer classification system. The most frequently investigated medication groups were sex hormones (46 studies, excluding fertility medications), and antiinfectives (37 studies). Suggestions for strengthening future pharmacoepidemiologic studies on maternal medication use and childhood cancer relate to choice of cancer classification system, exposure windows, and methods for identification of, and control for, potential confounders.

A review of the types of childhood cancer associated with a medical X-ray examination of the pregnant mother

PURPOSE

For 65 years the interpretation of the statistical association between the risk of cancer in a child and a prior diagnostic X-ray examination of the abdomen of the pregnant mother has been debated. The objections to a direct cause-and-effect explanation of the association vary in their strength, but one of the most notable grounds for controversy is the finding from the first and largest case-control study reporting the association, the Oxford Survey of Childhood Cancers (OSCC), of an almost uniformly raised relative risk (RR) for nearly all of the types of cancer that are most frequent in children. Here we compare the antenatal X-ray associations found in the OSCC for different types of childhood cancer with the results of all other case-control and case-cohort studies appropriately combined in meta-analyses, and we also review the findings of the few cohort studies that have been conducted.

CONCLUSIONS

From the case-control/case-cohort studies other than the OSCC there are consistent and clear elevations of risk for all types of childhood cancer combined, all leukemia, and all cancers except leukemia combined. This compatibility of the findings of the OSCC with those of the combined other studies is less clear, or effectively absent, when some categories containing smaller numbers of incident cases/deaths are considered, but lack of precision of risk estimates due to sparse data presents inferential challenges, although there is a consistent absence of an association for bone tumors. Further, more recent studies almost certainly address lower intrauterine doses, with an anticipated decrease in estimated risks, which could be misleading when comparisons involve a limited number of studies that are mainly from later years, and a similar problem arises when having to employ all types of antenatal X-ray exposures for a study because data for abdominal exposures are absent. The problem of low statistical power is greater for cohort studies, and this, together with other shortcomings identified in the studies, limits the interpretational value of results. The findings of non-medical intrauterine exposure studies are constrained by sparse data and make a limited contribution to an understanding of the association. Certain aspects of the various studies require a need for caution in interpretation, but overall, the appropriate combination of all case-control/case-cohort studies other than the OSCC lends support to the inference that low-level exposure to radiation in utero proportionally increases the risk of the typical cancers of childhood to around the same level.

Caesarean sections, prenatal and postnatal conditions and childhood acute lymphoblastic leukaemia: A case-control study in the State of São Paulo, Brazil

INTRODUCTION

Brazil has high rates of caesarean sections, which has been suggested as a risk factor for acute lymphoblastic leukaemia (ALL). In addition, some pre- and postnatal conditions have been identified as relevant in the etiology of ALL.

OBJECTIVES

Investigate the association of caesarean sections, pre- and postnatal conditions with childhood ALL in the State of São Paulo.

METHODS

Population-based case-control study including children that are below10 years old. Information on study variables was obtained through face to face interviews, through a questionnaire, and the State of São Paulo Declarations of Live Births database. The conditional and unconditional logistic regression approaches were used to calculate the odds ratio (OR) of the associations between caesarean sections, pre- and postnatal conditions with ALL, and 95 % confidence intervals (95 % CI).

RESULTS

We observed a weak and non-statistically significant risk for ALL among children exposed to caesarean sections (unconditional logistic regression OR 1.08; 95 % CI 0.70-1.66; conditional logistic regression OR 1.21; 95 % CI 0.72-2.02), but among children under 3 years old and born through a caesarean sections, the risk of ALL was greater (unconditional logistic regression OR 1.70; 95 % CI 0.69-4.21). A negative association for ALL was observed among children with mothers who reported 12 years of schooling or more (unconditional logistic regression OR 0.34; 95 % CI 0.16-0.69).

CONCLUSIONS

We found a tenuous suggestive association between caesarean sections and childhood ALL. The mother's high level of education showed an inverse association with ALL.

Maternal Infection in Pregnancy and Childhood Leukemia: A Systematic Review and Meta-analysis

OBJECTIVE

To summarize the published evidence regarding the association between maternal infection during pregnancy and childhood leukemia.

STUDY DESIGN

In this systematic review and meta-analysis (PROSPERO number, CRD42018087289), we searched PubMed and Embase to identify relevant studies. We included human studies that reported associations of at least one measure of maternal infection during pregnancy with acute lymphoblastic leukemia (ALL) or all childhood leukemias in the offspring. One reviewer extracted the data first using a standardized form, and the second reviewer independently checked the data for accuracy. Two reviewers used the Newcastle-Ottawa Scale to assess the quality of included studies. We conducted random effects meta-analyses to pool the ORs of specific type of infection on ALL and childhood leukemia.

RESULTS

This review included 20 studies (ALL, n = 15; childhood leukemia, n = 14) reported in 32 articles. Most (>65%) included studies reported a positive association between infection variables and ALL or childhood leukemia. Among specific types of infection, we found that influenza during pregnancy was associated with higher risk of ALL (pooled OR, 3.64; 95% CI, 1.34-9.90) and childhood leukemia (pooled OR, 1.77; 95% CI, 1.01-3.11). Varicella (pooled OR, 10.19; 95% CI, 1.98-52.39) and rubella (pooled OR, 2.79; 95% CI, 1.16-6.71) infections were also associated with higher childhood leukemia risk.

CONCLUSIONS

Our findings suggest that maternal infection during pregnancy may be associated with a higher risk of childhood leukemia.

Exposure of Larval Zebrafish to the Insecticide Propoxur Induced Developmental Delays that Correlate with Behavioral Abnormalities and Altered Expression of hspb9 and hspb11

Recent studies suggest that organophosphates and carbamates affect human fetal development, resulting in neurological and growth impairment. However, these studies are conflicting and the extent of adverse effects due to pesticide exposure warrants further investigation. In the present study, we examined the impact of the carbamate insecticide propoxur on zebrafish development. We found that propoxur exposure delays embryonic development, resulting in three distinct developmental stages: no delay, mild delay, or severe delay. Interestingly, the delayed embryos all physically recovered 5 days after exposure, but behavioral analysis revealed persistent cognitive deficits at later stages. Microarray analysis identified 59 genes significantly changed by propoxur treatment, and Ingenuity Pathway Analysis revealed that these genes are involved in cancer, organismal abnormalities, neurological disease, and hematological system development. We further examined hspb9 and hspb11 due to their potential roles in zebrafish development and found that propoxur increases expression of these small heat shock proteins in all of the exposed animals. However, we discovered that less significant increases were associated with the more severely delayed phenotype. This raises the possibility that a decreased ability to upregulate these small heat shock proteins in response to propoxur exposure may cause embryos to be more severely delayed.

Pesticide exposure and cancer: an integrative literature review

ABSTRACT We conducted an integrative literature review of published studies on pesticide and cancer exposure, focusing on farmers, rural population, pesticide applicators, and rural workers. The Medline/PubMed was used as searching database. After the retrieval, 74 articles were selected according to pre-established criteria, which design involved 39 case-controls, 32 cohorts, 2 ecological ones, and 1 cross-sectional. Among them, 64 studies showed associations between pesticides and cancer while 10 did not find any significant association. The studies found 53 different types of pesticides significantly associated with at least one type of cancer and 19 different types of cancers linked to at least one type of pesticide. Although few studies presented contradictory results, the sole fact of being a farmer or living near crops or high agricultural areas have also been used as a proxy for pesticide exposure and significantly associated with higher cancer risk. The literature well illustrates the case of prostate cancer, Non-Hodgkin lymphoma, leukemia, multiple myeloma, bladder and colon cancers. Studies are recommended to further investigate the relationship between pesticide and neoplasm of testis, breast, esophagus, kidney, thyroid, lip, head and neck, and bone.

DNA damage signalling from the placenta to foetal blood as a potential mechanism for childhood leukaemia initiation

For many diseases with a foetal origin, the cause for the disease initiation remains unknown. Common childhood acute leukaemia is thought to be caused by two hits, the first in utero and the second in childhood in response to infection. The mechanism for the initial DNA damaging event are unknown. Here we have used in vitro, ex vivo and in vivo models to show that a placental barrier will respond to agents that are suspected of initiating childhood leukaemia by releasing factors that cause DNA damage in cord blood and bone marrow cells, including stem cells. We show that DNA damage caused by in utero exposure can reappear postnatally after an immune challenge. Furthermore, both foetal and postnatal DNA damage are prevented by prenatal exposure of the placenta to a mitochondrially-targeted antioxidant. We conclude that the placenta might contribute to the first hit towards leukaemia initiation by bystander-like signalling to foetal haematopoietic cells.

Maternal prenatal exposure to environmental factors and risk of childhood acute lymphocytic leukemia: A hospital-based case-control study in China

OBJECTIVE

To investigate an association between maternal prenatal exposure to several environmental factors and risk of childhood acute lymphocytic leukemia (ALL), and the possible interactions in the Chinese population.

METHODS

345 cases with ALL and their 1:1 age, gender, residence region matched controls aged 0-15 years were recruited from four hospitals in Henan Province from 2014 to 2016. Information was collected by interviews using a questionnaire. Unconditional logistic regression adjusted for age, gender, residence region and relevant confounders was carried out to generate the odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Our data indicate that maternal prenatal exposure to interior housing renovation (adjusted OR: 2.98, 95% CI: 1.51-5.86) or pesticides (adjusted OR: 1.48, 95% CI: 1.67-2.28) increased the risk of childhood ALL. Various subgroup analyses stratified by child's gender, age at diagnosis and other factors also supported these results. However, no interaction was detected between exposure to internal housing renovation and pesticides using an additive model. No significant links between maternal exposures to, environmental tobacco smoking (ETS), antipyretic analgesia intake, or viral infectious diseases with risk of ALL were detected.

CONCLUSION

Findings in our study are in line with the existing literatures, which support the hypothesis that maternal prenatal exposure to interior housing renovation and pesticides are risk factors for childhood ALL. Notably, we found no interaction between these two risk factors, these findings may inform prevention and early detection strategies.

Protective effect of breastfeeding against childhood leukemia in Zhejiang Province, P. R. China: a retrospective case-control study

OBJECTIVES

Our research investigated the relationship between childhood leukemia and breastfeeding in the P. R. of China.

METHODS

We conducted a retrospective case-control study from March 2008 to April 2017 at the Children's Hospital of Zhejiang University, Zhejiang province, P. R. of China, which reviewed 958 children who had been diagnosed with leukemia in case group and 785 healthy children in control group. Data were obtained from medical records, and if the medical records were incomplete, we called mothers of children by phone to complete the data.

RESULTS

Breastfeeding reduces the risk of childhood leukemia; the effect is greater, if feeding continued for 7-9 months (p = 0.002). In addition, we suggest that some factors such as maternal age, smoking during pregnancy, abortion history, genetic factors, parents use of hair dye, and the history of using birth control pills before pregnancy can increase the risk of childhood leukemia.

CONCLUSIONS

This study indicates that promoting breastfeeding for 7-9 months may help lower the childhood leukemia incidence. Our study firstly demonstrates that breastfeeding has protective effects against childhood leukemia in the P. R. of China.

ABBREVIATIONS

ALL: Acute lymphocytic leukemia; AML: Acute myeloid leukemia.

Hazardous effects of chemical pesticides on human health-Cancer and other associated disorders

Poisoning from pesticides is a global public health problem and accounts for nearly 300,000 deaths worldwide every year. Exposure to pesticides is inevitable; there are different modes through which humans get exposed to pesticides. The mode of exposure is an important factor as it also signifies the concentration of pesticides exposure. Pesticides are used extensively in agricultural and domestic settings. These chemicals are believed to cause many disorders in humans and wildlife. Research from past few decades has tried to answer the associated mechanism of action of pesticides in conjunction with their harmful effects. This perspective considers the past and present research in the field of pesticides and associated disorders. We have reviewed the most common diseases including cancer which are associated with pesticides. Pesticides have shown to be involved in the pathogenesis of Parkinson's and Alzheimer's diseases as well as various disorders of the respiratory and reproductive tracts. Oxidative stress caused by pesticides is an important mechanism through which many of the pesticides exert their harmful effects. Oxidative stress is known to cause DNA damage which in turn may cause malignancies and other disorders. Many pesticides have shown to modulate the gene expression at the level of non-coding RNAs, histone deacetylases, DNA methylation patterns suggesting their role in epigenetics.

Maternal Exposure to Pesticides, Paternal Occupation in the Army/Police Force, and CYP2D6*4 Polymorphism in the Etiology of Childhood Acute Leukemia

Epidemiologic studies have suggested that parental occupations, pesticide use, environmental factors, and genetic polymorphism are involved in the etiology of childhood acute leukemia (CAL). In total, 116 cases of CAL and 162 controls were recruited and submitted to blood drawing to assess the presence of genetic polymorphisms. Parental occupations, pesticides exposure, and other potential determinants were investigated. Increased risk for CAL was associated with prenatal maternal use of insecticides/rodenticides (odds ratio [OR]=1.87; 95% confidence intervals [CI], 1.04-3.33), with subjects living <100 m from pesticide-treated fields (OR=3.21; 95% CI, 1.37-7.53) and with a paternal occupation as traffic warden/policeman (OR=4.02; 95% CI, 1.63-9.87). Associations were found between CAL and genetic polymorphism of CYP2D6*4 for homozygous alleles (mutant type/mutant type: OR=6.39; 95% CI, 1.17-34.66). In conclusion, despite the small sample size, maternal prenatal exposure to pesticides, paternal occupation as a traffic warden/police officer, and CYP2D6*4 polymorphism could play a role in the etiology of CAL.

Parental Occupational Exposures and Risk of Childhood Acute Leukemia

Introduction:

Acute leukemia, accounting for 20% of all cancers diagnosed in individuals younger than 19 years old, is the most prevalent childhood malignancy. Among environmental risk factors, parental occupational exposures have attracted scientific interest as potential predisposing factors for childhood leukemia. The role of parental occupational exposure to social contacts, harmful chemicals, electromagnetic fields and ionizing radiation has been investigated with conflicting and inconsistent results.

Aim:

A case-control study aiming to assess the association between parental occupational exposures to social contacts, chemicals and electromagnetic fields and the risk of offspring acute leukemia.

Material and Methods:

108 children with acute leukemia and equal number of matched controls were included. Data on parental occupations before conception, during pregnancy, during breastfeeding and after birth, and on potential risk factors was recorded. Associations between parental exposure and risk of childhood leukemia were estimated.

Results:

Parental occupational exposure during the four periods of exposure was not associated with childhood leukemia. High birth weight and family history of cancer were associated with the development of childhood acute leukemia. A weak association of maternal medication use during pregnancy and leukemia risk emerged.

Conclusions:

Since the causative factors of childhood leukemia remain unknown, further investigation is mandatory for the reduction of disease burden.

Maternal fetal loss history and increased acute leukemia subtype risk in subsequent offspring: a systematic review and meta-analysis

PURPOSE

History of fetal loss including miscarriage and stillbirth has been inconsistently associated with childhood (0-14 years) leukemia in subsequent offspring. A quantitative synthesis of the inconclusive literature by leukemia subtype was therefore conducted.

METHODS

Eligible studies (N = 32) were identified through the screening of over 3500 publications. Random-effects meta-analyses were conducted on the association of miscarriage/stillbirth history with overall (AL; 18,868 cases/35,685 controls), acute lymphoblastic (ALL; 16,150 cases/38,655 controls), and myeloid (AML; 3042 cases/32,997 controls) leukemia. Sensitivity and subgroup analyses by age and ALL subtype, as well as meta-regression were undertaken.

RESULTS

Fetal loss history was associated with increased AL risk [Odds Ratio (OR) 1.10, 95% Confidence Intervals (CI) 1.04-1.18]. The positive association was seen for ALL (OR 1.12, 95%CI 1.05-1.19) and for AML (OR 1.13, 95%CI 0.91-1.41); for the latter the OR increased in sensitivity analyses. Notably, stillbirth history was significantly linked to ALL risk (OR 1.33, 95%CI 1.02-1.74), but not AML. By contrast, the association of ALL and AML with previous miscarriage reached marginal significance. The association of miscarriage history was strongest in infant ALL (OR 2.34, 95%CI 1.19-4.60).

CONCLUSIONS

In this meta-analysis involving >50,000 children, we found noteworthy associations by indices of fetal loss, age at diagnosis, and leukemia type; namely, of stillbirth with ALL and miscarriage history with infant ALL. Elucidation of plausible underlying mechanisms may provide insight into leukemia pathogenesis and indicate monitoring interventions prior to and during pregnancy.

Aberrant Expression of HOXA5 and HOXA9 in AML

BACKGROUND

Aberrant expression of HOX gene expression has been observed in cancer. The purpose of this study was to investigate the alteration of HOXA5 and HOXA9 expression and their clinical significance in acute meloid leukemia (AML).

MATERIALS AND METHODS

The expression of HOXA5 and HOXA9 genes of bone marrow samples from 75 newly diagnosed AML patients and 22 healthy controls for comparison were examined by Real- time quantitative PCR (RQ-PCR) assay. Statistical analysis was conducted to evaluate HOXA5 and HOXA9 expression as possible biomarkers for AML.

RESULTS

The results showed that the complete remission rate (52.6%) of the patients who highly expressed HOXA5 and HOXA9 was significantly lower than that (88.9%) in patients who lowly express the genes (P=0.015). Spearmann correlation coefficients indicated that the expression levels for HOXA5 and HOXA9 genes were highly interrelated (r=0.657, P<0.001). Meanwhile, we detected significant correlations between HOXA9 expression and age in this limited set of patients (P=0.009).

CONCLUSIONS

The results suggest a prognostic impact of increased expression of HOXA5 and HOXA9 in AML patients.