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Background: The aetiology of neuroblastic tumours is unclear with both genetic and environmental factors implicated. The possibility that an infectious agent may be involved has been suggested. 'Temporal clustering' occurs if cases display an irregular temporal distribution and may indicate the involvement of an agent that exhibits epidemicity. We tested for the presence and nature of temporal clustering using population-based data from northern England. Methods: We extracted all cases of neuroblastic tumours diagnosed in children and young adults aged 0-24 years during 1968-2011 from the Northern Region Young Persons' Malignant Disease Registry. This is a population-based registry, covering a population of approximately 900,000 young persons, and includes all cases resident in northern England at the time of diagnosis. Tests for temporal clustering were applied using a modified version of the Potthoff-Whittinghill method. Estimates of extra-Poisson variation (β̂) and standard errors (SEs) were obtained. Results: 227 cases of neuroblastic tumours were diagnosed during the study period. All the analyses between fortnights and between months found significant extra-Poisson variation, with β̂ =0.846 (SE = 0.310, P = 0.004) for the analysis between fortnights within months. Restricting the analyses to the 76 cases diagnosed at ages less than 18 months showed significant extra-Poisson variation between fortnights within months (β̂ =1.532, SE = 0.866, P = 0.038), but not between months. In contrast, analyses of cases aged 18 months to 24 years showed significant extra-Poisson variation between quarters within years, as well as over shorter timescales. Conclusions: Transient environmental agents may be involved in the aetiology of neuroblastic tumours. The initiating factor might be a geographically-widespread agent that occurs in 'mini-epidemics'. [ABSTRACT FROM AUTHOR]

Background: The aetiology of bone cancers is poorly understood. This study examined geographical patterning in incidence of primary bone cancers diagnosed in 0-49 year olds in Great Britain during 1980-2005 to provide information on factors linked with disease development. We investigated putative associations with deprivation and population density. Methods: Data on osteosarcoma and Ewing sarcoma were obtained from national population-based registries. Negative binomial regression was used to examine the relationship between incidence rates and the Townsend deprivation score (and its component variables) and small-area population density. Results: The study analyzed 2566 osteosarcoma and 1650 Ewing sarcoma cases. For females with osteosarcoma, statistically significant decreased risk was associated with higher levels of deprivation (relative risk [RR] per unit increase in deprivation score = 0.969; 95% confidence interval [CI] 0.946-0.993). For all Ewing sarcoma combined, statistically significant decreased risk was associated with greater area-level population density and higher levels of non-car ownership (RR per person per hectare increase = 0.984; 95% CI 0.976-0.993, RR per 1% increase in non-car ownership = 0.994; 95% CI 0.991-0.998). Conclusions: Higher incidence of osteosarcoma was observed for females in areas with lower deprivation levels indicating increased risk is linked to some aspect of affluent living. Higher incidence of Ewing sarcoma occurred in areas of low population density and where more people owned cars, both characteristic of rural environments. The study adds substantially to evidence associating Ewing sarcoma risk with rural environmental exposures. Putative risk factors include agricultural exposures, such as pesticides and zoonotic agents [ABSTRACT FROM AUTHOR]

Background: There is a paucity of recent epidemiological data on bone cancers. The aim of this study was to describe incidence and survival patterns for bone cancers diagnosed during 1981 - 2002. Methods: Cases aged 0 - 39 years (236 osteosarcomas, 166 Ewing sarcomas and 73 chondrosarcomas) were analysed using Poisson and Cox regressions. Results: Incidence rates (per million persons per year) for osteosarcoma were 2.5 at age 0 - 14 years; 4.5 at age 15 - 29 years and 1.0 at age 30 - 39 years. Similarly, for Ewing sarcoma the incidence rates were 2.2; 2.9; 0.4 and for chondrosarcoma rates were 0.1; 1.2; 1.8 respectively. Incidence of osteosarcoma increased at an average annual rate of 2.5% (95% CI 0.4 - 4.7; P = 0.02), but there was no change in incidence of Ewing sarcoma or chondrosarcoma. There was a marginally statistically significant improvement in survival for Ewing sarcoma (hazard ratio (HR) per annum = 0.97; 95% CI 0.94 - 1.00; P = 0.06), although patients aged 15 - 39 years (n = 93) had worse overall survival than those aged 0 - 14 (n = 73; HR = 1.46; 95% CI 0.98 - 2.17; P = 0.06). There was no significant improvement in osteosarcoma survival (HR per annum = 0.98; 95% CI 0.95 - 1.01; P = 0.18). Conclusions: Reasons for poorer survival in Ewing sarcoma patients aged 15 - 39 years and failure to significantly improve survival for osteosarcoma patients requires further investigation. [ABSTRACT FROM AUTHOR]

Background: The aetiology of type 1 diabetes in children is uncertain. A number of recent studies have suggested an infectious aetiology. It has been postulated that an infectious agent may be involved. Support for this hypothesis may be provided by a finding of space-time clustering. The aims of this study were: (i) to determine whether there was space-time clustering in cases of childhood diabetes from north-east England; and to test for differences in space-time clustering: (ii) due to age at diagnosis; (iii) between the sexes and (iv) between levels of residential population density. Methods: We studied incidence of type 1 diabetes diagnosed in children aged 0-14 years and diagnosed during the period 1990-2007. All cases were resident in a defined geographical region of north-east England (Northumberland, Newcastle upon Tyne and North Tyneside). We applied a second-order procedure based on K-functions to test for global clustering. Locations were residential addresses at time of diagnosis. Tests were repeated using nearest neighbour thresholds to allow for variable population density, providing the primary result for each analysis. Differences between sexes and between levels of population density were assessed. Results: We analysed 457 cases of type 1 diabetes. Overall, there was marginally significant evidence of global space-time clustering (P = 0.089). There was statistically significant clustering amongst pairs of cases that contained at least one female (P = 0.017), but not amongst pairs of cases that contained at least one male (P = 0.190). Furthermore, there was significant clustering amongst pairs of cases that contained at least one from a more densely populated area (P = 0.044), but not amongst pairs of cases that contained at least one from a less densely populated area (P = 0.226). Conclusion: Although the analyses have only found marginally significant evidence of global spacetime clustering for cases of type 1 diabetes diagnosed in north-east England, there were two notable findings. First, there was evidence of clustering amongst females and secondly clustering was confined to cases from more densely populated areas. These findings are consistent with a possible aetiological involvement of an infectious agent. [ABSTRACT FROM AUTHOR]

Background: This study examined sex-specific patterns and temporal trends in the incidence of solid tumours in the Northern Region of England from 1968 to 2005. This updates earlier analyses from the region where sex was not considered in depth. Sex-specific analyses were carried out to determine whether sex differences might provide clues to aetiology. Methods: Details of 3576 cases, aged 0-24 years, were obtained from a specialist population-based cancer registry. There were 1843 males (886 aged 0-14 years and 957 aged 15-24 years) and 1733 females (791 aged 0-14 years and 942 aged 15-24 years). Age-standardized incidence rates (per million population) were calculated. Linear regression was used to analyze temporal trends in incidence and annual percentage changes were estimated. Analyses were stratified by sex and by age-group. Results: There were marked differences in incidence patterns and trends between males and females and also between age-groups. For males central nervous system (CNS) tumours formed the largest proportion of under- 15 cases and germ cell tumours was the largest group in the 15-24's, whilst for females CNS tumours dominated in the under-15's and carcinomas in the older group. For 0-14 year olds there were male-specific increases in the incidence of rhabdomyosarcoma (2.4% per annum; 95% CI: 0.2%-4.5%) and non-melanotic skin cancer (9.6%; 95% CI: 0.0%-19.2%) and female-specific increases for sympathetic nervous system tumours (2.2%; 95% CI: 0.4%-3.9%), gonadal germ cell tumours (8.6%; 95% CI: 4.3%-12.9%) and non-gonadal germ cell tumours (5.4%; 95% CI: 2.8%-7.9%). For 15-24 year olds, there were male-specific increases in gonadal germ cell tumours (1.9%; 95% CI: 0.3%-3.4%), non-gonadal germ cell tumours (4.4%; 95% CI: 1.1%-7.7%) and non-melanotic skin cancer (4.7%; 95% CI: 0.5%-8.9%) and female-specific increases for osteosarcoma (3.5%; 95% CI: 0.5%-6.5%), thyroid cancer (2.8%; 95% CI: 0.1%-5.6%) and melanoma (4.6%; 95% CI: 2.2%-7.1%). Conclusion: This study has highlighted notable differences between the sexes in incidence patterns and trends for solid tumours. Some of these sex-specific differences could have been obscured if males and females had been analysed together. Furthermore, they suggest aetiological differences or differential susceptibility to environmental factors between males and females. [ABSTRACT FROM AUTHOR]

Background: We specifically tested the aetiological hypothesis that a factor influencing geographical or temporal heterogeneity of childhood central nervous system (CNS) tumour incidence was related to exposure to a transient environmental agent.Methods: Information was extracted on individuals aged 0-14 years, diagnosed with a CNS tumour between the 1st January 1974 and 31st December 2006 from the Yorkshire Specialist Register of Cancer in Children and Young People. Ordnance Survey eight-digit grid references were allocated to each case with respect to addresses at the time of birth and the time of diagnosis, locating each address to within 0.1 km. The following diagnostic groups were specified a priori for analysis: ependymoma; astrocytoma; primitive neuroectodermal tumours (PNETs); other gliomas; total CNS tumours. We applied the K-function method for testing global space-time clustering using fixed geographical distance thresholds. Tests were repeated using variable nearest neighbour (NN) thresholds.Results: There was statistically significant global space-time clustering for PNETs only, based on time and place of diagnosis (P = 0.03 and 0.01 using the fixed geographical distance and the variable NN threshold versions of the K-function method respectively).Conclusions: There was some evidence for a transient environmental component to the aetiology of PNETs. However, a possible role for chance cannot be excluded. [ABSTRACT FROM AUTHOR]

Background: There is a paucity of recent epidemiological data on bone cancers. The aim of this study was to describe incidence and survival patterns for bone cancers diagnosed during 1981 - 2002., Methods: Cases aged 0 - 39 years (236 osteosarcomas, 166 Ewing sarcomas and 73 chondrosarcomas) were analysed using Poisson and Cox regressions., Results: Incidence rates (per million persons per year) for osteosarcoma were 2.5 at age 0 - 14 years; 4.5 at age 15 - 29 years and 1.0 at age 30 - 39 years. Similarly, for Ewing sarcoma the incidence rates were 2.2; 2.9; 0.4 and for chondrosarcoma rates were 0.1; 1.2; 1.8 respectively. Incidence of osteosarcoma increased at an average annual rate of 2.5% (95% CI 0.4 - 4.7; P = 0.02), but there was no change in incidence of Ewing sarcoma or chondrosarcoma. There was a marginally statistically significant improvement in survival for Ewing sarcoma (hazard ratio (HR) per annum = 0.97; 95% CI 0.94 - 1.00; P = 0.06), although patients aged 15 - 39 years (n = 93) had worse overall survival than those aged 0 - 14 (n = 73; HR = 1.46; 95% CI 0.98 - 2.17; P = 0.06). There was no significant improvement in osteosarcoma survival (HR per annum = 0.98; 95% CI 0.95 - 1.01; P = 0.18)., Conclusions: Reasons for poorer survival in Ewing sarcoma patients aged 15 - 39 years and failure to significantly improve survival for osteosarcoma patients requires further investigation.