Childhood cancer and ethnic group in Britain: a United Kingdom children's Cancer Study Group (UKCCSG) study

Childhood leukaemia incidence and trends in a Middle Eastern country during 1980-2014: a population-based study

BACKGROUND

This retrospective cohort study examines the trends in childhood leukaemia age-standardized incidence rates (ASIRs) (per million person-years) using cases which were diagnosed at age 0-19 years from 1980 to 2014 and recorded in the Kuwait Cancer Control Center (KCCC) registry.

METHODS

Childhood leukaemia age-specific incidence rates overall and by sub-cohorts defined by age (0-4, 5-9, 10-14, and 15-19 years), sex (male, female) and nationality (Kuwaiti, non-Kuwaiti) were computed and age-standardized. Joinpoint regression models were used to evaluate trends in childhood leukaemia ASIRs. Average annual percent change (AAPC) and its 95% confidence interval (CI) were used to interpret the observed trends.

RESULTS

During the study period, 1077 childhood leukaemia cases of 32.3 million person-years were diagnosed. From 1980 to 2014, the average annual childhood leukaemia ASIR was 53.1 (95% CI 20.9, 85.2). Overall childhood leukaemia ASIRs significantly decreased on average by 6.8% per year (AAPC =  -6.8; 95% CI -12.1, -1.1; p = 0.02) from 1980 to 1993, but a marginally significant increase in ASIRs from 1993 to 2014 was recorded (AAPC = 2.5; 95% CI -0.5, 5.5; p = 0.10). During the entire period, childhood leukaemia ASIRs trends significantly (p < 0.05) increased among 6 of 16 sub-cohorts, which was more pronounced among females and 10-14-year-old children.

CONCLUSIONS

Overall, ASIRs significantly increased from 1993 to 2014, which specifically seems to be driven by an increase in ASIRs among females and 10-14 -year-old children. These increasing trends underscore the potential involvement of a range of exposures. Future studies on unravelling such factors may help develop preventive measures to minimize childhood leukaemia risk in this and similar settings in the region.

PLK1 contributes to autophagy by regulating MYC stabilization in osteosarcoma cells

Background

PLK1, a typical PLK protein, is the main driver of cancer cell growth and proliferation. It is an inhibitor of the protein kinases that is currently being investigated in clinical studies. It is often used as a tumor marker, as high PLK1 expression correlates with poor prognosis in cancer. Overexpression of MYC is a hallmark of many human cancers. MYC modulates the transcription of thousands of genes that required to coordinate a series of cellular processes, including those essential for growth, proliferation, differentiation, self-renewal and apoptosis. To date, functions of PLK1 and MYC on tumor are mostly studied in separate researches, and studies on their mutual crosstalk are lacking.

Purpose

To investigate the mechanism of PLK1 and MYC in regulating progress of osteosarcoma.

Methods

Protein level was examined using Western blot. Animal experiments were performed with female FOX CHASE severe combined immunodeficient mice. Mice were randomly divided into experimental or control groups.

Results

PLK1 or MYC promoted the proliferation of osteosarcoma cells through the autophagy pathway. PLK1 contributed to MYC protein stabilization. PLK1 inhibition enhanced MYC degradation in osteosarcoma cells. PLK1 inhibition led to a marked decline in MYC protein abundance. The representative MYC target genes were deregulated by PLK1 inhibitors. BI2536 treatment caused a significant delay in xenograft tumor growth in mice injected with U-2 OS cells subcutaneously, with lower mean tumor weight compared to the control group.

Conclusion

PLK1 is crucial for MYC stabilization. It promotes cell proliferation by autophagy pathway in osteosarcoma cells. Data validate PLK1 as a potential therapeutic target in osteosarcoma caused by MYC-amplified.

Paediatric Peripheral Primitive Neuroectodermal Tumour - A Clinico-Pathological Study from Southern India

Introduction

Primitive Neuroectodermal Tumour (PNET)/Ewing Sarcomas (ES) are aggressive childhood malignancies with neuroectodermal differentiation.

Aim

To study the clinical presentation, morphology, Immun-ohistochemistry (IHC), management and outcome of all the cases of paediatric pPNET/ES reported in our tertiary care centre over a period of six years.

Materials and Methods

This was a retrospective study conducted at Sri Ramachandra Medical College and Research Institute, Chennai, India. All biopsy proven cases of peripheral PNET/ES, in patients less than 18 years of age for a period of six years were included in this study. The corresponding clinical details regarding initial presentation, treatment and follow up were retrieved from the case files and analysed. Survival rate was calculated and Kaplan-Meier survival curve was plotted.

Results

We describe eleven cases of paediatric peripheral PNET/ES. The mean age at presentation was 94.08 (±58.27) months with a male/female ratio of 1.2:1. About 27.3% cases, all male with a mean age of 140 months at presentation, had distant metastasis during initial diagnosis. Biopsy showed small round blue cell morphology on light microscopy. IHC revealed strong membranous staining for CD99 in all cases. All children were treated with neo-adjuvant chemotherapy and then surgery, followed by radiotherapy if indicated. The cases were followed up for a mean duration of 20.82 months (ranging from one to 66 months). Nine children are doing well on follow up (81.8% survival rate). Two cases with metastasis at initial presentation died. Patients with metastatic disease exhibited a mean duration of survival of 9.66 (±7.24) months and those with localized disease exhibited a mean duration of survival of 25 (±22.88) months.

Conclusion

Metastasis at diagnosis is the single most important factor affecting prognosis. This was reflected in the present study where cases with metastasis exhibited a short mean duration of survival when compared to localized disease. It is likely that many cases of PNET/ES were not accurately identified in the past as IHC plays a vital role in the diagnosis of these small round blue cell tumours. IHC in adjunct with molecular studies has improved diagnostic accuracy. Multidisciplinary management and good supportive care when the lesion is localized has lead to improved survival.

Childhood cancer incidence by ethnic group in England, 2001-2007: a descriptive epidemiological study

BACKGROUND

After the first year of life, cancers are the commonest cause of death in children. Incidence rates vary between ethnic groups, and recent advances in data linkage allow for a more accurate estimation of these variations. Identifying such differences may help identify potential risk or protective factors for certain childhood cancers. This study thus aims to ascertain whether such differences do indeed exist using nationwide data across seven years, as have previously been described in adult cancers.

METHODS

We obtained data for all cancer registrations for children (aged 0-14) in England from January 2001 to December 2007. Ethnicity (self-assigned) was established through record linkage to the Hospital Episodes Statistics database or cancer registry data. Cancers were classified morphologically according to the International Classification of Childhood Cancer into four groups - leukaemias; lymphomas; central nervous system; and other solid tumours. Age standardised incidence rates were estimated for each ethnic group, as well as incidence rate ratios comparing each individual ethnic group (Indian, Pakistani, Bangladeshi, Black African, Black Carribean, Chinese) to Whites, adjusting for sex, age and deprivation.

RESULTS

The majority of children in the study are UK born. Black children (RR = 1.18, 99% CI: 1.01-1.39), and amongst South Asians, Pakistani children (RR = 1.19, 99% CI: 1.02-1.39) appear to have an increased risk of all cancers. There is an increased risk of leukaemia in South Asians (RR = 1.31, 99% CI: 1.08-1.58), and of lymphoma in Black (RR = 1.72, 99% CI: 1.13-2.63) and South Asian children (RR = 1.51, 99% CI: 1.10-2.06). South Asians appear to have a decreased risk of CNS cancers (RR = 0.71, 99% CI: 0.54-0.95).

CONCLUSIONS

In the tradition of past migrant studies, such descriptive studies within ethnic minority groups permit a better understanding of disease incidence within the population, but also allow for the generation of hypotheses to begin to understand why such differences might exist. Though a major cause of mortality in this age group, childhood cancer remains a relatively rare disease; however, the methods used here have permitted the first nationwide estimation of childhood cancer by individual ethnic group.

Cancer of childhood in sub-Saharan Africa

Measurement of incidence rates of childhood cancer in Africa is difficult. The study 'Cancer of Childhood in sub Saharan Africa' brings together results from 16 population-based registries which, as members of the African Cancer Registry Network (AFCRN), have been evaluated as achieving adequate coverage of their target population. The cancers are classified according to the third revision of the International Classification of Childhood Cancer (ICCC-3) and recorded rates in Africa are compared with those in childhood populations in the UK, France, and the USA. It is clear that, in many centres, lack of adequate diagnostic and treatment facilities leads to under-diagnosis (and enumeration) of leukaemias and brain cancers. However, for several childhood cancers, incidence rates in Africa are higher than those in high-income countries. This applies to infection-related cancers such as Kaposi sarcoma, Burkitt lymphoma, Hodgkin lymphoma and hepatocellular carcinoma, and also to two common embryonal cancers - retinoblastoma and nephroblastoma. These (and other) observations are unlikely to be artefact, and are of considerable interest when considering possible aetiological factors, including ethnic differences in risk (and hence genetic/familial antecedents). The data reported are the most extensive so far available on the incidence of cancer in sub Saharan Africa, and clearly indicate the need for more resources to be devoted to cancer registration, especially in the childhood age range, as part of an overall programme to improve the availability of diagnosis and treatment of this group of cancers, many of which have-potentially-an excellent prognosis.

Editorial: Childhood Cancer in sub-Saharan Africa

Measurement of incidence rates of childhood cancer in Africa is difficult. The study 'Cancer of Childhood in sub Saharan Africa' [Stefan C, Bray F, Ferlay J, Parkin DM and Liu B (2017) Cancer of Childhood in sub-Saharan Africaecancer11(755)] brings together results from 16 population-based registries which, as members of the African Cancer Registry Network (AFCRN), have been evaluated as achieving adequate coverage of their target population. The cancers are classified according to the third revision of the International Classification of Childhood Cancer (ICCC-3) and recorded rates in Africa are compared with those in childhood populations in the UK, France, and the USA. It is clear that, in many centres, lack of adequate diagnostic and treatment facilities, leads to under-diagnosis (and enumeration) of leukaemias and brain cancers. However, for several childhood cancers, incidence rates in Africa are higher than those in high income countries. This applies to infection-related cancers such as Kaposi sarcoma, Burkitt lymphoma, Hodgkin lymphoma and hepatocellular carcinoma, and also to two common embryonal cancers-retinoblastoma and nephroblastoma. These (and other) observations are unlikely to be artefact, and are of considerable interest when considering possible aetiological factors, including ethnic differences in risk (and hence genetic/familial antecedents). The data reported are the most extensive so far available on the incidence of cancer in sub Saharan Africa, and clearly indicate the need for more resources to be devoted to cancer registration, especially in the childhood age range, as part of an overall programme to improve the availability of diagnosis and treatment of this group of cancers, many of which have-potentially-an excellent prognosis.

Gastric teratoma: A series of 7 cases

BACKGROUND

Gastric teratoma is a rare entity comprising less than 1% of germ cell tumors of childhood. We present a series of seven gastric teratomas with a review of literature.

OBJECTIVE

To study the demographic profile, clinicopathological features and follow-up data of gastric teratomas.

METHODS

We did a retrospective analysis of 7 cases of gastric teratomas more than 15years and studied their demographic profiles, clinicopathological features and follow-up data.

RESULTS

We came across 7 cases of gastric teratomas out of which 5 were mature and 2 were immature. One case of immature teratoma came back with recurrence and another one had an unusual finding of presence of renal and pulmonary tissues, which has not been reported earlier.

CONCLUSION

Ours is the second largest case series of gastric teratomas in the pediatric age group and 2 out of 7 of our cases had immature elements. We also take this opportunity to report a case of gastric teratoma with the unusual histological finding of immature renal and pulmonary tissues, which has not been described previously.

Social and biological factors influencing the outcomes of children with Wilms tumors in Kenya and other Sub-Saharan countries

Wilms tumor (WT) is a common pediatric solid tumor, and the 5-year event-free survival rate of patients with this tumor has reached 85-90% in developed countries, whereas those in developing countries were reported to be less than 50%. To overcome these disparities, physicians and investigators in developed and developing countries are currently performing research with the aim of the better management of children with WT in Kenya and other Sub-Saharan countries. Axt and colleagues published a study that increased understanding of clinicopathology of WT in Kenya on the basis of a comprehensive web-based WT registry. The study revealed that patients enrolled in the National Health Insurance Fund (NHIF) showed better completion rate of therapy and better event-free survival than those not enrolled, indicating insufficient health coverage for those not enrolled in the NHIF. Approximately 20-30% of Kenyan population is estimated to be covered by some forms of health insurance, mostly by the NHIF. This could be improved through various approaches. The report described that 2-year event-free survival rate was 52.7% for all patients, although loss to follow up was 50%; the findings indicate large problems both in the study results and also in the completion of treatment. It is crucial to determine at which point patients stopped their treatment and why. The development of standardized treatment protocol for WT is an urgent agenda. We hope that researchers in developed countries and health providers in Kenya can work together in future to conquer disparities in the outcomes of children with WT.

Leukaemia in children in Papua New Guinea: an unusual pattern

We report data on 110 children aged <15 years diagnosed with leukaemia during two periods covering 13.25 years. The data sets were consistent. The reported incidence of leukaemia was low. Only 34 (31%) of the children were diagnosed with acute lymphoblastic leukaemia (ALL) compared with 54 (49%) children with acute myeloid leukaemia (AML). The overall mean (SD) age was 6.6 (3.5) years, 6.1 (3.5) for ALL and 6.9 (3.5) for AML. There was no evidence of an early childhood peak of ALL. The male : female ratio was 1.2 : 1 for all leukaemias, 1.3 for ALL and 1.25 for AML. Only eight (22%) of those diagnosed with ALL were classified as type L1. Our figures reflect a relative absence of the common (cALL) cell type in early childhood leukaemia and support the role of infection and its effect on the immune system in the aetiology of childhood leukaemia. Our data also revealed an unusually high proportion of chronic myeloid leukaemia (CML).

Childhood cancer incidence in British Indians & Whites in Leicester, 1996-2008

BACKGROUND

South Asians in England have an increased risk of childhood cancer but incidence by their individual ethnicities using self-assigned ethnicity is unknown. Our objective was to compare the incidence of childhood cancer in British Indians and Whites in Leicester, which has virtually complete, self-assigned, ethnicity data and the largest population of Indians in England.

METHODS

We obtained data on all cancer registrations from 1996 to 2008 for Leicester with ethnicity obtained by linkage to the Hospital Episodes Statistics database. Age-standardised incidence rates were calculated for childhood cancers in Indians and Whites as well as rate ratios, adjusted for age.

RESULTS

There were 33 cancers registered among Indian children and 39 among White children. The incidence rate for Indians was greater compared to Whites for all cancers combined (RR 1.82 (95% CI 1.14 to 2.89); p = 0.01), with some evidence of increased risk of leukaemia (RR 2.20 (0.95 to 5.07); p = 0.07), lymphoma (RR 3.96 (0.99 to 15.84); p = 0.04) and central nervous system tumours (RR 2.70 (1.00 to 7.26); p = 0.05). Rates were also higher in British Indian children compared to children in India.

CONCLUSIONS

British Indian children in Leicester had an increased risk of developing cancer compared to White children, largely due to a higher incidence of central nervous system and haematological malignancies.

Loss of heterozygosity at 11p13 and 11p15 in Wilms tumor: a study of 22 cases from India

PURPOSE

11p13 and 11p15 loss of heterozygosity (LOH) in Wilms tumor (WT), the commonest molecular pathogenetic event in WT, shows variation in different parts of the world. The present study looked for the presence of 11p13 and 11p15 LOH as well as nephrogenic rests in WT occurring in India.

METHOD

Twenty-two cases of WT were subjected to thorough pathological examination for presence of nephrogenic rests. Fresh frozen tissue was evaluated for LOH at 11p13 and 11p15, using PCR for microsatellite markers.

RESULTS

Among twenty-two consecutive cases of WT, 20 were unilateral and 2 were bilateral. 6/22 showed LOH at 11p13 (27.7 %) and 1/22 showed LOH at 11p15 (4.54 %). 2/22 cases showed presence of nephrogenic rests. One of the cases with LOH at 11p13 had intralobar nephrogenic rest in the adjacent kidney. One specimen had perilobar nephrogenic rest in the adjacent kidney but did not show LOH for either 11p13 or 11p15 in the tumor.

CONCLUSION

LOH at 11p13 is seen in 27.27 % of WT in India, which is similar to reports in the English language literature. LOH at 11p15 was seen in 4.54 % of WT, which is lower than that reported from Western subjects.

Different incidences of epigenetic but not genetic abnormalities between Wilms tumors in Japanese and Caucasian children

Epidemiological studies show that the incidence of Wilms tumor (WT) in East-Asian children is half of that in Caucasian children. Abnormalities of WT1, CTNNB1, WTX, and IGF2 were reported to be involved in Wilms tumorigenesis in Caucasians, although none of the studies simultaneously evaluated the four genes. WTX forms the β-catenin degradation complex; however, the relationship between WTX abnormality and CTNNB1 mutation was uncertain in WTs. We examined abnormalities of the four genes in 114 Japanese with WTs to clarify the relationship between genetic and epigenetic factors and the incidence of WTs. We found that abnormalities of WTX and CTNNB1 were mutually exclusive, and that although CTNNB1 mutation was frequent in WTs with WT1 abnormality, but rare in WTs without, the incidences of WTX abnormality were similar between WTs with or without WT1 abnormality. These findings were consistent with those reported in Caucasian populations, and indicate multiple roles of WTX abnormality. Abnormalities of WT1, WTX and CTNNB1, and loss of IGF2 imprinting (LOI) were detected in 31.6%, 22.8%, 26.3%, and 21.1% of the 114 WTs, respectively. When we selected 101 sporadic WTs, the incidences of WT1, CTNNB1, or WTX abnormality were generally comparable between the two populations, whereas the incidence of IGF2 LOI was lower in Japanese than that of IGF2 LOI reported in Caucasians (P = 0.04). This is the first comprehensive study of the four genes, and the results supported the hypothesis that the lower incidence of IGF2 LOI contributes to the lower incidence of WTs in Japanese children.

Rhabdomyosarcoma in children: a SEER population based study

OBJECTIVE

To examine incidence and outcomes for pediatric rhabdomyosarcoma (RMS).

METHODS

The SEER registry was examined for patients with RMS < 20 y old.

RESULTS

Overall, 1544 patients were identified for an incidence of 0.4414/100,000 per year. Males outnumbered females 3:2. Tumors were classified as embryonal (67%), alveolar (32%), and pleomorphic (1%). Alveolar and pleomorphic RMS were more common in adolescents, whereas embryonal type was more common in younger children (P = 0.0001). Pleomorphic (47%) and alveolar (39%) RMS commonly presented with distant disease, in contrast to embryonal (25%). Most patients had surgical resection (81%) and radiotherapy (63%). Overall, 5- and 10-y survival was 60% and 57%, respectively. Univariate analysis identified higher survival for age < 10 y, local stage, favorable site, embryonal type, <5 cm tumor size, and surgical resection. Multivariate analysis identified non-embryonal type (HR 1.451), non-favorable site (HR 1.570), no surgery (HR 1.726), age ≥ 10 y (HR 1.734), 1973-1978 diagnosis year (HR 1.730), and distant disease (HR 3.456) as independent predictors of mortality.

CONCLUSIONS

Embryonal histology, the most common type of pediatric RMS, presents in young children and has better prognosis than alveolar or pleomorphic types. Patients with embryonal tumors, favorable tumor location, age < 10 y, localized disease, and surgical resection have improved survival.

Cancer incidence among the south Asian and non-south Asian population under 30 years of age in Yorkshire, UK

Background:

Few studies have examined epidemiological differences between ethnic groups for children and young adults with cancer.

Methods:

Subjects aged 0–29 years, diagnosed between 1990 and 2005 in the former Yorkshire Regional Health Authority, were included in the analysis. Ethnicity (south Asian or not) was assigned using name analysis program and Hospital Episode Statistics data. Differences in incidence (per 1 000 000 person-years) rates and trends were analysed using joinpoint and Poisson regression analysis.

Results:

Overall cancer incidence was similar for south Asians (12.1, 95% CI: 10.7–13.5; n=275) and non-south Asians (12.6, 95% CI: 12.2–13.1; n=3259). Annual incidence rates increased significantly by 1.9% per year on average (95% CI: 1.2–2.6%), especially for south Asians (7.0% 95% CI: 4.2–9.9%).

Conclusion:

If present trends continue, the higher rate of increase seen among south Asians aged 0–29 years in Yorkshire will result in three times higher cancer incidence than non-south Asians by 2020.

Ethnicity and incidence of Hodgkin lymphoma in Canadian population

Background

Research has shown that ethnicity is a significant predictor of Hodgkin lymphoma (HL). Variations in cancer incidence among ethnic groups in the same country can lead to important information in the search for etiological factors. Other risk factors important in the etiology of HL are medical history and exposure to pesticides. In this report we investigated the association between ethnicity and HL in the presence of medical history, and exposure to pesticides.

Methods

The data resulting from a matched population-based case-control study conducted in six provinces of Canada (Ontario, Quebec, Manitoba, Saskatchewan, Alberta, and British Columbia) was analyzed to determine whether or not there was any association between ethnicity and incidence of HL when adjusted for personal medical history and pesticide exposure. Information on ethnicity, personal medical history, and pesticide exposure was collected by questionnaires via mail on 316 men diagnosed with HL; and on 1506 controls. A conditional logistic regression was utilized and results were presented as odds ratios and 95% confidence intervals.

Results

In our study population, the distribution of ethnic groups was: 38.5% North American, 15% British, 8.4% Western European, 8.2% Eastern European, 1.7% Asian, 1.4% Scandinavian and 27% of other ethnic origin. Compared to North Americans (i) the risk of HL was greater among the Eastern European descendents (Odds Ratio (OR_adj): 1.82; 95% confidence interval (CI): 1.02, 3.25) and Western European (OR_adj: 1.62; 95% CI: 0.95–2.76) descent population (borderline significance at 5% level); and (ii) the risk of HL was lower in Asian descents. Diagnosis with measles (OR_adj: 0.72, 95% C.I.: 0.53–0.98) and/or positive history of allergy desensitization shots (OR_adj: 0.55, 95% C.I.: 0.30–0.99) were negatively associated with the incidence of HL, while diagnosis with acne (OR_adj: 2.12, 95% C.I.: 1.19–3.78), shingles (OR_adj: 2.41, 95% C.I.: 1.38–4.22) and positive family history of cancer (OR_adj: 1.93, 95% C.I.: 1.40–2.65) increased the risk of HL. Exposure to individual herbicide dichlorprop showed an increased risk of HL (OR_adj: 6.35, 95% C.I.: 1.56–25.92).

Conclusion

In Canada, compared to North Americans descendents, the risk of HL was significantly greater among the Eastern European and Western European descent population. Our results related to association between ethnicity and HL support the findings reported by other researchers. Our data showed that subjects who were diagnosed with measles or had allergy desensitization shots negatively associated with the incidence of HL; and other medical conditions, ever diagnosed with acne, and positive family history of cancer were positively associated with the incidence of HL.

Quality, comparability and methods of analysis of data on childhood cancer in Europe (1978–1997): Report from the Automated Childhood Cancer Information System project

In collaboration with 62 population-based cancer registries contributing to the Automated Childhood Cancer Information System (ACCIS), we built a database to study incidence and survival of children and adolescents with cancer in Europe. We describe the methods and evaluate the quality and internal comparability of the database, by geographical region, period of registration, type of registry and other characteristics. Data on 88,465 childhood and 15,369 adolescent tumours registered during 1978-1997 were available. Geographical differences in incidence are caused partly by differences in definition of eligible cases. The observed increase in incidence rates cannot be explained by biases due to the selection of datasets for analyses, and only partially by the registration of non-malignant or multiple primary tumours. Part of the observed differences in survival between the regions may be due to variable completeness of follow-up, but most is probably explained by resource availability and organisation of care. Further standardisation of data and collection of additional variables are required so that this study may continue to yield valuable results with reliable interpretation.

Geographical patterns and time trends of cancer incidence and survival among children and adolescents in Europe since the 1970s (the ACCISproject): an epidemiological study

BACKGROUND

Cancer is rare before age 20 years. We aimed to use the European database of childhood and adolescent cancer cases, within the Automated Childhood Cancer Information System project, to estimate patterns and trends of incidence and survival within Europe.

METHODS

Comparable, high-quality data from 63 European population-based cancer registries consisted of 113000 tumours in children and 18243 in adolescents diagnosed in 1970-99. Incidence rates and survival were compared by region (east vs west), period, and malignant disease.

FINDINGS

In the 1990s, age-standardised incidence rates were 140 per million for children (0-14 years) and 157 per million for ages 0-19 years. Over the three decades, overall incidence increased by 1.0% per year (p<0.0001) in children (increases for most tumour types), and by 1.5% (p<0.0001) in adolescents (15-19 years; notable increases were recorded for carcinomas, lymphomas, and germ-cell tumours). Overall 5-year survival for children in the 1990s was 64% in the east and 75% in the west, with differences between regions for virtually all tumour groups; 5-year survival was much the same in adolescents. Survival has improved dramatically since the 1970s in children and adolescents, more so in the west than in the east.

INTERPRETATION

Our results are clear evidence of an increase of cancer incidence in childhood and adolescence during the past decades, and of an acceleration of this trend. Geographical and temporal patterns suggest areas for further study into causes of these neoplasms, as well as providing an indicator of progress of public-health policy in Europe.

Incidence of childhood leukaemia and non-Hodgkinʼs lymphoma in France: National Registry of Childhood Leukaemia and Lymphoma, 1990–1999

The French National Registry of Childhood Leukaemia and Lymphoma (NRCL) covers the whole French mainland population aged less than 15 years (approximately 11 million children) for all childhood haematopoietic tumours since 1 January 1990, except Hodgkin's disease, which has been registered since 1 January 1999. During the period from 1990 to 1999, 5757 cases of leukaemia, lymphoma and myelodysplastic syndrome were registered in the NRCL, with an average of 2.5 sources per case. The age-standardized incidence rates per million per year were 43.1 for leukaemia (34.3 for acute lymphoblastic leukaemia, 7.1 for acute myeloblastic leukaemia, 0.6 for chronic myeloid leukaemia and 0.5 for chronic myelomonocytic leukaemia), 8.9 for non-Hodgkin's lymphomas and 6.7 for Hodgkin's disease. Down's syndrome was present in 110 cases of acute leukaemia (2.5%) and three cases of non-Hodgkin's lymphoma (0.3%). The incidence of acute lymphoblastic leukaemia showed a typical peak at age 2 years for girls and 3 years for boys. The incidence rates of leukaemia and non-Hodgkin's lymphoma did not show any temporal trends over the 10 year period.

Epigenetic differences between Wilms' tumours in white and east-Asian children

BACKGROUND

Variations in the international incidence of Wilms' tumour might be due to genetic factors. The maternal insulin-like growth factor 2 gene (IGF2) is imprinted in normal tissues, whereas in some Wilms' tumours and other tumour types the imprint is lost, leading to biallelic transcription of IGF2. We investigated whether the difference in incidence of Wilms' tumour between children of east-Asian descent and white children is due to variations in proportion of tumours with loss of IGF2 imprinting (IGF2 LOI).

METHODS

We assessed IGF2 LOI by use of an ApaI polymorphism in IGF2 exon 9 or quantitative PCR measuring DNA methylation of the H19 and KvDMR1 alleles. The frequencies of perilobar nephrogenic rests associated with Wilms' tumour were assessed histologically in Japanese children and children of white and east-Asian descent.

FINDINGS

IGF2 LOI was present in Wilms' tumours from predominantly white children from New Zealand (13 of 41 tumours) but absent in tumours from Japanese children (0 of 21 tumours; difference in proportions 0.32, 95% CI 0.07-0.52). Frequency of perilobar nephrogenic rests accompanying tumours from white American children (1192 of 5002, 24%) was significantly higher than in Japanese (one of 56, 1%, difference in proportions 0.22, 95% CI 0.14-0.25) and east-Asian American children (seven of 92, 8%, 0.16, 0.09-0.21).

INTERPRETATION

Wilms' tumours in the east-Asian population rarely arise from the IGF2 LOI mechanism frequently noted in white patients. Our findings that IGF2 LOI and perilobar nephrogenic rests associated with this mechanism arise at low frequency in Japanese and east-Asian American children lend support to this conclusion. Variation in frequency of this epigenetic mechanism provides one explanation for the difference in incidence of Wilms' tumour between populations.

Pediatric sinonasal rhabdomyosarcoma: three cases and a review of the literature

OBJECTIVE

To understand the clinical presentation, management, and natural history of paranasal rhabdomyosarcoma.

DESIGN

Retrospective case series review.

METHODS

Retrospective medical record review of patients less than 20 years of age who presented to our facility with rhabdomyosarcoma of the nasal cavity or paranasal sinuses.

RESULTS

Medical records of all pediatric patients seen in our pediatric otolaryngology clinic were reviewed from January 1, 1995, through December 31, 2000. Three patients were identified with sinonasal rhabdomyosarcoma. Their presentation, evaluation, and treatment were evaluated. Relevant literature 1966 to the present was reviewed with the assistance of Medline.

CONCLUSIONS

Rhabdomyosarcoma is an aggressive pediatric malignancy, requiring a high index of suspicion to detect it in its earliest stages. Patients with suggestive symptoms should undergo a full evaluation including nasal endoscopy and imaging. Because the current chemotherapy protocols are more effective on localized disease, early diagnosis is crucial to patient survival.

Patterns of childhood cancer by ethnic group in Bradford, UK 1974-1997

The highly urbanised northern English city of Bradford contains a diverse population from different ethnic backgrounds, including a high proportion of south Asians. We aimed to identify the effect of ethnic group on the incidence and temporal trends of childhood cancer in Bradford. Children (0-14 years) from the district of Bradford, who were diagnosed with a malignancy between 1974 and 1997, were selected from a population-based register. Each child was classified as south Asian (Indian, Pakistani and Bangladeshi), or not, based on their full name using 2 computer algorithms and individual inspection. Mid-year population estimates were used to calculate incidence rates and differences were assessed using Poisson regression. The study included 318 children, of whom 81 (25%) were south Asian. The incidence of all cancers in south Asian children (14.9 per 100,000 person years, 95% CI 11.6-18.2) was higher than non-south Asian children (12.0, 10.5-13.5) although not significantly so (P=0.14). Comparisons by diagnostic subgroup showed no major differences apart from significantly higher rates of acute myeloid leukaemia (AML) in south Asian children (1.9 versus 0.7, P=0.02). The age-specific incidence peaks of all childhood cancers and leukaemias were present in south Asian children aged 5-9 years compared with 0-4 years olds in the non-south Asian population. Non-significant increases of 1.4 and 1.5% in the average annual incidence of all cancers were seen for south Asians and non-south Asians respectively, with a significant rise for non-south Asians with leukaemia of 3.0% (P=0.04). Our timely study shows patterns of occurrence of childhood cancer that differ with respect to ethnic group. Differences are particularly apparent in the excess of AML and incidence peak in 5-9 year olds in south Asian children.

Hodgkin's disease in Asians: incidence patterns and risk factors in population-based data

Hodgkin's disease (HD) has been reported to be rare in Asians. Data sparseness has hindered studies exploring the relative contributions of environment and heredity to HD etiology, and individual risk factors have never been studied in an Asian population. With the most recent, uniformly collected population-based data from the US and Asia, we compared HD incidence rates in Chinese, Japanese, Filipinos, and Asian Indians in the US and in Asia. HD incidence rates were quite low in all Asian subgroups, but approximately double in US Asians as in native Asians. In both, rates were lower for Japanese and Chinese than for Filipinos and Asian Indians. A modest young-adult rate peak occurred for most US Asian groups, but not for any population in Asia. In data from a population-based case-control study of HD in San Francisco area women, young-adult Asian cases, like young-adult cases of other racial/ethnic groups, had childhood social environments indicative of less early contact with children. Given environmental and lifestyle differences between the US and Asia, the consistently low rates of HD in Asians suggest genetic resistance to disease development, possibly associated with HLA type. International and inter-ethnic differences, and risk factor patterns in case-control data, implicate environmental influences in the etiology of HD.

South Asian ethnicity and material deprivation increase the risk of Epstein-Barr virus infection in childhood Hodgkin's disease

In order to further define the factors associated with the observed variations in the Epstein-Barr virus-positive rate in childhood Hodgkin's disease, we have studied the effect of material deprivation (measured by the Townsend score) and ethnic origin on the frequency of Epstein-Barr virus-positivity in 55 cases of childhood Hodgkin's disease, diagnosed between 1981 and 1999, from a multi-ethnic region of the United Kingdom. Epstein-Barr virus status was determined by immunohistochemistry for the Epstein-Barr virus-encoded latent membrane protein-1. 62% of cases were Epstein-Barr virus-positive. Ethnic group was the strongest predictor of Epstein-Barr virus-positivity, with South Asians having a more than 20-fold risk of being Epstein-Barr virus-positive compared with non-South Asians. An increased risk was still present after adjusting for deprivation. Townsend scores were significantly higher (indicating more deprivation) in the Epstein-Barr virus-positive group, particularly in males. The relative risk of Epstein-Barr virus-positivity showed a gradient with increasing Townsend score; the risk being 7-times higher in the most deprived quartile compared with the least deprived group. Although the association between Townsend score and Epstein-Barr virus-positivity was reduced after adjusting for ethnic group, the risk of Epstein-Barr virus-positivity was still 3-times higher in the most deprived compared with the least deprived quartile. In addition, cases having 2 or more siblings were 5-times as likely to be Epstein-Barr virus-positive as those from smaller families. These results provide the first evidence of a strong association between Epstein-Barr virus-positive Hodgkin's disease and South Asian children from the United Kingdom. In addition, deprivation may increase the likelihood of Epstein-Barr virus-positive disease independently of ethnicity.

Lymphoma and lymphoid leukemia incidence in Florida children: ethnic and racial distribution

BACKGROUND

Incidence reports for pediatric lymphoma and lymphoid leukemia in Hispanic subpopulations in the United States are rare. The authors hypothesized that Florida's Hispanic children would have higher risks of lymphoma and lymphoid leukemia compared with non-Hispanic white children.

METHODS

All cases of lymphoid leukemia, Hodgkin, non-Hodgkin, and Burkitt lymphoma (SEER International Classification of Diseases for Oncology codes) in children (< 15 years) in the Florida Cancer Data System (FCDS) from 1985 to 1997 were studied. Cases were classified as: 1) white, 2) Hispanic, or 3) black, and stratified by age. Age-adjusted rates for the three race-ethnic groups were calculated. Rates for Hispanics and blacks were compared with whites as standardized rate ratios (SRR) with 95% confidence intervals.

RESULTS

Seven hundred thirty-one incident cases of pediatric lymphoma and 1231 cases of lymphoid leukemia were identified during the study period. For children with lymphoma, the SRR for Hispanics was 1.32 (95% CI, 1.20-1.44), and for blacks, the SRR was 0.68 (95% CI, 0.63-0.72. For lymphoid leukemia, the SRR for Hispanics was 1.29 (95% CI, 1.28-1.30), and for blacks, the SRR was 0.55 (95% CI, 0.54-0.56). Similar rates were found for the Hodgkin and non-Hodgkin subgroups.

CONCLUSIONS

Incidences of Hodgkin and non-Hodgkin lymphoma were significantly higher in Florida's Hispanic children, with 30% increased relative risks, compared with whites. Black children had significantly decreased incidences and risk. Results for lymphoid leukemia were similar. Incidence of lymphoma in Florida's Hispanic children (primarily Cuban and Central American origin) differed from similar reports from Texas and California, where Hispanics are primarily of Mexican origin.

Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and risk of molecularly defined subtypes of childhood acute leukemia

Low folate intake as well as alterations in folate metabolism as a result of polymorphisms in the enzyme methylenetetrahydrofolate reductase (MTHFR) have been associated with an increased incidence of neural tube defects, vascular disease, and some cancers. Polymorphic variants of MTHFR lead to enhanced thymidine pools and better quality DNA synthesis that could afford some protection from the development of leukemias, particularly those with translocations. We now report associations of MTHFR polymorphisms in three subgroups of pediatric leukemias: infant lymphoblastic or myeloblastic leukemias with MLL rearrangements and childhood lymphoblastic leukemias with either TEL-AML1 fusions or hyperdiploid karyotypes. Pediatric leukemia patients (n = 253 total) and healthy newborn controls (n = 200) were genotyped for MTHFR polymorphisms at nucleotides 677 (C-->T) and 1,298 (A-->C). A significant association for carriers of C677T was demonstrated for leukemias with MLL translocations (MLL+, n = 37) when compared with controls [adjusted odd ratios (OR) = 0.36 with a 95% confidence interval (CI) of 0.15-0.85; P = 0.017]. This protective effect was not evident for A1298C alleles (OR = 1.14). In contrast, associations for A1298C homozygotes (CC; OR = 0.26 with a 95% CI of 0.07--0.81) and C677T homozygotes (TT; OR = 0.49 with a 95% CI of 0.20--1.17) were observed for hyperdiploid leukemias (n = 138). No significant associations were evident for either polymorphism with TEL-AML1+ leukemias (n = 78). These differences in allelic associations may point to discrete attributes of the two alleles in their ability to alter folate and one-carbon metabolite pools and impact after DNA synthesis and methylation pathways, but should be viewed cautiously pending larger follow-up studies. The data provide evidence that molecularly defined subgroups of pediatric leukemias have different etiologies and also suggest a role of folate in the development of childhood leukemia.

Cancer and men from minority ethnic groups: an exploration of the literature

The authors reviewed literature which has been published in the last 20 years. Cancer is the second leading cause of death in developed countries and is expected to become a significant cause of death in developing countries. Whilst there are a large number of studies on cancer and men, there is a paucity of data on men from minority ethnic groups. In the USA, African Americans are more likely to develop cancer than any other ethnic group. Although cancer rates amongst minority ethnic groups in the UK are thought to be low, 11% of Indian and African men and 19% of Caribbean men died from cancer during 1979-1983. There is also further evidence in the USA that African American, Filipinos and Native Americans have the lowest cancer survival rates. Service utilization, especially tertiary care, is also thought to be low amongst minority ethnic groups from the USA and the UK. Reasons for these variations include artefactual, cultural, materialist and social selectivist explanations as well as the effects of migration, racism and genetic disposition. This area is under-researched, in particular cultural beliefs about cancer. Further research into this area should apply culturally competent methods to ensure valid data to inform cancer policy, education and practice.

Incidence of childhood cancer in Ho Chi Minh City, Vietnam, 1995-97

Incidence rates of childhood cancer for the city of Ho Chi Minh are presented for the first time. For the 3-year period 1995-97, a total of 302 cancer cases were registered in children under 15 years of age, with a male to female ratio of 1.1. The overall crude rate was 78.8 and the age-standardised incidence rate was 88.4 per million person-years, which was low in comparison with other countries in eastern Asia and with the predominantly white population of Australia. Leukaemia (principally acute lymphocytic), brain tumours and lymphomas were the most common childhood neoplasms, which is consistent with the pattern observed in other registries of the region. The rate of retinoblastoma was higher than in the other regional registries. On the other hand, no cases of hepatocellular carcinoma were registered.

Ethnic group and survival from childhood cancer: report from the UK Children's Cancer Study Group

Survival following cancer was analysed in relation to ethnic group among children diagnosed in Britain during 1981-1996 and treated at paediatric oncology centres by members of the UK Children's Cancer Study Group. Survival was analysed for 11 diagnostic groups: acute lymphoblastic leukaemia (ALL), acute non-lymphocytic leukaemia, Hodgkin's disease, non-Hodgkin's lymphoma, astrocytoma, primitive neuroectodermal tumour, neuroblastoma, Wilms' tumour, osteosarcoma, Ewing's sarcoma and rhabdomyosarcoma. There were no significant differences in survival between White and non-White children over the study period as a whole. Among children with ALL, however, the relative risk of death allowing for period of diagnosis, age and white blood count was 1.25 for those of South Asian ethnic origin compared with Whites (P = 0.057).

Survival from childhood cancer in Yorkshire, U.K.: effect of ethnicity and socio-economic status

The effect of ethnicity and socio-economic status on the survival of a population-based cohort of 1979 children diagnosed with cancer between 1974 and 1995 was investigated. Ethnicity was assigned by computer algorithms and visual inspection as south Asian (or not) for each child, based on their full name. Socio-economic status was measured using the Carstairs index, based on census areas of case residence at diagnosis. 15 children (0.8%) were lost to follow-up. Log-rank tests showed survival from all cancers did not differ between south Asians and other children and no increased risk was observed for south Asians in any diagnostic category, although numbers were small. Increasing levels of deprivation were associated with significant trends of poorer survival from all cancers, leukaemias and brain tumours. Risk of death was typically higher for children from the most deprived areas although differences were not statistically significant after accounting for other factors including ethnicity. Taking all children with malignant disease together, neither ethnicity nor socio-economic status appear to influence survival after taking other factors into consideration.

Effect of material deprivation on Epstein-Barr virus infection in Hodgkin's disease in the West Midlands

We have used Townsend scores from postcode data to compare levels of material deprivation and Epstein-Barr virus (EBV)-positivity for 223 patients diagnosed with Hodgkin's disease (HD) in the period 1981-1997. The presence of EBV in HD tumours was determined using in situ hybridization to target the abundantly expressed EBV early RNAs. EBV was detected in the malignant Hodgkin and Reed-Sternberg cells in 47/223 HD cases (21%). There was found to be a tendency for higher Townsend scores (indicative of higher levels of material deprivation) in EBV-positive HD patients, but this association was not statistically significant. When various subgroups of patients from the study were examined separately the indication of higher Townsend scores in EBV-positive patients was found to be more marked for patients with mixed cellularity disease (P = 0.09) and for females (P = 0.03). The results of this study suggest that differences in the level of material deprivation are important in determining the likelihood of EBV-positive HD in the UK, particularly for certain subgroups of patients. It is not known what specific socioeconomic factors are responsible for these differences, although alterations in the timing or rate of primary EBV infection, or decline in the level of EBV-specific immunity, may be important.

Cancer incidence in the south Asian population of England (1990-92)

Cancer incidence among English south Asians (residents in England with ethnic origins in India, Pakistan or Bangladesh) is described and compared with non-south Asian and Indian subcontinent rates. The setting for the study was areas covered by Thames, Trent, West Midlands and Yorkshire cancer registries. The study identified 356 555 cases of incident cancer (ICD9:140-208) registered between 1990 and 1992, including 3845 classified as English south Asian. The main outcome measures were age specific and directly standardized incidence rates for all cancer sites (ICD9:140-208). English south Asian incidence rates for all sites combined were significantly lower than non-south Asian rates but higher than Indian subcontinent rates. English south Asian rates were substantially higher than Indian subcontinent rates for a number of common sites including lung cancer in males, breast cancer in females and lymphoma in both sexes. English south Asian rates for childhood and early adult cancer (0-29 years) were similar or higher than non-south Asian rates. English south Asian rates were significantly higher than non-south Asian rates for Hodgkin's disease in males, cancer of the tongue, mouth, oesophagus, thyroid gland and myeloid leukaemia in females, and cancer of the hypopharynx, liver and gall bladder in both sexes. The results are consistent with a transition from the lower cancer risk of the country of ethnic origin to that of the country of residence. They suggest that detrimental changes in lifestyle and other exposures have occurred in the migrant south Asian population.

What causes Hodgkin's disease in children?

Hodgkin's disease is one of the commonest cancers of older children and adolescents, but little is known about its aetiology. Recent data, particularly in descriptive epidemiology and virology, tend to confirm the 'two-disease' hypothesis. Mixed cellularity Hodgkin's disease is more common, especially at younger ages, in poorer socioeconomic environments, whereas nodular sclerosing Hodgkin's disease has a higher incidence in more affluent societies. Approximately three-quarters of childhood Hodgkin's disease, and a higher proportion of the mixed cellularity subtype, may be a rare response to Epstein-Barr virus infection, together with an unidentified cofactor related to the degree of affluence of the population. Other infectious agents may be implicated in some cases. The already low incidence, especially of nodular sclerosis, among populations of East Asian ethnic origin and the high incidence, especially of mixed cellularity, among some populations of South Asian origin are apparently independent of socioeconomic status. This ethnic variation in risk suggests that genetic predisposition also plays a role. Detailed HLA studies may help to elucidate the complex variations between populations in the risk of Hodgkin's disease and its principal subtypes.

Childhood cancer and paternal employment in agriculture: the role of pesticides

Previous studies have suggested that the offspring of men potentially exposed to pesticides at work may be at increased risk of kidney cancer (Wilms' tumour), brain tumours, Ewing's bone sarcoma and acute leukaemia. This paper examines the association between potential occupational exposure of fathers to pesticides and offspring's death from cancer in a large national database. Records for 167703 childhood deaths occurring during 1959-63, 1970-78 and 1979-90 in England and Wales have been analysed. Among the offspring of men with potential occupational exposure to pesticides there were 5270 deaths, of which 449 were due to cancer. Associations were assessed using proportional mortality ratios (PMRs), with adjustment for age, year of death and paternal social class. Of the childhood cancers previously linked with potential paternal occupational exposure to pesticides, the only statistically significant excess was for kidney cancer (PMR=1.59, 95% CI=1.18-2.15, based on 42 deaths). Although these results offer some support for the suggestion that paternal occupational exposure to pesticides may be related to the subsequent development of kidney cancer in offspring, other explanations cannot be excluded. In the light of the findings presented here and elsewhere, further, more detailed, research into the nature of this relationship is warranted.

Hodgkin's disease in children in southern Africa: epidemiological characteristics, morbidity and long-term outcome

We reviewed 39 children < 15 years of age treated for Hodgkin's disease (HD) from 1973 to 1996. There were seven black, 12 white and 20 coloured children (of mixed ethnic origin). The M:F ratio was 2.9:1 and the median ages 147, 124 and 119 months in white, coloured and black children, respectively. Coloured and black children came mainly from a poor socio-economic background. Cervical lymphadenopathy was present in 74% and systemic symptoms in 51% of cases. Five per cent had clinical stage I, 41% stage II, 28% stage III and 26% stage IV disease. Two children underwent a staging splenectomy. The majority of white children presented with stages I and II and the majority of black and coloured children with stages III and IV HD. Nodular sclerosing (59%), mixed cellularity (40%) and lymphocyte-depleted (43%) were the most common histological subtypes in white, coloured and black children, respectively. Epidemiologically, white children fitted the criteria for HD type I and coloured and black children the criteria for HD type III. Nineteen children were treated with ChlVPP (chlorambucil, vinblastine, prednisone, procarbazine) and 20 with MOPP (mustine, Oncovin, procarbazine, prednisone) and/or ABVD (Adriamycin, bleomycin, vinblastine, DTIC) with involved field radiotherapy to bulky mediastinal disease. The projected 10-year survival after ChlVPP or MOPP/ABVD therapy was similar at 52%. In stages I and II, HD projected survival at 5 and 10 years was 85%, and in stages III and IV it was 82% at 5 and 48% at 10 years. The relapse rate was 47% in stage II, 45% in stage III and 44% in stage IV. Tuberculosis was suspected and treated in five children at the time of, and in seven children (three confirmed) subsequent to, the diagnosis of HD. Varicella developed in six and herpes zoster in five children. Five treatment-related deaths were due to septicaemia following splenectomy (two), marrow failure, corpulmonale and secondary leukaemia.

High risk of lymphomas in children of Asian origin: ethnicity or confounding by socioeconomic status?

To examine the role of ethnic origin as a risk factor for paediatric lymphoma, a cancer registry-based analysis was undertaken in Yorkshire, UK. Children of Asian ethnic origin were found to have an odds ratio for lymphomas of 1.60 (CI 0.98-2.62), after adjusting for age and sex. After adjusting also for 'super profile group' as an indicator of socioeconomic status, the estimate became 1.99 (CI 1.08-3.68). Hodgkin's disease and non-Hodgkin's lymphomas were analysed separately with similar results. Super profile group is an area-based measure and may not reflect the individual variation in living standards, especially among the Asian immigrants. Our results indicate that socioeconomic status does not confound the relationship between lymphomas and ethnic origin. However, there is a need for studies of ethnicity that include indicators of individual living standards or socioeconomic status.

Cancer in minority ethnic populations: priorities from epidemiological data

The aim of this paper is to review the literature on the frequency of cancers to develop priorities for cancer policy, prevention, services and research for black and minority ethnic populations in Britain. Data on populations originating in the Indian sub-continent, and Caribbean and African Commonwealth were extracted from published works. Cancers were ranked (top seven) on the basis of the number of cases, actual frequency, and also on relative frequency (SMR, SRR, PMR). Cancer was found to be a common cause of death. For example, during 1979-83 the proportion of deaths resulting from neoplasms in immigrants living in England and Wales was 11% for Indian and African men aged 20-49, and 19% for Caribbeans. The corresponding proportions were higher among women. The pattern of cancer depended on the method used to assess rankings. On the basis of the number of cases the top 3 ranking cancers for adults were breast, long and neoplasms of the lymphatic system. Based on SMR's cancer of the gallbladder, liver and oral cavity ranked amongst the top 3 for adults. For children the top ranking cancers were acute lymphoblastic leukaemia, central nervous system tumours and neuroblastoma. Variations by ethnic group were more evident in the rankings of relative frequency than in rankings based on numbers of cases. In conclusion, the most common and preventable cancers among minority ethnic populations were the same as those for the general population. The different cancer pattern based on SMRs highlight additional needs and provide potential models for research into understanding the causes of these cancers. Health services policy and practice should ensure that the common and preventable cancers take priority over rare cancers and those for which there is no effective treatment or prevention. Priorities for policy, prevention, clinical care and research should be set separately, for they differ.

Epidemiology of childhood leukemia in Hokkaido, Japan

The population-based epidemiological indices (crude incidence, survival rate, mortality, etc.) of childhood leukemia (0-14 years of age) from 1969 to 1993 in Hokkaido Prefecture, Japan, were calculated, using data obtained from the Registry of Childhood Malignancies in Hokkaido Prefecture. A total of 1,084 cases of leukemia were diagnosed in the 1969-93 period. The annual incidence of all types of leukemia from 1984 to 1993 was about 4 per 100,000 children aged 0-14 years, with the incidence of ANLL decreasing slightly and that of ALL increasing. The ratio of ALL/ANLL could similarly be seen to be increasing in all age groups. Out of a cohort of 100,000 live births, about 65 children developed leukemia by 14 years of age, and in this longitudinal observation the ratio of ALL/ANLL was increasing. The incidence of ALL and ANLL and the ratio of ALL/ANLL in Japanese children are approaching those of Caucasians. Approximately 80% of the ALL cases were of the LI type (FAB classification), and about 65% of these could be immunologically classified as "common" ALL. The 5-year survival rate of T- and B-cell ALL cases was 50% or less, while that of "common" ALL cases was about 80%.

Cancer and congenital abnormalities in Asian children: a population-based study from the West Midlands

Cancer and associated congenital abnormalities were investigated in Muslim and non-Muslim Asian children from the West Midlands. Cancer incidence rates were calculated for Indian (non-Muslim), Pakistani/Bangladeshi (Muslim) and white children diagnosed from 1978 to 1992. Incidence was significantly higher in the Pakistanis, with an age-standardised rate (ASR) of 163 cases per million per year, compared with 115 for Indian and 125 for white children. Among Asian cancer patients, congenital malformations were significantly more common in Muslim (21%) compared with non-Muslim (7%). In Muslims the malformation excess was caused by autosomal recessive and dominant disorders (in 8% and 5% of cases respectively). Cancer malformation/predisposition syndromes were found in 10% of Muslims, compared with 2% of non-Muslims. In 33% of the Muslims with malformations, childhood cancer and a malformation were also present in a close relative. None of the non-Muslims with malformations had a relative with childhood cancer. The cancer excess in Muslims may be partly related to inherited genes causing both malformations and cancer. The prevalence of autosomal recessive disorders may be related to consanguinity, which is common in the Pakistani Muslim population. The high incidence of autosomal dominant disorders may be related to older paternal age at conception, giving rise to spontaneous mutations.

Immunological subtypes of childhood acute lymphoblastic leukemia in Bulgaria

With regards to the geographical variation in acute lymphoblastic leukemia (ALL) distribution, we present data from the immunophenotyping of 171 newly diagnosed cases of childhood ALL in Bulgaria during a 4 year period (1990-1994). On the basis of 17 phenotypic markers the distribution of immunological subtypes was as follows: AUL 4%; Pro-B ALL 13%; common ALL 42%; Pre-B ALL 11%; B-ALL 1%; T-ALL 28% and unclassified 2%. Most of the cases were between 2 and 5 years of age. Common ALL was predominant (53%) in this age group. The male:female ratio was 1.7:1. The frequency of T-ALL (28%) was significantly higher (P < 0.01; t = 3.49) in comparison to that reported for the U.S.A. and West European countries (mean 13%). It was close to the frequency reported by some authors for France (20%), Greece (26%) and south Italy (28.1%). These countries and Bulgaria might form an environmental area with a moderate frequency of T-ALL.