Maternal and infant birth characteristics and hepatoblastoma

Cancer risk among children born after assisted conception

BACKGROUND

Accurate population-based data are needed on the incidence of cancer in children born after assisted conception.

METHODS

We linked data on all children born in Britain between 1992 and 2008 after assisted conception without donor involvement with data from the United Kingdom National Registry of Childhood Tumours to determine the number of children in whom cancer developed before 15 years of age. Cohort cancer rates were compared with population-based rates in Britain over the same period, with stratification for potential mediating and moderating factors, including sex, age at diagnosis, birth weight, singleton versus multiple birth, parity, parental age, type of assisted conception, and cause of parental infertility.

RESULTS

The cohort consisted of 106,013 children born after assisted conception (700,705 person-years of observation). The average duration of follow-up was 6.6 years. Overall, 108 cancers were identified, as compared with 109.7 expected cancers (standardized incidence ratio, 0.98; 95% confidence interval [CI], 0.81 to 1.19; P=0.87). Assisted conception was not associated with an increased risk of leukemia, neuroblastoma, retinoblastoma, central nervous system tumors, or renal or germ-cell tumors. It was associated with an increased risk of hepatoblastoma (standardized incidence ratio, 3.64; 95% CI, 1.34 to 7.93; P=0.02; absolute excess risk, 6.21 cases per 1 million person-years) and rhabdomyosarcoma (standardized incidence ratio, 2.62; 95% CI, 1.26 to 4.82; P=0.02; absolute excess risk, 8.82 cases per 1 million person-years), with hepatoblastoma developing in 6 children and rhabdomyosarcoma in 10 children. The excess risk of hepatoblastoma was associated with low birth weight.

CONCLUSIONS

There was no increase in the overall risk of cancer among British children born after assisted conception during the 17-year study period. Increased risks of hepatoblastoma and rhabdomyosarcoma were detected, but the absolute risks were small. (Funded by Cancer Research UK and others.).

Maternal prenatal weight gain and autism spectrum disorders

BACKGROUND

The rising population of individuals identified with an autism spectrum disorder (ASD) calls for further investigation of its underlying etiology. A disturbance in the fetal steroid hormone environment may be a mechanism in which environmental and genetic risk factors interact. The mother, fetus, and placenta collectively create the fetal steroid environment. Prepregnancy BMI and pregnancy weight gain have served as markers for fetal steroid hormone exposure in other disease states. This study's objective is to determine whether prepregnancy BMI and pregnancy weight gain are associated with increased ASD risk across study designs and cohorts while controlling for important confounding variables.

METHODS

A population-based Utah ASD cohort (n = 128) was ascertained in a 3-county surveillance area and gender- and age-matched to 10,920 control subjects. A second, research-based ASD cohort of Utah children (n = 288) and their unaffected siblings (n = 493) were ascertained through participation in an ASD genetics study. Prenatal variables were obtained from birth certificate records.

RESULTS

ASD risk was significantly associated with pregnancy weight gain (adjusted odds ratio = 1.10, 95% confidence interval: 1.03 to 1.17; adjusted odds ratio = 1.17, 95% confidence interval: 1.01 to 1.35 for each 5 pounds of weight gained), but not prepregnancy BMI, in population and research-based cohorts, respectively. When analyses were restricted to ASD cases with normal IQ, these associations remained significant.

CONCLUSIONS

ASD risk associated with a modest yet consistent increase in pregnancy weight gain suggests that pregnancy weight gain may serve as an important marker for autism's underlying gestational etiology. This justifies an investigation into phenomena that link pregnancy weight gain and ASD independent of prepregnancy BMI.

Prenatal exposure to traffic-related air pollution and risk of early childhood cancers

Exposure to air pollution during pregnancy has been linked to the risk of childhood cancer, but the evidence remains inconclusive. In the present study, we used land use regression modeling to estimate prenatal exposures to traffic exhaust and evaluate the associations with cancer risk in very young children. Participants in the Air Pollution and Childhood Cancers Study who were 5 years of age or younger and diagnosed with cancer between 1988 and 2008 were had their records linked to California birth certificates, and controls were selected from birth certificates. Land use regression-based estimates of exposures to nitric oxide, nitrogen dioxide, and nitrogen oxides were assigned based on birthplace residence and temporally adjusted using routine monitoring station data to evaluate air pollution exposures during specific pregnancy periods. Logistic regression models were adjusted for maternal age, race/ethnicity, educational level, parity, insurance type, and Census-based socioeconomic status, as well as child's sex and birth year. The odds of acute lymphoblastic leukemia increased by 9%, 23%, and 8% for each 25-ppb increase in average nitric oxide, nitrogen dioxide, and nitrogen oxide levels, respectively, over the entire pregnancy. Second- and third-trimester exposures increased the odds of bilateral retinoblastoma. No associations were found for annual average exposures without temporal components or for any other cancer type. These results lend support to a link between prenatal exposure to traffic exhaust and the risk of acute lymphoblastic leukemia and bilateral retinoblastoma.

Parental tobacco and alcohol use and risk of hepatoblastoma in offspring: a report from the children's oncology group

BACKGROUND

Hepatoblastoma is a rare pediatric liver tumor that has significantly increased in incidence over the last several decades. The International Agency for Research on Cancer (IARC) recently classified hepatoblastoma as a tobacco-related cancer. Parental alcohol use has shown no association. We examined associations between parental tobacco and alcohol use around the time of pregnancy and hepatoblastoma in a large case-control study.

METHODS

Maternal interviews were completed for 383 cases diagnosed in the United States during 2000-2008. Controls (n = 387) were identified through U.S. birth registries and frequency-matched to cases on birth weight, birth year, and region of residence. We used unconditional logistic regression to calculate ORs and 95% confidence intervals (CI) for associations between parental smoking and maternal drinking and offspring hepatoblastoma.

RESULTS

We found no association between hepatoblastoma and maternal smoking at any time (OR, 1.0; 95% CI, 0.7-1.4), within the year before pregnancy (OR, 1.1; 95% CI, 0.8-1.6), early in pregnancy (OR, 1.0; 95% CI, 0.7-1.6), or throughout pregnancy (OR, 0.9; 95% CI, 0.5-1.6). We observed marginally positive associations between hepatoblastoma and paternal smoking in the year before pregnancy (OR, 1.4; 95% CI, 1.0-2.0) and during pregnancy (OR, 1.4; 95% CI, 0.9-2.0). Maternal alcohol use was not associated with hepatoblastoma.

CONCLUSION

Our results do not provide evidence for an etiologic relationship between maternal smoking or drinking and hepatoblastoma, and only weak evidence for an association for paternal smoking in the year before pregnancy.

IMPACT

Our study provides limited support for hepatoblastoma as a tobacco-related cancer; however, it remains wise to counsel prospective parents on the merits of smoking cessation.

The SPLIT research agenda 2013

This review focuses on active clinical research in pediatric liver transplantation with special emphasis on areas that could benefit from studies utilizing the SPLIT infrastructure and data repository. Ideas were solicited by members of the SPLIT Research Committee and sections were drafted by members of the committee with expertise in those given areas. This review is intended to highlight priorities for clinical research that could successfully be conducted through the SPLIT collaborative and would have significant impact in pediatric liver transplantation.

IVF and breast cancer: a systematic review and meta-analysis

BACKGROUND

The effects of controlled ovarian hyperstimulation (COH) for IVF in terms of breast cancer risk remain controversial, despite the hormone-dependent nature of the latter.

METHODS

Eligible studies up to 15 February 2013 were identified and pooled effect estimates for relative risk (RR) were calculated separately for the investigations using the general population and those using infertile women, as a reference group. Fixed- or random-effects models were implemented and subgroup analyses were performed, as appropriate.

RESULTS

Eight cohort studies were synthesized, yielding a total cohort size of 1,554,332 women among whom 14,961 incident breast cancer cases occurred, encompassing 576 incident breast cancer cases among women exposed to IVF. No significant association between IVF and breast cancer was observed either in the group of studies treating the general population (RR = 0.91, 95% confidence interval (CI): 0.74-1.11) or infertile women (RR = 1.02, 95% CI: 0.88-1.18), as a reference group. Of note were the marginal associations, protective for pregnant and/or parous women after IVF (pooled effect estimate = 0.86, 95% CI: 0.73-1.01) and adverse for women <30 years at first IVF treatment (pooled effect estimate = 1.64, 95% CI: 0.96-2.80).

CONCLUSIONS

At present, COH for IVF does not seem to impart increased breast cancer risk. Longer follow-up periods, comparisons versus infertile women, subgroup analyses aiming to trace vulnerable subgroups, adjustment for various confounders and larger informative data sets are needed before conclusive statements for the safety of the procedure are reached.

Maternal pregnancy events and exposures and risk of hepatoblastoma: a Children's Oncology Group (COG) study

BACKGROUND

Hepatoblastoma is a rare childhood liver cancer with an obscure etiology, however it is potentially associated with selected pregnancy events and hepatoblastoma risk in offspring.

METHODS

Adjusted unconditional logistic regression estimated odds ratios (OR) and corresponding 95% confidence intervals (CI) for self-reported pregnancy events and medication use in a sample of mothers of 383 childhood hepatoblastoma cases and 387 controls.

RESULTS

Risk of hepatoblastoma was significantly associated with maternal first trimester weight gain (OR = 1.02; 95% CI 1.00, 1.04 per 1 lb increase and nearly significantly with maternal multivitamin use (OR = 0.73; 95% CI 0.51, 1.03). Hepatoblastoma was not associated with other maternal weight changes, maternal illness or medication use during pregnancy.

CONCLUSION

We found little evidence that maternal illness or most medication use during pregnancy are associated with hepatoblastoma in offspring.

Long-term follow-up of children conceived through assisted reproductive technology

Children conceived via assisted reproductive technologies (ART) are nowadays a substantial proportion of the population. It is important to follow up these children and evaluate whether they have elevated health risks compared to naturally conceived (NC) children. In recent years there has been a lot of work in this field. This review will summarize what is known about the health of ART-conceived children, encompassing neonatal outcomes, birth defects, growth and gonadal developments, physical health, neurological and neurodevelopmental outcomes, psychosocial developments, risk for cancer, and epigenetic abnormalities. Most of the children conceived after ART are normal. However, there is increasing evidence that ART-conceived children are at higher risk of poor perinatal outcome, birth defects, and epigenetic disorders, and the mechanism(s) leading to these changes have not been elucidated. Continuous follow-up of children after ART is of great importance as they progress through adolescence into adulthood, and new ART techniques are constantly being introduced.

Fertility treatment and childhood cancer risk: a systematic meta-analysis

OBJECTIVE

To clarify the association between fertility treatment and the risk for cancer in children.

DESIGN

Meta-analysis.

SETTING

None.

PATIENT(S)

Twenty-five cohort and case-control studies involving children born after fertility treatment as the exposure of interest and cancer as the outcome.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Medline was searched through September 2012 to identify relevant studies. The study-specific estimates for each cancer outcome were combined into a pooled relative risk (RR) with 95% confidence interval (CI) by a meta-analytic approach.

RESULT(S)

We found that children born after fertility treatment were at increased risk for all cancers (RR = 1.33; 95% CI, 1.08-1.63) and for hematological cancers (RR = 1.59; 95% CI, 1.32-1.91), central nervous system/neural cancers (RR = 1.88; 95% CI, 1.02-3.46), and other solid cancers (RR = 2.19; 95% CI, 1.26-3.80). For specific cancer types, we found increased risks for leukemias (RR = 1.65; 95% CI, 1.35-2.01), neuroblastomas (RR = 4.04; 95% CI, 1.24-13.18), and retinoblastomas (RR = 1.62; 95% CI, 1.12-2.35) associated with fertility treatment.

CONCLUSION(S)

The results of the largest meta-analysis on this topic to date indicate an association between fertility treatment and cancer in offspring. However, our results do not rule out that factors related to underlying subfertility, rather than the procedure itself, are the most important predisposing factors for childhood cancer.

ART and health: clinical outcomes and insights on molecular mechanisms from rodent studies

Since the birth of the first IVF-conceived child in 1978, the use of assisted reproductive technologies (ART) has grown dramatically, contributing to the successful birth of 5 million individuals worldwide. However, there are several reported associations of ART with pregnancy complications, such as low birthweight (LBW), preterm birth, birth defects, epigenetic disorders, cancer and poor metabolic health. Whether this is attributed to ART procedures or to the subset of the population seeking ART remains a controversy, but the most relevant question today concerns the potential long-term implications of assisted conception. Recent evidence has emerged suggesting that ART-conceived children have distinct metabolic profiles that may predispose to cardiovascular pathologies in adulthood. Because the eldest IVF individuals are still too young to exhibit components of chronic middle-aged syndromes, the use of animal models has become particularly useful in describing the effects of unusual or stressful preimplantation experiences on adult fitness. Elucidating the molecular mechanisms by which embryos integrate environmental signals into development and metabolic gene expression programs will be essential for optimizing ART procedures such as in vitro culture conditions, embryo selection and transfer. In the future, additional animal studies to identify mechanisms underlying unfavorable ART outcomes, as well as more epidemiological reviews to monitor the long-term health of ART children are required, given that ART procedures have become routine medical practice.

Case-control study of birth characteristics and the risk of hepatoblastoma

BACKGROUND

Hepatoblastoma is a malignant embryonal tumor typically diagnosed in children younger than five years of age. Little is known on hepatoblastoma etiology.

METHODS

We matched California Cancer Registry records of hepatoblastomas diagnosed in children younger than age 6 from 1988 to 2007 to birth records using a probabilistic record linkage program, yielding 261 cases. Controls (n=218,277), frequency matched by birth year to all cancer cases in California for the same time period, were randomly selected from California birth records. We examined demographic and socioeconomic information, birth characteristics, pregnancy history, complications in pregnancy, labor and delivery, and abnormal conditions and clinical procedures relating to the newborn, with study data taken from birth certificates.

RESULTS

We observed increased risks for hepatoblastoma among children with low [1500-2499 g, Odds Ratio (OR)=2.02, 95% confidence interval (CI) 1.29-3.15] and very low birthweight (<1500 g, OR=15.4, 95% CI 10.7-22.3), preterm birth <33 weeks (OR=7.27, 95% CI 5.00, 10.6), small size for gestational age (OR=1.75, 95% CI 1.25-2.45), and with multiple birth pregnancies (OR=2.52, 95% CI 1.54-4.14). We observed a number of pregnancy and labor complications to be related to hepatoblastoma, including preeclampsia, premature labor, fetal distress, and congenital anomalies.

CONCLUSION

These findings confirm previously reported associations with low birthweight and preeclampsia. The relation with multiple birth pregnancies has been previously reported and may indicate a relation to infertility treatments.

Increased risk for cancer among offspring of women with fertility problems

Some studies have indicated that children born after fertility treatment have a potential risk for cancer, but the results are inconsistent. Furthermore, any negative effects of fertility treatment might be due to the underlying infertility rather than to the procedure itself. In the largest cohort study to date with information on fertility, we examined whether the offspring of women with fertility problems had a higher risk for cancer than offspring of women without fertility problems. The study cohort consisted of 2,830,054 offspring born in Denmark between 1964 and 2006. Of these, 125,844 were offspring of women evaluated for infertility. Cox regression models were used to estimate the possible effect of being the offspring of a woman evaluated for infertility on the risk for cancer. Analyses were performed separately for cancer during childhood (0-19 years) and cancer in young adulthood (>20 years). We found that offspring born to women with fertility problems had higher overall risks for cancer in childhood (hazard ratio (HR), 1.18; 95% confidence interval (CI), 1.05-1.32) and in young adulthood (HR, 1.22; 95% CI, 1.04-1.43) than offspring of women without fertility problems. Offspring of women with fertility problems had significantly increased risks for leukemia in childhood (HR, 1.30; 95% CI, 1.06-1.60) and for cancer of the endocrine glands in young adulthood (HR, 2.67; 95% CI, 1.35-5.29). These findings suggest that offspring born to mothers with fertility problems are at increased risk for cancer in both childhood and young adulthood. If real, our findings of an ∼18% overall increase in risk for cancer in childhood and an ∼22% overall increase in risk for cancer in young adulthood would mean about four additional cases of childhood cancer and about nine additional cases of cancer in young adults per 100,000 exposed offspring.

Preimplantation stress and development

The developmental origins of health and disease hypothesis holds that inappropriate environmental cues in utero, a period marked by tremendous developmental sensitivity, facilitate cellular reprogramming to ultimately predispose disease in adulthood. In this review, we analyze if stress during early stages of development can affect future health. This has wide clinical importance, given that 5 million children have been conceived with assisted reproductive technologies (ART). Because the primary outcome of assisted reproduction procedures is delivery at term of a live, healthy baby, the postnatal effects occurring outside ofthe neonatal period are often overlooked. To this end, the long-term outcome of ART is appropriately the most relevant concern of the field today. Evidence of adverse consequences is controversial. The majority of studies have concluded no obvious problems in IVF-conceived children, although a number of isolated cases of imprinted diseases, cancers, or malformations have been reported. Given that animal studies suggest alteration of metabolic pathways following preimplantation stress, it will be of great importance to follow-up ART individuals as they enter later stages of adult life.

The epidemiology of hepatoblastoma

Few causes of hepatoblastoma have been conclusively identified, mainly due to the extreme rarity of the disease. Inherited conditions including Familial Adenomatous Polyposis and Beckwith-Wiedemann Syndrome dramatically raise risk of hepatoblastoma but account for few cases overall. A small number of case-control studies investigating risk factors for sporadic hepatoblastoma have been conducted to date. Although most of these studies feature fewer than 200 cases, several clues have emerged. Most notably there is a roughly 20-fold increased risk of hepatoblastoma among children with very low birth weight (<1,500 g) and a doubling of risk among those with moderately low birth weight (1,500-2,500 g). A modicum of evidence points to a possible role of parental tobacco use prior to or during pregnancy in the causation of hepatoblastoma as well.

Current concepts in pediatric liver tumors

Liver tumors in children can be classified into benign or malignant; some of the benign lesions can have the potential of malignant transformation, and therefore the therapeutic approach may change. These neoplasms account for nearly 1-2% of all pediatric tumors and they have gained significant attention in the last decades due to data suggesting that the incidence may be increasing 5% annually. We know that with new and improved imaging modalities some of these lesions may be detected more often than before. Recent studies showed that liver cancer represented 2% of malignancies in infants by 1980s and this was doubled in incidence to 4% in the following 10 yr. In this review our aim is to discuss all primary liver tumors in children with attention to their clinicopathological and immunohistochemical features followed by the current standard of care.

The epigenetic effects of a high prenatal folate intake in male mouse fetuses exposed in utero to arsenic

Inorganic arsenic (iAs) is a complete transplacental carcinogen in mice. Previous studies have demonstrated that in utero exposure to iAs promotes cancer in adult mouse offspring, possibly acting through epigenetic mechanisms. Humans and rodents enzymatically convert iAs to its methylated metabolites. This reaction requires S-adenosylmethionine (SAM) as methyl group donor. SAM is also required for DNA methylation. Supplementation with folate, a major dietary source of methyl groups for SAM synthesis, has been shown to modify iAs metabolism and the adverse effects of iAs exposure. However, effects of gestational folate supplementation on iAs metabolism and fetal DNA methylation have never been thoroughly examined. In the present study, pregnant CD1 mice were fed control (i.e. normal folate, or 2.2 mg/kg) or high folate diet (11 mg/kg) from gestational day (GD) 5 to 18 and drank water with 0 or 85 ppm of As (as arsenite) from GD8 to 18. The exposure to iAs significantly decreased body weight of GD18 fetuses and increased both SAM and S-adenosylhomocysteine (SAH) concentrations in fetal livers. High folate intake lowered the burden of total arsenic in maternal livers but did not prevent the effects of iAs exposure on fetal weight or hepatic SAM and SAH concentrations. In fact, combined folate-iAs exposure caused further significant body weight reduction. Notably, iAs exposure alone had little effect on DNA methylation in fetal livers. In contrast, the combined folate-iAs exposure changed the CpG island methylation in 2,931 genes, including genes known to be imprinted. Most of these genes were associated with neurodevelopment, cancer, cell cycle, and signaling networks. The canonical Wnt-signaling pathway, which regulates fetal development, was among the most affected biological pathways. Taken together, our results suggest that a combined in utero exposure to iAs and a high folate intake may adversely influence DNA methylation profiles and weight of fetuses, compromising fetal development and possibly increasing the risk for early-onset of disease in offspring.

Renal and hepatic tumors in the neonatal period

Renal and hepatic tumors in neonates are extremely rare. Nevertheless it is important for clinicians to be familiar with them. Both renal and hepatic neonatal tumors are heterogeneous collections of several tumor types. Some renal and hepatic tumors are benign and may require no interventions whereas others can be associated with significant morbidity and even mortality and may require multimodality treatment. Early diagnosis and initiation of the proper treatment plan is crucial for achieving the best outcomes for these rare tumors in this vulnerable population.

Antenatal maternal bereavement and childhood cancer in the offspring: a population-based cohort study in 6 million children

Background:

Prenatal stress may increase the susceptibility to childhood cancer by affecting immune responses and hormonal balance. We examined whether antenatal stress following maternal bereavement increased the risk of childhood cancer.

Methods:

All children born in Denmark from 1968 to 2007 (N=2 743 560) and in Sweden from 1973 to 2006 (N=3 400 212) were included in this study. We compared cancer risks in children born to women who lost a first-degree relative (a child, spouse, a parent, or a sibling) the year before pregnancy or during pregnancy with cancer risks in children of women who did not experience such bereavement.

Results:

A total of 9795 childhood cancer cases were observed during follow-up of 68 360 707 person years. Children born to women who lost a child or a spouse, but not those who lost other relatives, had an average 30% increased risk of any cancer (hazard ratio (HR) 1.30, 95% confidence interval (CI) 0.96–1.77). The HRs were the highest for non-Hodgkin disease (512 cases in total, HR 3.40, 95% CI 1.51–7.65), hepatic cancer (125 cases in total, HR 5.51, 95% CI 1.34–22.64), and testicular cancer (86 cases in total, HR 8.52, 95% CI 2.03–37.73).

Conclusion:

Our data suggest that severe antenatal stress following maternal bereavement, especially due to loss of a child or a spouse, is associated with an increased risk of certain childhood cancers in the offspring, such as hepatic cancer and non-Hodgkin disease, but not with childhood cancer in general.

Primary malignant liver tumors in children

Liver tumors constitute only 1-4% of all solid tumors in children. Two-thirds of these are malignant. The primary malignant tumors are hepatoblastoma (HB), hepatocellular carcinoma (HCC), rhabdomyosarcoma (RMS), angiosarcoma, rhabdoid tumor, undifferentiated sarcoma and other rarer tumors. Of these HB is the commonest. The diagnosis of HB is based on the radiology, elevated levels of α-fetoprotein (αFP) and the histology/cytology. Staging is essential for risk categorization, risk adapted treatment and prognostication. The commonest staging and risk categorization system used today is PRETEXT system that is being used by nearly all multicentre trials (American, European, German, Japanese) in some way. Treatment of HB is multimodal with surgery and chemotherapy being the main modalities. Survival is not possible without complete surgical resection. Majority of tumors are unresectable at presentation but can be made resectable with chemotherapy, giving a resection rate of more than 85%. Cisplatin is the main stay of chemotherapy and is a part of all multidrug protocols. The 3-y overall survival (OS) today stands at 62%-70% but only 25% patients with metastasis get cured. Panhepatic tumors and those with local factors causing unresectability are now dealt with liver transplantation which has also given a survival rate of nearly 85%. The overall management of HB and HCC has evolved over the past 3 decades giving good long term survival rates for HB, though patients with HCC still do poorly. Successive therapeutic trials have focused attention on increasing the efficiency and reducing the toxicity and long term side effects of the treatment. Among the other uncommon tumors the rhabdoid tumor and angiosarcoma are chemoresistant and have a poor outcome while the undifferentiated sarcoma and rhabdomyosarcoma are now showing better response to the currently used chemotherapy combinations.

In vitro fertilization and risk of childhood leukemia in Greece and Sweden

BACKGROUND

Cancer risk in children born after in vitro fertilization (IVF) remains largely unknown. We aimed to investigate risk of leukemia and lymphoma following IVF using two nationwide datasets.

METHODS

The hospital-based case-control study in Greece derived from the National Registry for Childhood Hematological Malignancies (1996-2008, 814 leukemia and 277 lymphoma incident cases with their 1:1 matched controls). The Swedish case-control study was nested in the Swedish Medical Birth Register (MBR) (1995-2007, 520 leukemia and 71 lymphoma cases with their 5,200 and 710 matched controls) with ascertainment of incident cancer cases in the National Cancer Register. Study-specific and combined odds ratios (OR) were estimated using conditional logistic regression, with adjustment for possible risk factors.

RESULTS

Nationwide studies pointed to similar size excess risk of leukemia following IVF, but to a null association between IVF and lymphoma. The proportion of leukemia cases conceived through IVF was 3% in Greece and 2.7% in Sweden; prevalence of IVF in matched controls was 1.8% and 1.6%, respectively. In combined multivariable analyses, the increased risk of leukemia was confined to age below 3.8 years (OR = 2.21; 95% confidence interval, CI: 1.27-3.85) and to acute lymphoblastic leukemia (ALL) (OR = 1.77; 95% CI: 1.06-2.95) with no sufficient evidence of excess risk for other leukemias (OR = 1.34; 95% CI: 0.38-4.69). Following IVF, OR for ALL was 2.58 (95% CI: 1.37-4.84) before age 3.8 and 4.29 (95% CI: 1.49-12.37) before age 2 years.

CONCLUSIONS

IVF seems to be associated with increased risk of early onset ALL in the offspring.

Parental infertility, infertility treatment and hepatoblastoma: a report from the Children's Oncology Group

BACKGROUND

A recent study suggested a markedly increased risk of hepatoblastoma (HB) among children conceived with treatment for infertility. However, it is not clear whether this finding is confounded by the association between HB and low birthweight (LBW).

METHODS

Associations between parental infertility and its treatment and HB were examined using data from a case-control study conducted through the Children's Oncology Group (COG). Telephone interviews were completed for 383 mothers of cases diagnosed with HB at US COG institutions between January 2000 and December 2008 and for 387 mothers of controls recruited through state birth registries. Logistic regression was used to examine possible associations.

RESULTS

After adjusting for birthweight and other potential confounders, no significant association was found for any of the measures of parental infertility or its treatment. In HB cases conceived through assisted reproductive technology (ART), 4 of 16 also had Beckwith-Wiedemann syndrome (BWS) compared with 9 of 365 in HB cases without ART.

CONCLUSIONS

Little evidence of an association between parental infertility or its treatment and HB was found. The relationship found in a previous study could be due to LBW and BWS which are risk factors for HB and also associated with parental infertility and its treatment.

Hepatoblastoma: recent developments in research and treatment

Hepatoblastoma is the most common liver tumor of early childhood. According to recent studies its incidence seems to be increasing in North America and Europe. Since new histological variants have been described recently the formerly clear-cut distinction of hepatoblastoma and hepatocellular carcinoma may not be valid anymore and a new histological classification will be inaugurated by an international working group. Recent research identified prognostically relevant gene signatures as well as potential molecular targets for therapy of hepatoblastoma. The multicentric study groups in the USA, Europe and Japan recommend cisplatin based chemotherapy for neoadjuvant and adjuvant treatment. However, their risk stratification systems and general treatment strategies differ substantially. Therefore the four groups agreed to pool their patients' data for an analysis of prognostic criteria which can be used for defining common risk groups. While 90% of standard risk and 65% of high risk hepatoblastomas can be cured, the still dismal outcome of multifocal disseminated and metastasising tumors warrants the investigation of new cytotoxic drugs and substances against specific molecular targets.

Hepatoblastoma in the Nordic countries

Little is known about the etiology of hepatoblastoma. Because of the young age at diagnosis, several studies have looked at various birth characteristics. The purpose of our study was to investigate the incidence of hepatoblastoma in the Nordic countries and the association between selected birth characteristics and hepatoblastoma. Data from national cancer registries and birth registries in Denmark, Sweden, Norway and Finland 1985-2006 was used. Overall, 155 children with hepatoblastoma aged 0-14 years were included and individually matched to five controls drawn randomly from national population registries. The incidence rate of hepatoblastoma was 1.7 per million person-years with a predominance of boys (1.5:1). Incidence rate was highest before the age of 1 year (8.3 per million person-years). A higher risk of hepatoblastoma was found in children with birth weight <1,500 g [odds ratio (OR) = 9.5; 95% confidence interval (CI): 2.3-38.2], born preterm in week 22-32 (OR = 4.5; CI: 1.8-11.5) and Apgar scores <7 after 1 min (OR = 3.1; CI: 1.3-7.1) and 5 min (OR = 7.5; CI: 1.8-32.4). A doubling in risk was found in children who were large for gestational age (OR = 2.3; CI: 1.0-5.3). No associations were found with birth order, maternal age or maternal smoking. Our study indicates that intrauterine and/or neonatal factors are associated with increased risk of hepatoblastoma. These may include low birth weight and asphyxia leading to neonatal intensive care. Alternatively, the factors may be a consequence of hepatoblastoma developing in utero.

The 5-minute Apgar score as a predictor of childhood cancer: a population-based cohort study in five million children

OBJECTIVE

The aetiology of childhood cancer remains largely unknown but recent research indicates that uterine environment plays an important role. We aimed to examine the association between the Apgar score at 5 min after birth and the risk of childhood cancer.

DESIGN

Nationwide population-based cohort study.

SETTING

Nationwide register data in Denmark and Sweden.

STUDY POPULATION

All live-born singletons born in Denmark from 1978 to 2006 (N=1 771 615) and in Sweden from 1973 to 2006 (N=3 319 573). Children were followed up from birth to 14 years of age.

MAIN OUTCOME MEASURES

Rates and HRs for all childhood cancers and for specific childhood cancers.

RESULTS

A total of 8087 children received a cancer diagnosis (1.6 per 1000). Compared to children with a 5-min Apgar score of 9-10, children with a score of 0-5 had a 46% higher risk of cancer (adjusted HR 1.46, 95% CI 1.15 to 1.89). The potential effect of low Apgar score on overall cancer risk was mostly confined to children diagnosed before 6 months of age. Children with an Apgar score of 0-5 had higher risks for several specific childhood cancers including Wilms' tumour (HR 4.33, 95% CI 2.42 to 7.73).

CONCLUSIONS

A low 5 min Apgar score was associated with a higher risk of childhood cancers diagnosed shortly after birth. Our data suggest that environmental factors operating before or during delivery may play a role on the development of several specific childhood cancers.

Inhibition of autophagy may suppress the development of hepatoblastoma

Hepatoblastoma (HB) is a rare cancer but represents the most common liver malignancy in children under 3 years of age. Nevertheless, a clear understanding of the pathogenesis is lacking. Although the treatment of HB has been dramatically improved by combining chemotherapy regimens with surgery, its fatal outcome of fast development and recurrence makes new treatment strategies for HB, based on an improved understanding of the pathogenesis, essential. Autophagy is believed to be important in the progression of cancers. However, the role of autophagy in HB remains to be elucidated. Here, we show that autophagy is activated in HB tissues and cells under the conditions of starvation or chemotherapy, coupled with the over-expression of autophagic-related genes BECN1 and ATG5. Suppression of autophagy with pharmacological agents and small interfering RNAs significantly increased cell apoptosis and retarded proliferation in response to nutrition deprivation and treatment with chemotherapeutics. Our data demonstrate that the BECN1 and ATG5-dependent phosphoinositide 3-kinase (PI3K) signaling pathway is essential for the survival of HB cells and their tolerance to chemotherapy and starvation-induced death, and suggests that modifying such autophagic genes may suppress the development of HB, thus offering a therapeutic potential for patients with HB.

Hepatoblastoma and prune belly syndrome: a potential association

Prune belly syndrome (PBS) is a congenital anomaly characterized by the clinical triad of lax abdominal musculature, bilateral cryptorchidism, and abnormalities of the kidney and urinary tract. Previous reports of malignancy in patients with PBS have been limited to germ cell tumors. Hepatoblastoma (HBL) is the most common hepatic malignancy of childhood, affecting approximately 100 children each year in the USA. We describe a set of 4 pediatric patients with PBS and HBL. All individuals were born after 2002. These subjects lacked genetic, natal, or environmental factors known to confer risk of HBL. The occurrence of PBS and HBL in these patients constitutes a novel potential association.

Altered microRNA Expression Patterns in Hepatoblastoma Patients

Liver cancers in children are rare representing only 1.1% of malignancies, with an annual incidence rate of 1.5 cases per million. Hepatoblastoma and hepatocellular carcinomas are the most common malignancies of the liver occurring in young people aged 15 years or younger. Molecular basis of both tumors are still unclear, and common markers (i.e., CTNNB1, APC, IGF-2) are not always useful in the characterization of sporadic forms; in this respect, microRNA recently associated with carcinogenesis could play a pivotal role in their onset. CTNNB1 and APC were analyzed by sequencing, and IGF-2 promoter methylation status was assessed by methylation-specific polymerase chain reaction. MicroRNA expression was assayed by microarray and quantitative reverse transcription-polymerase chain reaction in hepatoblastoma samples. Although few genomic alterations were detected in ours samples, an altered expression of somemicroRNA in hepatoblastoma was observed. Unsupervised clustering shows that microRNA profile can distinguish tumor from nontumor tissues. Further analyses of microRNA contents in hepatoblastoma compared with hepatocellular carcinoma highlighted four upregulated microRNA (miR-214, miR-199a, miR-150 [P < .01], and miR-125a [P < .05]) and one downregulated microRNA (miR-148a [P < .01]). In conclusion, although our samples were poorly informative from a genetic point of view, they showed a peculiar microRNA expression pattern compared with nontumor tissues and hepatocellular carcinoma. MicroRNA could represent valid markers for the classification of pediatric liver tumors.

Liver neoplasia in children

Management of pediatric liver tumors has significantly improved over the last 2 decades. The management options for hepatocelluar carcinoma (HCC) are not well defined. In the pediatric context, the main clinical aims are to reduce chemotherapy toxicity (predominantly ototoxicity and nephrotoxicity) in children treated for hepatoblastoma and to investigate additional modes of treatment for HCC. An increasing number of children develop HCC in the background of chronic liver disease, and screening methods need to be better observed.

Childhood cancer in relation to parental race and ethnicity: a 5-state pooled analysis

BACKGROUND

Children of different racial/ethnic backgrounds have varying risks of cancer. However, to the authors' knowledge, few studies to date have examined cancer occurrence in children of mixed ancestry.

METHODS

This population-based case-control study examined cancer among children aged <15 years using linked cancer and birth registry data from 5 US states from 1978 through 2004. Data were available for 13,249 cancer cases and 36,996 controls selected from birth records. Parental race/ethnicity was determined from birth records. Logistic regression analysis was used to examine the association of cancer with different racial/ethnic groups.

RESULTS

Compared with whites, blacks had a 28% decreased risk of cancer (odds ratio [OR], 0.72; 95% confidence interval [95% CI], 0.65-0.80), whereas both Asians and Hispanics had an approximate 15% decrease. Children of mixed white/black ancestry also were found to be at decreased risk (OR, 0.71; 95% CI, 0.56-0.90), but estimates for mixed white/Asian and white/Hispanic children did not differ from those of whites. Compared with whites: 1) black and mixed white/black children had decreased ORs for acute lymphoblastic leukemia (OR, 0.39 [95% CI, 0.31-0.49] and OR, 0.58 [95% CI, 0.37-0.91], respectively); 2) Asian and mixed white/Asian children had decreased ORs for brain tumors (OR, 0.51 [95% CI, 0.39-0.68] and OR, 0.79 [95% CI, 0.54-1.16], respectively); and 3) Hispanic and mixed white/Hispanic children had decreased ORs for neuroblastoma (OR, 0.51 [95% CI, 0.42-0.61] and OR, 0.67 [95% CI, 0.50-0.90], respectively).

CONCLUSIONS

Children of mixed ancestry tend to have disease risks that are more similar to those of racial/ethnic minority children than the white majority group. This tendency may help formulate etiologic studies designed to study possible genetic and environmental differences more directly.

Parental educational attainment as an indicator of socioeconomic status and risk of childhood cancers

Background:

Little has been reported on socioeconomic (SES) patterns of risk for most forms of childhood cancer.

Methods:

Population-based case–control data from epidemiological studies of childhood cancer conducted in five US states were pooled and associations of maternal, paternal and household educational attainment with childhood cancers were analysed. Odds ratios (ORs) and 95% confidence intervals were estimated using logistic regression, controlling for confounders.

Results:

Although there was no association with parental education for the majority of cancers evaluated, there was an indication of a positive association with lower education for Hodgkin's and Burkitt's lymphoma and Wilm's tumour, with the ORs ranging from 1.5 to >3.0 times that of more educated parents. A possible protective effect was seen for lower parental education and astrocytoma and hepatoblastoma, with ORs reduced by 30 to 40%.

Conclusions:

These study results should be viewed as exploratory because of the broad nature of the SES assessment, but they give some indication that childhood cancer studies might benefit from a more thorough assessment of SES.

Infant leukemia and parental infertility or its treatment: a Children's Oncology Group report

BACKGROUND

Little is known about the potential risk factors for infant leukemia. With its very young age at diagnosis, exposures occurring in the perinatal period are suspected. Parental infertility and infertility treatment have been studied with regard to childhood cancer in general, but rarely in individual cancer subtypes.

METHODS

A case-control study of infant leukemia was conducted through the Children's Oncology Group, including cases diagnosed from January 1996 to December 2006 and controls selected through random digit dialing and birth certificate tracing. Maternal phone interviews were conducted to obtain information about infertility, infertility treatment and demographic factors. All cases as well as subgroups defined by mixed lineage leukemia (MLL) translocation status and leukemia subtype were examined. Statistical analysis was performed using multivariate logistic regression models.

RESULTS

No significant associations between infertility or its treatment and combined infant leukemia were found. In subgroup analyses, there was a significant increase in the risk of MLL--leukemia for children born to women not trying to conceive compared with those trying for <1 year for all types combined [odds ratio (OR) = 1.62, 95% confidence interval (CI) = 1.01-2.59] and for acute lymphoblastic leukemia (OR = 2.50, 95% CI = 1.36-4.61).

CONCLUSIONS

There were no positive associations between parental infertility or infertility treatment and infant leukemia. While this is the largest study to date, both selection and recall bias may have impacted the results. However, for infant leukemia, we can potentially rule out large increases in risk associated with parental infertility or its treatment.

Birth weight, sex and childhood cancer: A report from the United Kingdom Childhood Cancer Study

Birth weight has been linked to the risk of developing childhood cancer, in particular childhood leukaemia. However, despite many childhood cancers having a male predominance and boys generally weighing more than girls at birth few studies have reported sex-specific associations. The relationship between birth weight and childhood cancer risk was examined using information from a national case-control study. Children (0-14 years) newly diagnosed with cancer in GB were ascertained between 1991 and 1996 (n=3651) and for comparison, controls matched on sex, month and year of birth were identified from primary care population registers (n=6337). Birth weights were obtained from the Office of National Statistics for all targeted subjects born in England and Wales. Overall, cases were, on average, 30 g heavier at birth than controls (p=0.003) with differences seen by cancer type; those diagnosed with hepatic tumours weighing around 500 g less than controls at birth (p<0.0001) and those with leukaemia being, on average, 50 g heavier than those without (p=0.001). An interaction between birth weight and sex was found for acute leukaemia (chi(2)=11.2, p=0.04) and when data were stratified by sex, an association between high birth weight and risk of ALL was seen with girls (>4000 g, OR 1.86, 95% CI 1.38-2.50, chi(2) for trend 20.2, p<0.0001). Our results support the hypothesis that birth weight is an important determinant for childhood cancer. In addition, the data are consistent with the notion that childhood leukaemia has a prenatal origin.

Cancer risk among children with very low birth weights

OBJECTIVE

The risk of hepatoblastoma is strongly increased among children with very low birth weight (<1500 g). Because data on very low birth weight and other childhood cancers are sparse, we examined the risk of malignancy with very low birth weight in a large data set.

METHODS

We combined case-control data sets created by linking the cancer and birth registries of California, Minnesota, New York, Texas, and Washington states, which included 17672 children diagnosed as having cancer at 0 to 14 years of age and 57966 randomly selected control subjects. Unconditional logistic regression analysis was used to examine the association of cancer with very low birth weight and moderately low birth weight (1500-1999 g and 2000-2499 g, respectively), compared with moderate/high birth weight (>or=2500 g), with adjustment for gender, gestational age, birth order, plurality, maternal age, maternal race, state, and year of birth.

RESULTS

Most childhood cancers were not associated with low birth weights. However, retinoblastomas and gliomas other than astrocytomas and ependymomas were possibly associated with very low birth weight. The risk of other gliomas was also increased among children weighing 1500 to 1999 g at birth.

CONCLUSIONS

These data suggested no association between most cancers and very low birth weight, with the exception of the known association of hepatoblastoma and possibly moderately increased risks of other gliomas and retinoblastoma, which may warrant confirmation.

Parental age and risk of childhood cancer: a pooled analysis

BACKGROUND

Few risk factors for childhood cancer are well-established. We investigated whether advancing parental age increases childhood cancer risk.

METHODS

We assessed the relationship between parental age and childhood cancer in a case-control study using pooled population-based data. Our pooling was based on linked cancer and birth registry records from New York, Washington, Minnesota, Texas, and California. Subjects included 17,672 cancer cases diagnosed at ages 0-14 years during 1980-2004 and 57,966 controls born during 1970-2004. Individuals with Down syndrome were excluded. Odds ratios and 95% confidence intervals were calculated by logistic regression for the association between parental age and childhood cancer after adjustment for sex, birth weight, gestational age, birth order, plurality, maternal race, birth year, and state.

RESULTS

Positive linear trends per 5-year maternal age increase were observed for childhood cancers overall (odds ratio = 1.08 [95% confidence interval = 1.06-1.10]) and 7 of the 10 most frequent diagnostic groups: leukemia (1.08 [1.05-1.11]), lymphoma (1.06 [1.01-1.12]), central nervous system tumors (1.07 [1.03-1.10]), neuroblastoma (1.09 [1.04-1.15]), Wilms' tumor (1.16 [1.09-1.22]), bone tumors (1.10 [1.00-1.20]), and soft tissue sarcomas (1.10 [1.04-1.17]). No maternal age effect was noted for retinoblastoma, germ cell tumors, or hepatoblastoma. Paternal age was not independently associated with most childhood cancers after adjustment for maternal age.

CONCLUSIONS

Our results suggest that older maternal age increases risk for most common childhood cancers. Investigation into possible mechanisms for this association is warranted.

Childhood cancer among twins and higher order multiples

Although several studies have found no change or a decreased risk of childhood cancer in twins, few have controlled for potential confounders such as birth weight. We examined the association of birth plurality and childhood cancer in pooled data from five U.S. states (California, Minnesota, New York, Texas, and Washington) using linked birth-cancer registry data. The data, excluding children with Down syndrome or who died before 28 days of life, included 17,672 cases diagnosed from 1980 to 2004 at ages 28 days to 14 years and 57,966 controls with all cases and controls born from 1970 to 2004. Analyses were restricted to children weighing Collapse

Key Words

• childhood cancer
• twins
• multiple birth
• case-control
• pooled data

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MESH Headings

• Adolescent
• Case-Control Studies
• Child
• Child, Preschool
• Diseases in Twins/epidemiology
• Female
• Humans
• Infant
• Infant, Newborn
• Kidney Neoplasms/epidemiology
• Logistic Models
• Male
• Multiple Birth Offspring
• Neoplasms/epidemiology
• Registries
• Retinal Neoplasms/epidemiology
• Retinoblastoma/epidemiology
• Risk Factors
• United States/epidemiology
• Wilms Tumor/epidemiology

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Grants

• R01CA717450 NCI NIH HHS
• R01 CA092670-04 NCI NIH HHS
• U58 DP000783 NCCDPHP CDC HHS
• R01CA92670 NCI NIH HHS
• R01 CA092670 NCI NIH HHS
• T32 CA099936-04 NCI NIH HHS
• N01 CN005230 NCI NIH HHS
• R01 CA071745-04 NCI NIH HHS
• T32 CA099936 NCI NIH HHS

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Affiliation(s)

Susan E. Puumala Division of Epidemiology/Clinical Research, Department of Pediatrics, University of Minnesota
Susan E. Carozza Department of Epidemiology and Biostatistics, Texas A&M University
Eric J. Chow Fred Hutchinson Cancer Research Center
Erin E. Fox Cancer Epidemiology and Surveillance Branch, Texas Department of State Health Services
Scott Horel Department of Epidemiology and Biostatistics, Texas A&M University
Kimberly J. Johnson Division of Epidemiology/Clinical Research, Department of Pediatrics, University of Minnesota
Colleen McLaughlin New York State Cancer Registry, New York Department of Health
Beth A. Mueller Fred Hutchinson Cancer Research Center
Peggy Reynolds Northern California Cancer Center
Julie Von Behren Northern California Cancer Center
Logan G. Spector Division of Epidemiology/Clinical Research, Department of Pediatrics, University of Minnesota Masonic Cancer Center, University of Minnesota

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Liver tumors: pediatric population

Liver tumors in childhood are rare and are typically not detected clinically until they reach a large size and often spread within the organ or metastasize. This can make surgical resection problematic, and almost all of them require extirpation for cure. With very effective chemotherapy for hepatoblastoma and to some extent for sarcomas, many cancers can be shrunk to permit partial hepatectomy, but for most hepatocarcinomas, some of the other malignancies, and even some benign proliferations, their location at the hilum and multiplicity of masses in multiple lobes make transplantation the treatment of choice. Major advances in diagnostic imaging, especially enhanced computed tomography and magnetic resonance imaging, permit a preoperative choice of resection versus transplantation to be achieved in almost all instances, and for the remainder, intraoperative ultrasonography can further help to determine the most desirable approach. The outcome is very much better in the case of hepatoblastoma when transplantation is a primary modality rather than following unsuccessful attempts at resection. In this review, transplantation for liver tumors in children is considered from all aspects, including the importance of screening for tumors whenever possible to avoid the need for transplantation.

Perinatal risk factors for neuroblastoma

Neuroblastoma is the most common cancer among infants, suggesting an etiologic role for prenatal factors. In this case-cohort study, neuroblastoma cases (n = 529) diagnosed between 1985 and 2001 were identified from the New York State Cancer Registry and were matched to the electronic birth records for 1983-2001 from New York State and New York City. Controls (n = 12,010) were selected from the same birth cohorts. Analysis was stratified by age at diagnosis, with one to six months (younger infants), seven to 18 months (older infants), and older than 18 months (older children) analyzed separately. Perinatal exposure data was obtained from the birth certificates. No risk factors were identified to be consistently associated with risk across all three age groups. Generally, more risk factors were identified as associated with neuroblastoma among younger infants relative to older ages, including high birth weight, heavier maternal gestational weight gain, maternal hypertension, older maternal age, ultrasound, and respiratory distress. Among older infants, low birth weight was associated with increased risk while heavier maternal gestational weight gain was protective. In the oldest age group, first born status, primary cesarean delivery, prolonged labor and premature rupture of the membranes were associated with increased risk.

Erythrocytosis and pleural effusion associated with a hepatoblastoma in a Thoroughbred yearling

A 10-month-old Thoroughbred filly was presented with a 2-month history of recurrent fever and pleural effusion. Major clinical findings were pyrexia and congested mucous membranes. Clinical pathology tests revealed an erythrocytosis, hyperfibrinogenaemia and hyperglobulinaemia. Pleural fluid was seen on ultrasonographic examination of the thorax and analysis of a thoracocentesis sample indicated a lymphocytic, modified transudate. A transtracheal aspirate was normal. The erythrocytosis persisted despite IV fluid therapy. Arterial blood gas analysis and bone marrow aspirate were normal. These findings were indicative of secondary inappropriate erythrocytosis. Ultrasonographic examination of the abdomen showed a large encapsulated heterogeneous mass in the left lobe of the liver. Histopathological evaluation of a biopsy of the mass was indicative of a hepatic carcinoma. The filly was euthanased and necropsy confirmed the presence of a hepatic tumour with no evidence of systemic metastasis. Further histopathological evaluation confirmed the tumour to be an embryonal macrotrabecular epithelial-type hepatoblastoma, a type of hepatoblastoma that has not previously been reported in a horse.

[Risks factors for pediatric malignant liver tumors]

OBJECTIVE

Pediatric Hepatic Malignancies (PHMs) are the result of the interaction between constitutional and environmental risk factors (RFs). We review the evidence on the main RFs associated to PHMs.

METHOD

Systematic review of the literature published in the last 25 years on Medline, Embase, Cancerlit, Lilacs and SciElo using the following key words: "etiology/risk factor/epidemiology" and "malignant liver tumors/hepatic cancer" or "hepatoblastoma/hepatocarcionoma".

RESULTS

PHMs account for 1 % of all pediatric malignancies. The main types, hepatoblastoma (HB) and hepatocarcionma (HCC) make up 98-99 % of PHM. The main constitutional RFs are: a) Beckwith-Wiedemann (BW) syndrome; b) isolated hemihyperplasia syndrome (IHS); c) adenomatous polyps of the colon; d) hemochromatosis; e) Hereditary Tyrosinemia Type 1; f) a -1-antitrypsin deficiency; g) porphyrias; h) cirrhosis; i) nonalcoholic steatosis; and j) primary sclerosing cholangitis. The main environmental RFs are: a) hepatitis B virus (HBV) and C virus (HCV); b) B1 aflatoxin (B1AF); c) ionizing radiation; d) alcohol; e) hormonal treatments; f) occupational exposure to pesticides, solvents, vinyl chloride and metals; g) smoking; h) arsenic; i) prematury and very low birth weight; and j) trematodes.

CONCLUSIONS

The clinical, analytical and ultrasound screening facilitate the early diagnosis of HB in the previously mentioned genetic syndromes, particularly BW and IHS during the first years of life. HBV universal vaccination of newborns provides the biggest opportunity to prevent a substantial proportion of PHMs. Also systematic monitoring of HBV and HCV in blood, hemoderivates, donated organs and drug addicts, are very useful. Other effective measures are: the reduction/elimination of B(1)AF in food, zero alcohol intake during childhood and adolescence as well decreasing prenatal exposure to the tobacco, solvents, pesticides, vinyl chloride, metals, ionizing radiation and hormonal treatments.

Perinatal risk factors for hepatoblastoma

We confirmed the strong association of hepatoblastoma with very low birth weight (relative risk <1000 g vs >or=2000 g=25.6; 95% confidence interval: 7.70-85.0) and demonstrated independent associations with congenital abnormalities and maternal Asian race in a population-based Minnesota study that included 36 cases and 7788 controls.