The Childhood Leukemia International Consortium

Abstract Background : Acute leukemia is the most common cancer in children under 15 years of age; 80% are acute lymphoblastic leukemia (ALL) and 17% are acute myeloid leukemia (AML). Childhood leukemia shows further diversity based on cytogenetic and molecular characteristics, which may relate to distinct etiologies. Case–control studies conducted worldwide, particularly of ALL, have collected a wealth of data on potential risk factors and in some studies, biospecimens. There is growing evidence for the role of infectious/immunologic factors, fetal growth, and several environmental factors in the etiology of childhood ALL. The risk of childhood leukemia, like other complex diseases, is like…

The Role of Epidemiology in Cancer Risk Assessment of Nonionizing Radiation

Statistical power of disease cluster and clustering tests for rare diseases: A simulation study of point sources

Abstract Two recent epidemiological studies on clustering of childhood leukemia showed different results on the statistical power of disease cluster and clustering tests, possibly an effect of spatial data aggregation. Eight different leukemia cluster scenarios were simulated using individual addresses of all 1,009,332 children living in Denmark in 2006. For each scenario, a number of point sources were defined with an increased risk ratio at centroid, decreasing linearly to 1.0 at the edge; aggregation levels were administrative units of Danish municipalities and squares of 5, 12.5 and 25 km 2 . Six statistical methods were compared. Generally, statistical power decreased with increasing s…

Impact of the COVID-19 pandemic on incidence, time of diagnosis and delivery of healthcare among paediatric oncology patients in Germany in 2020: Evidence from the German Childhood Cancer Registry and a qualitative survey.

ABSTRACT Background The indirect impact of the COVID-19 pandemic on cancer care and timely diagnosis is of increasing concern. We investigated the impact of the COVID-19 pandemic on incidence, time of diagnosis and delivery of healthcare among paediatric oncology patients in Germany in 2020. Methods We analysed incident paediatric cancer cases diagnosed in 0- to 17-year olds in Germany in 2020 using data of the German Childhood Cancer Registry. Absolute numbers and age-standardised incidence rates (ASR) in 2020 were compared to the previous five years (2015–2019). Moreover, we conducted a survey with open-ended questions, gathering perceptions of the diagnostic process and healthcare delive…

An evaluation of exposure metrics in an epidemiologic study on radio and television broadcast transmitters and the risk of childhood leukemia.

Electric field strength values calculated by wave propagation modeling were applied as an exposure metric in a case–control study conducted in Germany to investigate a possible association between radio frequency electromagnetic fields (RF-EMF) emitted from television and radio broadcast transmitters and the risk of childhood leukemia. To validate this approach it was examined at 850 measurement sites whether calculated RF-EMF are an improvement to an exposure proxy based on distance from the place of residence to a transmitter. Further, the agreement between measured and calculated RF-EMF was explored. For dichotomization at the 90% quantiles of the exposure distributions it was found that…

Maternal Supplementation with Folic Acid and Other Vitamins and Risk of Leukemia in Offspring

Maternal prenatal supplementation with folic acid and other vitamins has been inconsistently associated with a reduced risk of childhood acute lymphoblastic leukemia (ALL). Little is known regarding the association with acute myeloid leukemia (AML), a rarer subtype.We obtained original data on prenatal use of folic acid and vitamins from 12 case-control studies participating in the Childhood Leukemia International Consortium (enrollment period: 1980-2012), including 6,963 cases of ALL, 585 cases of AML, and 11,635 controls. Logistic regression was used to estimate pooled odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for child's age, sex, ethnicity, parental education, and s…

Comparison of Studies on Mobile Phone Use and Risk of Tumors

published results of ameta-analysis of studies on mobile phone use and risk of tumors. Intheir analysis, the authors included 23 case-control studies, covering abroad spectrum of tumor entities including uveal melanoma, testicu-lar cancer, parotid gland tumors, and brain tumors.However, the authors give no rationale for pooling these hetero-geneous, biologically rather diverse cancer sites, for which the local-ized exposure from the use of mobile phones is completely different.The key difference between this particular meta-analysis com-pared with earlier ones is the use of a quality score. The use of qualityscoreshasbeenreportedtobea“formofsubjectivitymasqueradingasobjectivity”andithasbeen…

Epidemiologie, Ätiologie, Prävention

Welches sind die Ursachen von Krebserkrankungen im Kindes- und Jugendalter? Welche Rolle spielen Umweltfaktoren bei der Entstehung dieser Erkrankungen? Eine Grundlage zur Beantwortung dieser Fragen bilden epidemiologische Krebsregister, wie etwa das 1980 auf Initiative der deutschsprachigen padiatrischen Onkologen gegrundete Deutsche Kinderkrebsregister. Mit einem solchen Register kann z. B. beantwortet werden, wie haufig Krebserkrankungen auftreten, ob Veranderungen in der Auftretenshaufigkeit zu beobachten sind oder ob sich die Prognose generell verbessert hat. Dies ist dank der guten Zusammenarbeit der Krebsregister untereinander moglich und wird intensiv ge nutzt. Aufbauend auf der dami…

The INTERPHONE study: design, epidemiological methods, and description of the study population

The very rapid worldwide increase in mobile phone use in the last decade has generated considerable interest in the possible health effects of exposure to radio frequency (RF) fields. A multinational case-control study, INTERPHONE, was set-up to investigate whether mobile phone use increases the risk of cancer and, more specifically, whether the RF fields emitted by mobile phones are carcinogenic. The study focused on tumours arising in the tissues most exposed to RF fields from mobile phones: glioma, meningioma, acoustic neurinoma and parotid gland tumours. In addition to a detailed history of mobile phone use, information was collected on a number of known and potential risk factors for t…

Childhood acute lymphoblastic leukaemia and birthweight: Insights from a pooled analysis of case–control data from Germany, the United Kingdom and the United States

Abstract Background Heavy birthweight is one of the few established risk factors for childhood acute lymphoblastic leukaemia (ALL). To provide new insight into this relationship, particularly at the extremes ( 4500 g), we pooled data from three of the largest childhood cancer case–control studies ever conducted. Methods Birthweight and gestational age on 4075 children with ALL and 12,065 controls were collected during the course of three studies conducted in the USA, the UK and Germany in the 1990s. Information was obtained from mothers at interview, and the impact of bias was evaluated using the UK study which accessed birth registrations of participants and non-participants. Odds ratios (…

The Intracranial Distribution of Gliomas in Relation to Exposure From Mobile Phones: Analyses From the INTERPHONE Study

When investigating the association between brain tumors and use of mobile telephones, accurate data on tumor position are essential, due to the highly localized absorption of energy in the human brain from the radio-frequency fields emitted. We used a point process model to investigate this association using information that included tumor localization data from the INTERPHONE Study (Australia, Canada, Denmark, Finland, France, Germany, Israel, Italy, Japan, New Zealand, Norway, Sweden, and the United Kingdom). Our main analysis included 792 regular mobile phone users diagnosed with a glioma between 2000 and 2004. Similar to earlier results, we found a statistically significant association …

The “Mainzer EMF-Wachhund”: results from a watchdog project on self-reported health complaints attributed to exposure to electromagnetic fields

The "Mainzer EMF-Wachhund," a watchdog project, offered a system of self-notification of health complaints attributed to exposures to electromagnetic fields (EMFs) to a population of a part of Germany with about 4 million inhabitants. By using a self-administered questionnaire, which was provided online and for download from the Internet, 192 persons reported such health complaints in the period from October 2003 to March 2005. Of these, 56% classified themselves as electromagnetic hypersensitive (EH). Predictors of this self classification were being affected by all kinds of EMF rather than single EMF sources and being female. On average, EH subjects reported a high degree of suffering, 77…

RE: "RADIO-FREQUENCY RADIATION EXPOSURE FROM AM RADIO TRANSMITTERS AND CHILDHOOD LEUKEMIA AND BRAIN CANCER"

Medical exposure to ionising radiation and the risk of brain tumours: Interphone study group, Germany

Abstract Background The role of exposure to low doses of ionising radiation in the aetiology of brain tumours has yet to be clarified. The objective of this study was to investigate the association between medically or occupationally related exposure to ionising radiation and brain tumours. Methods We used self-reported medical and occupational data collected during the German part of a multinational case–control study on mobile phone use and the risk of brain tumours (Interphone study) for the analyses. Results For any exposure to medical ionising radiation we found odds ratios (ORs) of 0.63 (95% confidence interval (CI) = 0.48–0.83), 1.08 (95% CI = 0.80–1.45) and 0.97 (95% CI = 0.54–1.75)…

Cellular Phones, Cordless Phones, and the Risks of Glioma and Meningioma (Interphone Study Group, Germany)

The widespread use of cellular telephones has generated concern about possible adverse health effects, particularly brain tumors. In this population-based case-control study carried out in three regions of Germany, all incident cases of glioma and meningioma among patients aged 30–69 years were ascertained during 2000–2003. Controls matched on age, gender, and region were randomly drawn from population registries. In total, 366 glioma cases, 381 meningioma cases, and 1,494 controls were interviewed. Overall use of a cellular phone was not associated with brain tumor risk; the respective odds ratios were 0.98 (95% confidence interval (CI): 0.74, 1.29) for glioma and 0.84 (95% CI: 0.62, 1.13)…

erman case control study on childhood leukaemia - Basic considerations, methodology and summary of the results

In order to explore potential risk factors of childhood leukaemia, a case control study was performed including all incident cases from 1992 to 1994. The study was based on the German Childhood Cancer Registry. It was restricted to cases from West Germany and extended retrospectively until 1980 for children who were living in regions covered by a previous incidence study on nuclear installations (21). The study was conducted in close correspondence with a preceding case control study in Lower Saxony (13). Results of this study and of others published in the literature were used to define explicit hypotheses for the present study. This paper presents the methodology of the study and gives an…

Mobile phone base stations and adverse health effects: phase 1 of a population-based, cross-sectional study in Germany

Objective: The aim of this first phase of a cross-sectional study from Germany was to investigate whether proximity of residence to mobile phone base stations as well as risk perception is associated with health complaints. Methods: The researchers conducted a population-based, multi-phase, cross-sectional study within the context of a large panel survey regularly carried out by a private research institute in Germany. In the initial phase, reported on in this paper, 30 047 persons from a total of 51 444 who took part in the nationwide survey also answered questions on how mobile phone base stations affected their health. A list of 38 health complaints was used. A multiple linear regression…

Occupation and risk of glioma, meningioma and acoustic neuroma: results from a German case-control study (interphone study group, Germany)

Background: Several epidemiological studies have investigated the association between occupation and brain tumour risk, but results have been inconclusive. We investigated the association between six occupational categories defined a priori: chemical, metal, agricultural, construction, electrical/electronic and transport, and the risk of glioma, meningioma and acoustic neuroma. Methods: In a population-based case-control study involving a total of 844 cases and 1688 controls conducted from 2000 to 2003, detailed information on life-long job histories was collected during personal interviews and used to create job calendars for each participant. Job title, job activity, job number, and the s…

High-birth weight and other risk factors for Wilms tumour: results of a population-based case-control study.

Wilms tumour, or nephroblastoma, is one of the childhood cancers included in two recent population-based case-control studies in West Germany. Altogether, 177 children under the age of 10 years with Wilms tumour diagnosed between 1988 and 1994 and 2006 control children sampled from population registration files participated. Information on potential risk factors was obtained from the parents using a questionnaire and by subsequent telephone interview. We found an association with a high birth weight >4000 g (odds ratio 1.58; 95% confidence interval 1.01–2.48), which was somewhat stronger for children aged 2 years or older. Findings for young maternal age at birth and certain parental occupa…

Validation of short term recall of mobile phone use for the Interphone study

Aim: To validate short term recall of mobile phone use within Interphone, an international collaborative case control study of tumours of the brain, acoustic nerve, and salivary glands related to mobile telephone use. Methods: Mobile phone use of 672 volunteers in 11 countries was recorded by operators or through the use of software modified phones, and compared to use recalled six months later using the Interphone study questionnaire. Agreement between recalled and actual phone use was analysed using both categorical and continuous measures of number and duration of phone calls. Results: Correlations between recalled and actual phone use were moderate to high (ranging from 0.5 to 0.8 acros…

Extremely low frequency magnetic fields in residences in Germany. Distribution of measurements, comparison of two methods for assessing exposure, and predictors for the occurrence of magnetic fields above background level.

We examined the results of 1,835 magnetic field measurements in German residences conducted between November 1997 and September 1999. The measurements were part of an epidemiological study on the relationship between magnetic fields and childhood leukemia. We performed a fixed-location measurement of the magnetic field at 50 Hz and 16 2/3 Hz (frequency of the German railway system) over 24 h in the child's bedroom in the residence of each study participant. In addition, we conducted a second 24 h-measurement in the living room at 50 Hz, and spot measurements while walking through all rooms of the respective dwelling. Median 50 Hz magnetic fields above 0.2 muT were found to be infrequent in …

Diagnostic radiological examinations and risk of intracranial tumours in adults—findings from the Interphone Study

Abstract Background Exposure to high doses of ionizing radiation is among the few well-established brain tumour risk factors. We used data from the Interphone study to evaluate the effects of exposure to low-dose radiation from diagnostic radiological examinations on glioma, meningioma and acoustic neuroma risk. Methods Brain tumour cases (2644 gliomas, 2236 meningiomas, 1083 neuromas) diagnosed in 2000–02 were identified through hospitals in 13 countries, and 6068 controls (population-based controls in most centres) were included in the analysis. Participation across all centres was 64% for glioma cases, 78% for meningioma cases, 82% for acoustic neuroma cases and 53% for controls. Informa…

A Pooled Analysis of Extremely Low-Frequency Magnetic Fields and Childhood Brain Tumors

Pooled analyses may provide etiologic insight about associations between exposure and disease. In contrast to childhood leukemia, no pooled analyses of childhood brain tumors and exposure to extremely low-frequency magnetic fields (ELF-MFs) have been conducted. The authors carried out a pooled analysis based on primary data (1960–2001) from 10 studies of ELF-MF exposure and childhood brain tumors to assess whether the combined results, adjusted for potential confounding, indicated an association. The odds ratios for childhood brain tumors in ELF-MF exposure categories of 0.1–<0.2 μT, 0.2–<0.4 μT, and ≥0.4 μT were 0.95 (95% confidence interval: 0.65, 1.41), 0.70 (95% CI: 0.40, 1.22), and 1.1…

0329 Occupational exposure to metals and welding fumes, and risk of glioma in the interocc study

Background Brain tumouraetiology is poorly understood. Based on their ability to pass through the blood-brain barrier, it has been hypothesised that exposure to metals may increase the risk of brain cancer. Results from the few epidemiological studies on this issue are inconsistent. Methods We investigated the relationship between glioma risk and occupational exposure to five metals - lead, cadmium, nickel, chromium and iron- as well as to welding fumes, using data from the seven-country INTEROCC study. A total of 1800 incident glioma cases and 5160 controls aged 30–69 years were included in the analysis. Lifetime occupational exposure to the agents was assessed using the INTEROCC JEM, a mo…

Leukemia and Non-Hodgkin's Lymphoma in Childhood and Exposure to Pesticides: Results of a Register-based Case-Control Study in Germany

Previous studies have suggested an association between exposure to pesticides and different types of childhood cancer. This paper presents results from a population-based case-control interview study of parents of children less than 15 years of age, which was conducted in the states of West Germany from 1993 to 1997. Cases were 1,184 children with leukemia, 234 with non-Hodgkin's lymphoma, and 940 with a solid tumor; 2,588 controls were also included. Parental occupational exposures were found to be related to childhood cancer regardless of the time period of exposure and the type of cancer. This finding might partially be explained by different recall of past exposures by the parents of ca…

Location of Gliomas in Relation to Mobile Telephone Use: A Case-Case and Case-Specular Analysis

The energy absorbed from the radio-frequency fields of mobile telephones depends strongly on distance from the source. The authors' objective in this study was to evaluate whether gliomas occur preferentially in the areas of the brain having the highest radio-frequency exposure. The authors used 2 approaches: In a case-case analysis, tumor locations were compared with varying exposure levels; in a case-specular analysis, a hypothetical reference location was assigned for each glioma, and the distances from the actual and specular locations to the handset were compared. The study included 888 gliomas from 7 European countries (2000-2004), with tumor midpoints defined on a 3-dimensional grid …

Residential magnetic fields as a risk factor for childhood acute leukaemia: Results from a German population-based case-control study

Our objective was to investigate whether exposure to residential power-frequency (50 Hz) magnetic fields above 0.2 μT increases a child's risk of leukaemia and to confirm or reject a finding from a previous German study on this topic, which reported increased leukaemia risk with exposure to stronger magnetic fields during the night. A population-based case-control study was used, covering the whole of the former West Germany. Residential magnetic fields were measured over 24 hr for 514 children with acute leukaemia identified by the German Childhood Cancer Registry and 1,301 control children taken from population registration files. Magnetic fields above 0.2 μT were relatively rare in Germa…

Childhood cancer and residential radon exposure - results of a population-based case-control study in Lower Saxony (Germany)

A population-based case-control study on risk factors for childhood malignancies was used to investigate a previously reported association between elevated indoor radon concentrations and childhood cancer, with special regard to leukaemia. The patients were all children suffering from leukaemia and common solid tumours (nephroblastoma, neuroblastoma, rhabdomyosarcoma, central nervous system (CNS) tumours) diagnosed between July 1988 and June 1993 in Lower Saxony (Germany) and aged less than 15 years. Two population-based control groups were matched by age and gender to the leukaemia patients. Long-term (1 year) radon measurements were performed in those homes where the children had been liv…

Retrospektive Bestimmung der elektromagnetischen Exposition durch analoge Rundfunksender im Rahmen von KiSS

Im Rahmen einer epidemiologischen Fall-Kontroll-Studie zur Untersuchung eines möglichen Zusammenhangs zwischen der Häufigkeit kindlicher Leukämien und elektromagnetischer Strahlung (,,KiSS&quot; &amp;ndash; &lt;b&gt;Ki&lt;/b&gt;ndliche Leukämien und Expositionen in der Umgebung von hochfrequenten &lt;b&gt;S&lt;/b&gt;ende&lt;b&gt;s&lt;/b&gt;tationen) soll die Exposition durch leistungsstarke analoge Rundfunksender retrospektiv (Zeitraum 1982&amp;ndash;2003) quantifiziert werden. Die zu betrachtenden Sendernetze für AM-Hörfunk, FM-Hörfunk und analoges Fernsehen unterscheiden sich nicht nur hinsichtlich der Modulationsart und der von den Einzelsendern abgestrahlten Leistung, sondern auch in de…

Extremely low-frequency magnetic fields and survival from childhood acute lymphoblastic leukemia: an international follow-up study

A previous US study reported poorer survival in children with acute lymphoblastic leukemia (ALL) exposed to extremely low-frequency magnetic fields (ELF–MF) above 0.3 μT, but based on small numbers. Data from 3073 cases of childhood ALL were pooled from prospective studies conducted in Canada, Denmark, Germany, Japan, UK and US to determine death or relapse up to 10 years from diagnosis. Adjusting for known prognostic factors, we calculated hazard ratios (HRs) and 95% confidence intervals (CI) for overall survival and event-free survival for ELF–MF exposure categories and by 0.1 μT increases. The HRs by 0.1 μT increases were 1.00 (CI, 0.93–1.07) for event-free survival analysis and 1.04 (CI…

Atopic disease and childhood acute lymphoblastic leukemia

Our objective was to test the hypothesis that the risk of childhood leukemia is associated with allergies or a family history of allergy. We used a German population-based case-control study with self-reported information on allergies of the children and their first-degree relatives. Our study included a total of 1,130 cases of acute lymphoblastic leukemia (ALL), 164 cases of acute myeloid leukemia (AML) and 2,957 controls. A major finding of our study is that hay fever, neurodermatitis and contact eczema are underrepresented within the group of children with ALL, with respective odds ratios (OR) of 0.45 (95% confidence interval [CI] 0.31-0.66) for hay fever, of 0.49 (CI 0.34-0.71) for neur…

Kindliche Leukämien und EMF-Expositionen in der Umgebung hochfrequenter Sendestationen (KiSS) &ndash; Fragestellung und Studienbeschreibung

Abstract. Im Rahmen einer Fall-Kontroll-Studie wird untersucht, ob es einen Zusammenhang zwischen dem Leukämierisiko bei Kindern und der Exposition gegenüber elektromagnetischen Feldern in der Umgebung leistungsstarker Sendestationen von Rundfunk und Fernsehen gibt. Bislang wurden fünf Studien im Umkreis von Rundfunksendeanlagen durchgeführt. Deren Aussagekraft ist jedoch durch eine grobe Expositionsabschätzung und ihren ökologischen Studienansatz ohne individuelle Expositionsbestimmung limitiert. Wesentliches Element der hier vorgestellten Studie ist dagegen eine individuelle Expositionsabschätzung, die zum einen auf der Geocodierung von Wohnadressen und Expositionspunktquellen und zum and…

Home pesticide exposures and risk of childhood leukemia: Findings from the childhood leukemia international consortium

Some previous studies have suggested that home pesticide exposure before birth and during a child's early years may increase the risk of childhood leukemia. To further investigate this, we pooled individual level data from 12 case-control studies in the Childhood Leukemia International Consortium. Exposure data were harmonized into compatible formats. Pooled analyses were undertaken using multivariable unconditional logistic regression. The odds ratio (ORs) for acute lymphoblastic leukemia (ALL) associated with any pesticide exposure shortly before conception, during pregnancy and after birth were 1.39 (95% confidence interval [CI]: 1.25, 1.55) (using 2,785 cases and 3,635 controls), 1.43 (…

Fetal growth and childhood acute lymphoblastic leukemia: Findings from the childhood leukemia international consortium

Positive associations have been reported between measures of accelerated fetal growth and risk of childhood acute lymphoblastic leukemia (ALL). We investigated this association by pooling individual-level data from 12 case-control studies participating in the Childhood Leukemia International Consortium. Two measures of fetal growth – weight-for-gestational-age and proportion of optimal birth weight (POBW) – were analysed. Study-specific odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, and combined in fixed effects meta-analyses. Pooled analyses of all data were also undertaken using multivariable logistic regression. Subgroup analy…

Electromagnetic Fields and Childhood Leukemia: Pooled Analyses of Two German Population-Based Case-Control Studies

From 1992 to 1995 we conducted a population-based case-control study on residential magnetic fields and childhood leukemia in Lower Saxony, a region in northwestern Germany with 7.4 million inhabitants.1,2 Because of the rural character of this area, we detected elevated magnetic fields in only 1.5% of all dwellings. We therefore expanded the EMF-measurements to an ongoing case-control study on childhood leukemia in the capital of Germany, Berlin. We applied the same methods of exposure assessment, intending to pool the data of the two studies and to calculate combined risk estimates.3

Risk factors for pediatric tumors of the central nervous system: Results from a German population-based case-control study

From 1993 to 1997 we conducted two population-based case-control studies on childhood cancer and a variety of potential risk factors in Germany. One case group involved children under the age of 15 years having a tumor of the central nervous system (CNS).For both studies, one conducted in the northwestern area of Germany, the other covering the whole of West Germany, incident cases were identified from the nationwide German Childhood Cancer Registry, and controls were randomly selected from complete population registration files.In total 466 pediatric CNS tumor cases and 2,458 controls were available for analyses. We observed only few positive associations, namely, between CNS tumors and lo…

Survival from childhood acute lymphoblastic leukaemia in West Germany: Does socio-demographic background matter?

Sex, age, immunophenotype and white blood cell count at diagnosis are well accepted predictors of survival from acute lymphoblastic leukaemia (ALL) in children. Less is known about the relationship between socio-economic determinants and survival from paediatric ALL, studied here for the first time in German children.ALL cases were diagnosed between 1992 and 1994 and their parents interviewed during a previous nationwide case-control study. Children were followed-up for 10 years after diagnosis by the German Childhood Cancer Registry. Cox proportional hazards models estimating hazard ratios (HRs) were calculated to assess the impact of selected socio-demographic characteristics on overall a…

The Porto European Cancer Research Summit 2021.

Key stakeholders from the cancer research continuum met in May 2021 at the European Cancer Research Summit in Porto to discuss priorities and specific action points required for the successful implementation of the European Cancer Mission and Europe's Beating Cancer Plan (EBCP). Speakers presented a unified view about the need to establish high‐quality, networked infrastructures to decrease cancer incidence, increase the cure rate, improve patient's survival and quality of life, and deal with research and care inequalities across the European Union (EU). These infrastructures, featuring Comprehensive Cancer Centres (CCCs) as key components, will integrate care, prevention and research acros…

Epidemiology of pediatric tumors of the central nervous system.

Tumors of the CNS are the second most frequent malignancy in childhood and the most common of the solid tumors. An increase in CNS tumor rates during the past decades has been observed in a number of countries. One possibility is that improvements in diagnostics of CNS tumors contributed to the increasing trend. Another concern is that changes in environmental exposures may be responsible for the increasing incidence rates and a number of epidemiologic studies investigated factors like exposure to ionizing radiation, electromagnetic fields, or pesticides. In addition, prenatal exposures, for example from maternal diet, or the role of infectious agents were of particular interest. In this re…

Association of childhood leukaemia with factors related to the immune system

The childhood peak of common acute lymphoblastic leukaemia has been proposed as being a rare response to delayed exposure to a common infection. In this context, factors related to the child’s immune system are of special interest. Information on such factors was obtained in a recent German case-control study comprising more than 1000 children with acute leukaemia. Neither being the first-born child, nor a short duration of breastfeeding, indicators of a deficit in viral contacts during infancy or the number of infectious diseases, were significant risk factors. We observed a strong association with fewer routine immunizations with a 3.2-fold increase for those children getting less than fo…

The Authors Respond to Olshan and Daniels

Mobile phone use and exposures in children.

The main difference concerning the use of mobile phones (MPs) between today's children and adults is the longer lifetime exposure of children when they grow older, due to starting to use MPs at an early age. Additionally, recent trends lead to a higher frequency of use among children, including higher popularity of MPs and features specifically designed to attract children. The prevalence of MP users is already very high and reaches >90% among adolescents in some countries. In a German study, 6% of 9-10 years old children used a MP for making calls daily; 35% owned their own MP. For children, MPs are dominant sources of radio wave exposures and relevant sources of extremely low frequency ma…

Bone marrow punctures and pain

Abstract We prospectively analysed pain in 263 patients induced by a frequent diagnostic procedure for oncologists, specifically the bone marrow puncture. Substantial pain (5 and more out of 10 on a numerical rating scale) was reported by 30.4% of patients, but physicians did not realize this procedure-related pain of patients in more than 50% of such punctures. The necessity for improved analgesia is emphasized by the fact, that at least 50% of patients experiencing substantial pain wished to receive concomitant medication in future punctures. Duration of the procedure was identified as sole independent predictive factor for patients’ pain intensity, while patients’ characteristics like ge…

Association of childhood cancer with factors related to pregnancy and birth

It has been hypothesized that risk factors of childhood cancers may already operate during the prenatal and neonatal period. Results of previous epidemiological studies have been inconsistent.During 1992-1997 a large case-control study on childhood cancers and a variety of potential risk factors was conducted in Germany. Cases were ascertained by the German Childhood Cancer Registry. Each case was matched to a population-based control of the same age and gender, sampled from the district where the case lived at the date of diagnosis. For the analyses, 2358 cases and 2588 controls were available.Risk of childhood acute leukaemia increased with maternal ageor =20 years at time of delivery (od…

Childhood cancer incidence patterns by race, sex and age for 2000-2006: A report from the South African National Cancer Registry

Higher childhood cancer incidence rates are generally reported for high income countries although high quality information on descriptive patterns of childhood cancer incidence for low or middle income countries is limited, particularly in Sub-Saharan Africa. There is a need to quantify global differences by cancer types, and to investigate whether they reflect true incidence differences or can be attributed to under-diagnosis or under-reporting. For the first time, we describe childhood cancer data reported to the pathology report-based National Cancer Registry of South Africa in 2000-2006 and compare our results to incidence data from Germany, a high income country. The overall age-standa…

Parental occupational pesticide exposure and the risk of childhood leukemia in the offspring: Findings from the childhood leukemia international consortium

Maternal occupational pesticide exposure during pregnancy and/or paternal occupational pesticide exposure around conception have been suggested to increase risk of leukemia in the offspring. With a view to providing insight in this area we pooled individual level data from 13 case-control studies participating in the Childhood Leukemia International Consortium (CLIC). Occupational data were harmonized to a compatible format. Pooled individual analyses were undertaken using unconditional logistic regression. Using exposure data from mothers of 8,236 cases, and 14,850 controls, and from fathers of 8,169 cases and 14,201 controls the odds ratio (OR) for maternal exposure during pregnancy and t…

A discussion of potential exposure metrics for use in epidemiological studies on human exposure to radiowaves from mobile phone base stations

There is currently a high level of concern in many countries that exposure to radiowaves from mobile phone base stations may be hazardous to health. When investigating such suggested risks, epidemiologists need to define an exposure metric that can reliably discriminate between exposed and unexposed groups of people. We conducted a feasibility study to investigate if either short-term measurements of electric field strength, calculations of electric field strength, or distance from nearby mobile phone base stations could be used to develop a metric reflecting an individual's exposure to radiowaves. With electric field strengths in the range of 0.012-0.343 V/m, radiowaves from mobile phone b…

Radiofrequency electromagnetic fields emitted from base stations of DECT cordless phones and the risk of glioma and meningioma (Interphone Study Group, Germany)

The objective of this study was to test the hypothesis that exposure to continuous low-level radiofrequency electromagnetic fields (RF EMFs) increases the risk of glioma and meningioma. Participants in a population-based case-control study in Germany on the risk of brain tumors in relation to cellular phone use were 747 incident brain tumor cases between the ages of 30 and 69 years and 1494 matched controls. The exposure measure of this analysis was the location of a base station of a DECT (Digital Enhanced Cordless Telecommunications) cordless phone close to the bed, which was used as a proxy for continuous low-level exposure to RF EMFs during the night. Estimated odds ratios were 0.82 (95…

Bias in Studies of Parental Self-reported Occupational Exposure and Childhood Cancer

Several case-control studies have demonstrated positive associations between parental occupational exposures and childhood cancer. However, an overestimation of risk estimates due to recall bias is of concern. The magnitude and nature of this bias were explored using data from a German case-control study on childhood leukemia conducted between 1992 and 1997. A moderate overreporting of occupational exposures by fathers was observed, particularly for the prenatal period. Overreporting was most apparent when the time between exposure and interview was short. It was also found that job titles were no satisfactory substitute for information on specific occupational exposures. The results of thi…

Non-response bias as a likely cause of the association between young maternal age at the time of delivery and the risk of cancer in the offspring.

Some epidemiological studies have shown an association between young maternal age at the time of delivery and risk of cancer in the offspring. In a recent German case-control study, there was a twofold increase in the leukaemia risk for children whose mothers were aged < 20 years at the time of delivery. As the prevalence of younger mothers among control families was particularly low, data on maternal age distributions for the general population of Germany were obtained in order to examine the representativeness of the control sample. Despite the excellent sampling frame based on data from complete and up-to-date population registries and a satisfactory response rate among controls ( approx…

Assessment of radiofrequency exposure from cellular telephone daily use in an epidemiological study: German Validation study of the international case-control study of cancers of the brain--INTERPHONE-Study.

The objective of the study is to validate self-reported cellular phone use information by comparing it with the cumulative emitted power and duration of calls measured by software-modified cellular phones (SMP). The information was obtained using a questionnaire developed for the international case-control study on the risk of the use of mobile phones in tumours of the brain or salivary gland (INTERPHONE-study).The study was conducted in Bielefeld, Germany. Volunteers were asked to use SMPs instead of their own cellular phones for a period of 1 month. The SMP recorded the power emitted by the mobile phone handset during each base station contact. Information on cellular phone use for the sa…

European code against cancer 4th edition: 12 ways to reduce your cancer risk

AbstractThis overview describes the principles of the 4th edition of the European Code against Cancer and provides an introduction to the 12 recommendations to reduce cancer risk. Among the 504.6 million inhabitants of the member states of the European Union (EU28), there are annually 2.64 million new cancer cases and 1.28 million deaths from cancer. It is estimated that this cancer burden could be reduced by up to one half if scientific knowledge on causes of cancer could be translated into successful prevention. The Code is a preventive tool aimed to reduce the cancer burden by informing people how to avoid or reduce carcinogenic exposures, adopt behaviours to reduce the cancer risk, or t…

Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields.

Abstract Background The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF) in Germany. Methods A set of criteria was developed to evaluate the feasibility of such a cohort study. The criteria aimed at conditions of exposure and exposure assessment (level, duration, preferably on an individual basis), the possibility to assemble a cohort and the feasibility of ascertaining various disease endpoints. Results Twenty occupational settings with workers potentially exposed to RF-EMF and, in addition, a cohort of amateur radio operators were considered. Based on expert ratings, l…

Risk factors for neuroblastoma at different stages of disease. Results from a population-based case-control study in Germany

Neuroblastoma is one of the childhood cancers included in two recent population-based case-control studies in West Germany. Altogether, 183 children under the age of 8 with neuroblastoma diagnosed in 1988-1994 and 1785 control children sampled from population registration files participated. Information on potential risk factors was obtained from the children's parents by a self-administered questionnaire and subsequent telephone interview. We observed positive associations with the use of oral contraceptives or other sex hormones during pregnancy (particularly with male offspring), a shorter gestational duration, lower birth weight, and maternal alcohol consumption during pregnancy. While …

Population-based epidemiologic data on brain tumors in German children.

BACKGROUND Brain tumors are the most common disease group of solid tumors in childhood, and children with brain tumors have a relatively poor survival rate. Epidemiologic data from a population-based cancer registry provide the necessary information to obtain a full picture of the frequency of this disease, which is a great challenge in pediatric oncology. METHODS The German Childhood Cancer Registry (GCCR) is a population-based registry. The level of completeness of patient registration is 95%, but it is somewhat lower for patients with brain tumors. More than 300 children with newly diagnosed brain tumors are reported every year. Analyses of GCCR data are performed according to the Intern…

Environmental risk factors for sporadic acoustic neuroma (Interphone Study Group, Germany)

The only known risk factor for sporadic acoustic neuroma is high-dose ionising radiation. Environmental exposures, such as radiofrequency electromagnetic fields and noise are under discussion, as well as an association with allergic diseases. We performed a population-based case-control study in Germany investigating these risk factors in 97 cases with acoustic neuroma, aged 30 to 69 years, and in 194 matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated in multiple logistic regression models. Increased risks were found for exposure to persistent noise (OR=2.31; 95% CI 1.15-4.66), and for hay fever (OR=2.20; 95% CI 1.09-4.45), but not for ionising radiation …

Feasibility of future epidemiological studies on possible health effects of mobile phone base stations.

The increasing deployment of mobile communication base stations led to an increasing demand for epidemiological studies on possible health effects of radio frequency emissions. The methodological challenges of such studies have been critically evaluated by a panel of scientists in the fields of radiofrequency engineering/dosimetry and epidemiology. Strengths and weaknesses of previous studies have been identified. Dosimetric concepts and crucial aspects in exposure assessment were evaluated in terms of epidemiological studies on different types of outcomes. We conclude that in principle base station epidemiological studies are feasible. However, the exposure contributions from all relevant …

Family circumstances and survival from childhood acute lymphoblastic leukaemia in West Germany

Little is known about the relationship between family characteristics and survival from childhood acute lymphoblastic leukaemia (ALL), which we studied for the first time in German children.ALL cases were diagnosed between 1992 and 1994 and information on family characteristics was collected during a previously conducted nationwide case-control study. Children were followed for 10 years after diagnosis, as few disease-related events occur afterwards. Cox proportional hazards models estimating hazard ratios (HR) were calculated using overall as well as event-free survival methods.Second born children showed statistically significant better survival compared to first or later born children, w…