Acute urinary retention and risk of cancer: population based Danish cohort study

OBJECTIVE

To examine the risk of urogenital, colorectal, and neurological cancers after a first diagnosis of acute urinary retention.

DESIGN

Nationwide population based cohort study.

SETTING

All hospitals in Denmark.

PARTICIPANTS

75 983 patients aged 50 years or older with a first hospital admission for acute urinary retention during 1995-2017.

MAIN OUTCOME MEASURES

Absolute risk of urogenital, colorectal, and neurological cancer and excess risk of these cancers among patients with acute urinary retention compared with the general population.

RESULTS

The absolute risk of prostate cancer after a first diagnosis of acute urinary retention was 5.1% (n=3198) at three months, 6.7% (n=4233) at one year, and 8.5% (n=5217) at five years. Within three months of follow-up, 218 excess cases of prostate cancer per 1000 person years were detected. An additional 21 excess cases per 1000 person years were detected during three to less than 12 months of follow-up, but beyond 12 months the excess risk was negligible. Within three months of follow-up the excess risk for urinary tract cancer was 56 per 1000 person years, for genital cancer in women was 24 per 1000 person years, for colorectal cancer was 12 per 1000 person years, and for neurological cancer was 2 per 1000 person years. For most of the studied cancers, the excess risk was confined to within three months of follow-up, but the risk of prostate and urinary tract cancer remained increased during three to less than 12 months of follow-up. In women, an excess risk of invasive bladder cancer persisted for several years.

CONCLUSIONS

Acute urinary retention might be a clinical marker for occult urogenital, colorectal, and neurological cancers. Occult cancer should possibly be considered in patients aged 50 years or older presenting with acute urinary retention and no obvious underlying cause.

The Association between Mortality-to-Incidence Ratios and Health Expenditures in Brain and Nervous System Cancers

Mortality-to-incidence ratios (MIRs) are alternative parameters used to evaluate the prognosis of a disease. In addition, MIRs are associated with the ranking of health care systems and expenditures for certain types of cancer. However, a lack of association between MIRs and pancreatic cancer has been noted. Given the poor prognosis of brain and nervous system cancers, similar to pancreatic cancer, the relation of MIRs and health care disparities is worth investigating. We used the Spearman's rank correlation coefficient (CC) to analyze the correlation between the MIRs in brain and nervous system cancers and inter-country disparities, including expenditures on health and human development index. Interestingly, the MIRs in brain and nervous system cancers are associated with the human development index score (N = 157, CC = -0.394, p < 0.001), current health expenditure (CHE) per capita (N = 157, CC = -0.438, p < 0.001), and CHE as percentage of gross domestic product (N = 157, CC = -0.245, p = 0.002). In conclusion, the MIRs in the brain and nervous system cancer are significantly associated with health expenditures and human development index. However, their role as an indicator of health disparity warrants further investigation.

Association between parental occupational exposure to extremely low frequency magnetic fields and childhood nervous system tumors risk: A meta-analysis

BACKGROUND AND OBJECTIVE

Previous epidemiological studies suggested association between parental occupational exposure to extremely low frequency magnetic fields (ELF-MF) and risk of childhood nervous system tumors, but the results were inconsistent. We conducted a meta-analysis of case-control and cohort studies to re-evaluate this association.

METHODS

Relevant studies were identified by searching PubMed and Web of Science databases as well as by manual searching. Summary odds ratio (OR) with 95% confidence interval (CI) were pooled with a fixed-effects or random-effects model.

RESULTS

A total of 22 eligible articles (21 case-control studies and 1 cohort study) were included for the quantitative analysis. The results showed that parental occupational ELF-MF exposure was significantly associated with an increased risk of childhood nervous system tumors (OR = 1.11, 95% CI = 1.02-1.21), and this association remained in studies on central nervous system (CNS) tumors (OR = 1.13, 95% CI = 1.02-1.27) but not neuroblastoma (OR = 1.02, 95% CI = 0.92-1.14). Furthermore, maternal (OR = 1.14, 95% CI = 1.05-1.23) but not paternal (OR = 1.05, 95% CI = 0.98-1.13) occupational ELF-MF exposure significantly increased risk of childhood nervous system tumors. Increased risk of childhood CNS tumors was significant associated with maternal (OR = 1.16, 95% CI = 1.06-1.26) but not paternal (OR = 1.15, 95% CI = 0.98-1.34) occupational ELF-MF exposure.

CONCLUSION

In conclusion, our results provide limited evidence for the association between maternal occupational exposure to ELF-MF and increased risk of childhood CNS tumors, which should be explained with cautions. Future studies are needed to further evaluate the association of paternal occupational ELF-MF exposure with risk of childhood CNS tumors.

Exploration study on mortality trends in the territory surrounding an incineration plant of urban solid waste in the municipality of Vercelli (Piedmont, Italy) 1988-2009

BACKGROUND

The places, where the incinerators are located, often present problems of heterogeneous people having different environmental factors. It becomes important to evaluate the possible etiologic role of various environmental risk factors and try to quantify as they affect in the excess epidemiological.

METHODS

This study considers the ISTAT index mortality due to all causes occurred from 1988 to 2009 referred to ten municipalities at south of Vercelli (Piedmont, North Western Italy) placed nearby the active incinerator from 1977 (10 latent years). The risks were calculated considering this area at risk versus the municipalities placed at North of Vercelli and versus the Vercelli.

RESULTS

Some significant statically excesses emerged in the South area such as neoplasia of nervous system, liver and total of tumours.

CONCLUSIONS

The study presents some drawbacks, but it is a work creditable of widening by specific research ad hoc such as cohort and/or control where it is possible to verify various environmental, occupational and occasional factors.

[Incidence and mortality of brain tumor in areas with cancer registration of Zhejiang province, from 2000 to 2009]

OBJECTIVE

To investigate the incidence and mortality of brain tumor in Zhejiang cancer registration areas from 2000 to 2009.

METHODS

Data from 6 Cancer registration areas of Zhejiang province were collected. Number of cases, crude rates, proportions, age standardized rates, cumulate rates, cut rates, age-specific rates and annual percentage change (APC, 95% CI) of brain tumor incidence and mortality were analyzed.

RESULTS

There were 5 123 new diagnosed brain tumor cases in Zhejiang cancer registration areas, accounting for 3.14% of all the new cancer cases. The incidence rate of brain tumor was 8.53/100 000, and the standardized incidence rate by Chinese population was 5.72/100 000, ranking the 7th????? in cancer incidence spectrum of anatomic sites. Agespecific incidence of brain tumor increased along with age, and peaked among 70-74 age groups (24.09/100 000). The annual incidence rate of brain tumor increased from 2000 (6.87/100 000) to 2009(8.35/100 000), with APC as 1.58% (95%CI: -2.17%-5.47%, no statistical significance). A total of 2 357 deaths caused by brain tumor were reported from 2000-2009, accounting for 2.47% of all the cancer death cases. Mortality rate on brain tumor appeared to be 3.92/100 000, with the standardized mortality rate by Chinese population as 2.45/100 000, ranking the 7th????? in cancer mortality spectrum of anatomic sites. The age-specific mortality of brain tumor remained low among 0-39 year-olds, and reached the peak at 80-84 age groups (17.64/100 000). The annual mortality rate of brain tumor decreased from 2000(4.30/100 000)to 2009 (3.83/100 000) with minor fluctuation, and the APC was -0.65% (95%CI: -3.35%-2.12%, no statistical significance).

CONCLUSION

Brain tumors incidence and mortality in Zhejiang cancer registration areas were at a relatively high level. People who were at middle-age, especially above 70 years old should be the key targets for protection on this disease. Brain tumor incidence rates increased annually in Zhejiang, which should be called for attention.

Bone metastases and skeletal-related events in patients with malignant pheochromocytoma and sympathetic paraganglioma

CONTEXT

Bone metastases (BM) can cause severe pain, spinal cord compression, pathological fractures, and/or hypercalcemia. These skeletal-related events (SREs) may cause immobilization, loss of independence, poor quality of life, and reduced survival. There is limited information on the clinical effects of BM and SREs in patients with malignant pheochromocytoma or sympathetic paraganglioma (PHEO/sPGL).

OBJECTIVES

We studied the prevalence and clinical characteristics of BM and SREs in patients with PHEO/sPGL and investigated the risk factors for SRE development.

DESIGN

Using a large institutional database, we conducted a retrospective study of 128 patients with malignant PHEO/sPGL at The University of Texas MD Anderson Cancer Center from 1967 through 2011.

RESULTS

Of the patients, 91 (71%) had BM, and 57 of these (63%) developed metachronous BM at a median time of 3.4 years (range, 5 months to 23 years) after the primary tumor diagnosis. Metastatic disease was confined exclusively to the skeleton in 26 of 128 (20%) patients. Sufficient information to assess SRE occurrence was available for 67 patients, and 48 of 67 (72%) patients had at least 1 SRE. The median overall survival for the 128 patients was 12 years for patients with only BM, 7.5 years for patients with nonosseous metastases, and 5 years for patients with both BM and nonosseous metastases (log rank test P value = .005). We were unable to identify factors predictive of SRE development, but the occurrence of a first SRE was associated with the development of subsequent SREs in 48% of subjects. In responsive patients, the use of systemic therapy was associated with fewer SREs (P < .0001).

CONCLUSIONS

BM and SREs are frequent in patients with malignant PHEO/sPGL. SREs often develop shortly after the diagnosis of BM; severe pain is the most frequent SRE. These patients should be followed long-term by a multidisciplinary team to promptly identify the need for medical or surgical intervention.

[Estimates and prediction on incidence, mortality and prevalence of brain and neurologic tumors in China, 2008]

OBJECTIVE

To estimate the incidence, mortality and 5-year prevalence of brain and neurologic tumors in China, 2008.

METHODS

Data from 36 cancer registries in China and from the Third National Death Survey in China were used to estimate the incidence, mortality and 5-year prevalence of brain and neurologic tumors in 2008, using the mathematical models. Prediction on the incidence, and mortality of brain and neurologic tumors in the next 20 years was also carried out.

RESULTS

In 2008, the incidence of brain and neurologic tumors in China was 66 454 (2.4%) and the incidence rate of age-standardized was 4.4/100 000, ranking tenth among all the cancers. The mortality of brain and neurologic tumors in China was 45 573 (2.3%), with mortality rate as 3.0/100 000, which ranked seventh among all the cancers. The 5-year prevalence of brain and neurologic tumors in China was 91 449 (2.0%) and the proportion was 8.6/100 000, which ranked twelfth among all the cancers. Incidence rates of brain and neurologic tumors in all the age groups were similar in both sexes, but the rate of incidence increased faster before 40 years old and slowed down thereafter. In the next 20 years, data from the prediction showed that the incidence and mortality of brain and neurologic tumors in China would gradually increase.

CONCLUSION

The burden of brain and neurologic tumors was increasing continuously.

Space-time clustering in childhood nervous system tumors in the Region of Murcia, Spain, 1998-2009

AIMS

The aims of this study are the following: first, to analyze incidence, trends, and survival of nervous system tumors in children under the age of 15 in the Region of Murcia, Spain, during the years 1998-2009 and second, to evaluate if certain environmental exposures may be involved in the etiology of childhood nervous system tumors. The study was performed on the spatial and temporo-spatial distribution of the observed cases.

METHODS

The Environment and Pediatric Cancer in the Region of Murcia is an ongoing research project aimed at carefully collecting pediatric environmental history (PEH) and to use geographical information systems to map the incidence and to analyze the geographical distribution of pediatric cancer incidence in our region. Between 1998 and 2009, 125 patients were diagnosed with nervous system tumors. The spatial and temporal space clusters were evaluated using Kulldorff's statistics. Address at diagnosis was the main feature evaluated.

RESULTS

The incidence (cases/million children) for central nervous system (CNS) tumors was 34.2, that for sympathetic nervous system tumors was 10.9, and that for retinoblastoma was 1.9. There was evidence of space clustering for medulloblastoma and space-time clustering for all tumors, CNS tumors, astrocytoma, and neuroblastoma.

CONCLUSIONS

The incidence and survival for each type and subtype of nervous system tumors were within the reported values for the European region. There is evidence that spatial and spatial-temporal distribution in these cases is not random. The development of a careful PEH in these patients will help to reinforce geographical information system studies and to ascertain the importance of associated risk factors.

Increasing incidence of brain and nervous tumours in urban Shanghai, China, 1983-2007

BACKGROUND

Wide use of cellular telephones has given rise to concerns about adverse health effects, especially in the brain, which might caused by the low power microwave-frequency signal transmitted by the antennas on handsets. Subscribers to cellular telephone services increased from mid-1990s in Shanghai; time trends in brain and nervous tumour after 2000 may supply information about possible associations between tumour risk and cellular telephones use.

METHODS

We investigated time trends in the incidence of brain and nervous tumour in urban Shanghai, from 1983 to 2007, applying joinpoint regression models to analyze the annual incidence rates and to predict future trends.

RESULTS

from 1983 to 2007, the age-adjusted incidence rate of brain and nervous tumours increased gradually by 1.2% per year (95% confidence interval [CI] = 0.4% to 1.9%) among men and 2.8% per year (95% CI =2.1 to 3.4) among women. Age-adjusted incidences of brain and nervous tumours in urban Shanghai for 2020 were estimated to 7.4 and 10.9 per 100,000 person-years.

CONCLUSION

The study did not support an association between cellular telephone use and increased risk of brain and nervous tumours. However, considering the increasing incidence rate of brain and nervous tumours now and in the future, in addition to the high prevalence of mobile phone exposure in the population and worldwide, assessment of longer follow-up time trends in brain tumour incidence rates is warranted.

Estimation of cancer incidence and mortality attributable to smoking in China

BACKGROUND

Tobacco smoking, as a cause of cancer, is common in China. Few studies have been conducted to assess the burden of tobacco-related cancer in the Chinese population.

METHODS

We calculated the proportion of cancers attributable to tobacco smoking to estimate the burden of tobacco-related cancer. Population attributable fraction was calculated based on the assumption of total avoidance of smoking. Data on smoking prevalence were from two large-scale national surveys of representative samples of the Chinese population. Data on relative risk were derived from the meta-analyses and large-scale studies. Cancer mortality and incidence were originated from the third national death cause survey and cancer registries in China.

RESULTS

We estimated that a total of 405,112 deaths of cancer were attributable to smoking in China in 2005, including 372,264 among men (32.7% of all cancer deaths) and 32,848 among women (5.0%). A total of 495,221 cancer cases were attributable to smoking, including 454,785 among men (30.0% of all cancer cases) and 40,436 among women (3.9%). Involuntary smoking was responsible for 11,507 lung cancer deaths (11.1%) among non-smoking women.

CONCLUSION

Tobacco smoking is responsible for one-third of the total cancer deaths among men. Involuntary smoking is an important individual risk factor for lung cancer among non-smoking women. There is a need to continue and strengthen tobacco-control programs and initiatives to reduce smoking-related cancer burden in China.

Trends in survival of patients diagnosed with cancers of the brain and nervous system, thyroid, eye, bone, and soft tissues in the Nordic countries 1964-2003 followed up until the end of 2006

BACKGROUND

Diagnoses of cancer of the brain, thyroid, eye, bone, and soft tissues are categorised by heterogeneity in disease frequency, survival, aetiology and prospects for curative therapy. In this paper, temporal trends in patient survival in the Nordic countries are considered.

MATERIAL AND METHODS

Age-standardised incidence and mortality rates, 5-year relative survival, and excess mortality rates for varying follow-up periods are presented, as are age-specific 5-year relative survival by country, sex and 5-year diagnostic period.

RESULTS

Brain cancer incidence rates have been rising but mortality has been relatively stable, with 5-year survival uniformly increasing from the early-1970s, particularly in younger patients. Five-year survival from brain cancer among men varies between 45% and 50% for men and 60% to 70% in women, with excess deaths decreasing with time in each of the Nordic populations. Age-standardised incidence rates of thyroid cancer have been mainly increasing during the 1960s and 1970s, although trends thereafter diverge, with 5-year relative survival increasing 20-30 percentage points over the last 40 years to around 80-90%. Thyroid cancer survival is consistently lower in Denmark, particularly in patients diagnosed aged over 60, while there is less geographic variation in excess deaths three months beyond initial diagnosis. Relative survival from eye cancer increased with time from approximately 60% in 1964-1968 to 80% 1999-2003, while for bone sarcoma, incidence rates remained stable, mortality rates declined, and 5-year survival increased slightly to around 55-65%. Soft tissue sarcoma incidence and survival have been slowly increasing since the 1960s, with little variation in survival (around 65%) for the most recent period.

CONCLUSIONS

There have been some notable changes in survival that can be linked to epidemiological and clinical factors in different countries over time. Time-varying proportions of the major histological subtypes might however have affected the survival estimates for a number of the cancer forms reviewed here.

[Health evaluation of the population of the city of Trino Vercellese: epidemiological study on cancer incidence and mortality]

The study includes an analysis of the state of health of the inhabitants of the City of Trino, County of Vercelli, 15 km south-west of the capital town. With industries making a significant environmental impact and an old nuclear centre under dismantlement, in recent years, the City has often been mentioned in local newspapers and pressurised by residents and local associations. Hence the drawing up of this study to describe the state of health of residents and cancer pathologies (incidence and mortality rate) and, consequently, to evaluate the need for further epidemiological analysis. The rates (SIR and SMR) were obtained by calculating the expected results compared with those of the Local Health Authority of Vercelli and the Airtum registries of Northern Italy: the results (divided by sex) highlight significant excesses in neoplasias of the mouth, nervous system, peritoneum in addition to eukaemias and mesoteliomas. Furthermore, the analysis by age shows epidemiological anomalies both at paediatric (0-14 years) and young people (0-44 years) levels: these results certainly require further epidemiological research through aetiological studies, including an ad hoc questionnaire.

Endocrine manifestations of the rapid-onset obesity with hypoventilation, hypothalamic, autonomic dysregulation, and neural tumor syndrome in childhood

CONTEXT

Rapid-onset obesity with hypoventilation, hypothalamic, autonomic dysregulation, and neural tumor (ROHHADNET) is a newly described syndrome that can cause cardiorespiratory arrests and death. It mimics several endocrine disorders or genetic obesity syndromes during early childhood and is associated with various forms of hypothalamic-pituitary endocrine dysfunctions that have not yet been fully investigated.

OBJECTIVE

The current report aspires to facilitate the earlier recognition and appropriate treatment of the ROHHADNET syndrome when children present with various endocrine manifestations, such as early obesity, growth failure, pseudo-Cushing's syndrome, glucocorticoid insufficiency, congenital hypopituitarism, or adrenal tumors. A more widespread knowledge of the syndrome will help characterize its molecular origin.

DESIGN

Endocrine studies were performed in six patients admitted for seemingly common early-onset obesity associated with growth failure in five of them. The six patients later showed distinctive features of the ROHHADNET syndrome.

RESULTS

Abnormalities of the pituitary adrenal axis ranged from a true Cushing-like profile (one of six), to glucocorticoid deficiency with normal ACTH (two of six). Complete GH deficiency with low IGF-I was observed in four of six, hypogonadotropic hypogonadism in four of six, hyperprolactinemia in six of six, and various degrees of TSH/T(4) abnormalities in five of five patients. All had increased natremia without diabetes insipidus. Five children had unilateral macroscopic adrenal ganglioneuroma. Two patients died at 8.5 and 12 yr of age.

CONCLUSIONS

Various hypothalamic-pituitary endocrine dysfunctions are associated with ROHHADNET, carrying a risk of misdiagnosis until other elements of the syndrome make it more easily recognizable. Given its severity, ROHHADNET syndrome should be considered in all cases of isolated, rapid, and early obesity.

Epidemiology of genetically determined cancer

Dominantly heritable susceptibility is known for virtually every cancer. Susceptibility is typically restricted to one or a few tumours. For some tumours there appear to be at least two different predisposing conditions. Some mutant gene carriers survive to old age without developing the expected tumour(s). Some cases are new germline mutations. None of the conditions is very common, because of natural selection against gene carriers. Two questions arise: What is inherited? What is the relationship between the hereditary and non-hereditary forms of the same tumour? Retinoblastoma is a prototypic tumour. Penetrance in humans is nearly complete by the age of five years in the heritable form, which usually affects both eyes. Rare cases in which there is a constitutional deletion of chromosomal band 13q14 permitted localization of the responsible gene. Tumour formation is clearly a rare event at the cellular level, suggesting the necessity of a second, somatic, event. The difference in ages at diagnosis between unilateral and bilateral cases also suggests that two somatic events occur in non-hereditary cases. One explanation is that the gene is recessive and the second event involves loss of the remaining normal allele by mutation, non-disjunction, deletion or somatic recombination. The normal allele may be regarded as anti-oncogenic.

Exposure to pesticides and childhood cancer risk: has there been any progress in epidemiological studies?

OBJECTIVES

In Europe and the United States, cancer is a major cause of death among children aged 5-14 years. The role of environmental exposure to pesticides in carcinogenesis, although strongly postulated, is still unknown. Pesticides have been used since the early days of modern agriculture. They are biologically active compounds, which may pose health risk during or after their use.

MATERIALS AND METHODS

Epidemiological studies focused on childhood cancer and exposure to pesticides, conducted over the last seven years, were identified through searching PUBMED, MEDLINE and EBSCO literature bases. From each study, the following information was abstracted: type of cancer, type of exposure, study design, risk estimate, and study population. This review will try to answer the question on whether any further progress in epidemiology of childhood cancer due to pesticide exposure has been made.

RESULTS

Leukemia, brain cancer, non-Hodgkin's lymphoma and neuroblastoma are mentioned as potentially associated with pesticide exposure among children. Despite an increasing evidence in support of this finding, it is still limited because of the weakness of research methodology. The substantial weak points of numerous epidemiological studies of pesticide-related health effects are problems faced in exposure assessment, small numbers of exposed subjects, a limited number of studies focused on the majority of cancers, and difficulties in estimating critical windows of exposure.

CONCLUSION

In the light of existing, although still limited evidence of adverse effects of pesticide exposure, it is necessary to reduce exposure to pesticides. The literature review suggests a great need to increase awareness among people occupationally or environmentally exposed to pesticides about their potential negative influence on health of their children.

Incidence and familial risks in pituitary adenoma and associated tumors

Reliable data on familial risks are important for clinical counseling and cancer genetics. We wanted to study incidence trends and familial risks for pituitary adenomas and associated tumors through parental and sibling probands, using the nation-wide Swedish Family-Cancer Database on 10.5 million individuals, containing families with parents and offspring. Cancer data were retrieved from the Swedish Cancer Registry from years 1958 to 2002, including 3239 pituitary tumor patients. Familial risk for offspring was defined through standardized incidence ratio (SIR), adjusted for many variables. The incidence of pituitary adenoma has increased moderately from 1958 to the 1990s and declined thereafter. There were only three offspring-parent pairs with a concordant pituitary tumor, the SIR was not significant. Parental skin cancer (SIR 1.60) and leukemia (1.90, chronic lymphatic leukemia 2.59) were associated with offspring pituitary adenoma diagnosed at any age up to 70 years. There was a strong association of pituitary adenomas with nervous system hemangiopericytomas, SIR 182. The only significant association among siblings was between pituitary tumors and breast cancer (1.46). The risk of pituitary adenoma was marginally increased in individuals whose siblings were diagnosed with colorectal cancer. The results suggest an association of pituitary adenomas with nervous system hemangiopericytomas and breast and colorectal cancers, in addition to some other tumor types. Whether these associations can be explained by the recently identified pituitary adenoma predisposing gene, AIP, remains to be established.

Association between number of siblings and nervous system tumors suggests an infectious etiology

OBJECTIVE

To estimate the effect of the number of siblings on the risk of histopathologic subtypes of tumors of the nervous system using large population-based data.

METHODS

The Swedish Family-Cancer Database comprises 13,613 diagnoses of nervous system tumors with histopathologic information. We analyzed the data using Poisson regression models taking into account potential confounding effects of age, birth cohort, socioeconomic status, and family history of cancer.

RESULTS

The rate ratios (RR) for having four or more siblings vs none were significantly increased for hemangioblastoma (RR = 1.68), childhood neuroblastoma (RR = 2.01), and ependymoma (RR = 1.83, p trend < 0.01). For age at diagnosis < or =15 years, the RRs for individuals with three or more younger siblings compared to none were 1.34 for astrocytoma, 2.30 for medulloblastoma, 2.61 for ependymoma, 3.71 for meningioma, and 2.13 for neuroblastoma, with significant trends in risk. Non-significant decreased risks were found between the number of older siblings and nervous system tumors.

CONCLUSIONS

We provide the first reliable quantification of the effects of number of siblings on the risk of nervous system tumors. Sibship size and number of younger siblings correlate with the incidence of childhood nervous system tumors, suggesting a role of infectious agents in the etiology of the disease.

Adverse health effects of children's exposure to pesticides: what do we really know and what can be done about it

Children may be exposed to pesticides in several ways, such as by transplacental transfer during foetal life, by intake of contaminated breast milk and other nutrients, or by contact with contaminated subjects and areas in the environment such as pets treated with insecticides, house dust, carpets and chemically treated lawns and gardens. Exposure early in life, and particularly during periods of rapid development, such as during foetal life and infancy, may have severe effects on child health and development by elevating the risk of congenital malformations, cancer, malabsorption, immunological dysfunction, endocrine disease, and neurobehavioural deficiencies. As pesticides can also interfere with parental reproductive health, exposure of parents may have consequences for the offspring leading to reduced chance of male birth and increased risk of childhood cancer.

CONCLUSIONS

Current knowledge about tolerable levels and consequences of toxic exposure to pesticides during human development is rather scarce. Owing to the high risk of exposure to pesticides, particularly in less developed countries, further elucidation by well-controlled epidemiological studies in this field it is urgently needed. The Policy Interpretation Network on Children's Health and Environment (PINCHE), which is financed by the EU DG research has suggested actions against pesticide exposure. They have been presented and discussed in this paper. Several suggestions of PINCHE concerning action needed regarding pesticides were presented in the paper.

Are twins at risk of cancer: results from the Swedish family-cancer database

A few twin studies on cancer have addressed questions on the possible carcinogenic or protective effects of twining by comparing the occurrence of cancer in twins and singletons. The nationwide Swedish Family-Cancer Database of 10.2 million individuals and 69,654 0- to 70-year-old twin pairs were used to calculate standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) for all main cancers compared to singletons. The overall risk of cancer in same- or different-sex twins was at the same level as the risk for singletons. Testicular cancer, particularly seminoma, was increased among same-sex twins (1.54) and all twins to an SIR of 1.38. Among other tumors, neurinomas and non-thyroid endocrine gland tumors were increased. Colorectal cancers and leukemia were decreased among all twins. Melanoma and squamous cell skin cancer were decreased in male same-sex twins. The data on this unselected population of twins suggest that twinning per se is not a risk factor of cancer. In utero hormonal exposures or postnatal growth stimulation may be related to the risk of testicular cancer and pituitary tumors. Protective effects against colorectal cancer may be related to a beneficial diet, and in melanoma and skin cancer, to socioeconomic factors. The study involved multiple comparisons, and internal consistency between the results was one of the main factors considered for their plausibility. The results should encourage others working on twin and singleton populations to examine the specific associations and emerging hypotheses.

Primary Lymphoma of the Nervous System

This review article provides guidelines for the diagnosis, staging, and management of primary nervous system lymphoma based on the results of clinical trials conducted during the last decade. Recent progress in our understanding of the pathogenesis of primary nervous system lymphoma is summarized, and implications of these findings for the development of diagnostic tools and new therapeutic strategies are outlined. We performed a search of the PubMed database (National Center for Biotechnology Information) for articles on primary nervous system lymphoma published between 1970 and May 2005. Primary nervous system lymphoma affects the brain, eye, and meninges as well as cranial, spinal, and peripheral nerves. Although important lessons have been learned from the pathogenesis of extraneural non-Hodgkin's lymphoma, the unique organotropism of primary nervous system lymphoma remains poorly understood. Diagnosis is facilitated by modern imaging techniques and molecular markers. Clinically recognizable "precursors" may exist but frequently elude specific diagnosis. Insight into the peculiar pharmacokinetics of chemotherapy aimed at tumors within the nervous system has led to the development of methotrexate-based regimens that can achieve prolonged progression-free survival without the use of radiation. Long-term survival and, in selected cases, even a cure are possible in primary nervous system lymphoma. Treatment should be provided in specialized multidisciplinary centers. In spite of remarkable progress through methotrexate-based chemotherapy, the majority of patients experience relapse within a few years. Better diagnostic tools are required for earlier diagnosis and monitoring of treatment response. A deeper understanding of the pathogenesis of primary nervous system lymphoma may reveal new therapeutic targets.

[Shift and night work--is it a cancer risk factor?]

This paper presents the results of studies on the effects of circadian rhythm disturbances and melatonin on the carcinogenic process. It is thought that melatonin synthesis mostly influences the generation of breast and colorectal cancers. However, its influence on the development of prostate, ovarian, and endometriosis cancers is also suggested. It should be remembered that many other important risk factors contribute to the pathogenesis of these diseases. It is essential for occupational medicine physicians to pay special attention to so called "oncological risk" in workers with long duration of employment in the shift-work system as this group of workers is also exposed to other cancer risk factors. Exogenous melatonin supplementation along with reduced effect of shift work is very important from the practical point of view.

Causation of nervous system tumors in children: insights from traditional and genetically engineered animal models

Pediatric neurogenic tumors include primitive neuroectodermal tumors (PNETs), especially medulloblastoma; ependymomas and choroid plexus papillomas; astrocytomas; retinoblastoma; and sympathetic neuroblastoma. Meningiomas and nerve sheath tumors, although uncommon in childhood, are also significant because they can result from exposures of children to ionizing radiation. Specific chromosomal loci and specific genes are related to each of these tumor types. Virtually all these genes appear to act as tumor suppressor genes, which are inactivated in tumor cells by mutations or by chromosomal loss. In genetically engineered mice, some genes that are clearly associated with specific human tumors (e.g., RB1 in retinoblastoma and NF2 in meningiomas and schwannomas) have no such effect. Other genetic constructs in mice involving the genes p53, ptc1, and Nf1 have produced tumors remarkably similar to some of the human pediatric neoplasms. Some of these tumors become clinically apparent after only a few weeks, while the mice are still juveniles, especially when two or more tumor suppressor genes are inactivated in the same genetic construct. Conversely, at least one genetic pathway in rodents involving point mutation in the coding region of a transforming gene (neu in malignant schwannomas) does not appear to operate in any human tumors. The nervous system is markedly susceptible to experimental carcinogenesis during early life in rodents, dogs, primates, and other nonhuman species, and there is no obvious reason why this generalization should not also apply to humans. However, except for therapeutic ionizing radiation, no physical, chemical, or biological cause of human pediatric nervous system tumors is known. The failure of experimental transplacental carcinogenesis to mirror human pediatric experience more closely may reflect the need for multiple mutational events in target cells, and for experimental carcinogens that are capable of causing the full spectrum of mutations that occur in cancer-related genes in pediatric neurogenic tumors.

Poliovirus vaccination during pregnancy, maternal seroconversion to simian virus 40, and risk of childhood cancer

Before 1963, poliovirus vaccine produced in the United States was contaminated with simian virus 40 (SV40), which causes cancer in animals. To examine whether early-life SV40 infection can cause human cancer, the authors studied 54,796 children enrolled in the US-based Collaborative Perinatal Project (CPP) in 1959-1966, 52 of whom developed cancer by their eighth birthday. Those children whose mothers had received pre-1963 poliovirus vaccine during pregnancy (22.5% of the children) had an increased incidence of neural tumors (hazard ratio = 2.6, 95% confidence interval: 1.0, 6.7; 18 cases) and hematologic malignancies (hazard ratio = 2.8, 95% confidence interval: 1.2, 6.4; 22 cases). For 50 CPP children with cancer and 200 CPP control children, the authors tested paired maternal serum samples from pregnancy for SV40 antibodies using a virus-like particle enzyme immunoassay and a plaque neutralization assay. Overall, mothers exhibited infrequent, low-level SV40 antibody reactivity, and only six case mothers seroconverted by either assay. Using the two SV40 assays, maternal SV40 seroconversion during pregnancy was not consistently related to children's case/control status or mothers' receipt of pre-1963 vaccine. The authors conclude that an increased cancer risk in CPP children whose mothers received pre-1963 poliovirus vaccine was unlikely to have been due to SV40 infection transmitted from mothers to their children.

Clinical-histopathologic concordance of tumors of the nervous system at the Manuel Velasco Suárez National Institute of Neurology and Neurosurgery in Mexico City

CONTEXT

When making a diagnosis, the main purpose of clinicians should not be to achieve certainty, but to decrease diagnostic uncertainty in order to make optimal therapeutic decisions. Diagnostic concordance is an essential characteristic if a measurement is to be considered scientific. In the case of tumors of the nervous system (TNS), one of the most accurate diagnostic tests is magnetic resonance imaging. However, histopathologic analyses are essential, because they refine the diagnosis, benefit the patient, and improve our understanding of the disease. By determining the clinical-histopathologic correlation of TNS in one of the main neurologic centers in Mexico, we sought to project reliable morbidity and/or mortality statistics.

OBJECTIVE

To assess clinical and histopathologic diagnostic agreement in cases involving TNS admitted to the Manuel Velasco Suárez National Institute of Neurology and Neurosurgery between 1990 and 1999.

DESIGN

Cross-sectional diagnostic concordance study, including all clinical hospital records of patients with histopathologically diagnosed TNS, classified according to World Health Organization criteria.

RESULTS

Among 2041 TNS cases, the 3 most frequent types were those affecting the neuroepithelial tissue (32.9%), tumors of the sellar region (29.2%), and tumors of the meninges (25.6%). We found that, overall, clinical-histopathologic concordance for these 3 categories was substantial and statistically significant.

CONCLUSIONS

Tumors of the nervous system constitute a heterogeneous group of neoplasms. In the present study, clinical diagnoses substantially agreed with pathologic diagnoses. The a priori clinical diagnosis allowed prompt treatment even before diagnostic confirmation by histopathologic analysis, which is the best way to confirm, clarify, and correct a diagnosis.

Tumors of the nervous system and pituitary gland associated with atomic bomb radiation exposure

BACKGROUND

The risk of developing nervous system tumors following exposure to ionizing radiation is not well quantified. We characterized the incidence of nervous system tumors among atomic bomb survivors as a function of radiation dose.

METHODS

Tumors of the nervous system and pituitary gland diagnosed between 1958 and 1995 among 80 160 atomic bomb survivors were ascertained using the Hiroshima and Nagasaki tumor registries, medical records, and death certificates. Pathologists reviewed slides and medical records to provide histologic diagnoses. Poisson regression analyses were used to characterize radiation effects on tumor incidence, which are expressed as excess relative risk per sievert (ERR(Sv)). All statistical tests were two-sided.

RESULTS

A statistically significant dose-related excess of nervous system tumors was observed in the cohort (ERR(Sv) = 1.2, 95% confidence interval [CI] = 0.6 to 2.1). The highest ERR(Sv) was seen for schwannoma (4.5, 95% CI = 1.9 to 9.2). The risk for all other nervous system tumors as a group is also statistically significantly elevated (ERR(Sv) = 0.6, 95% CI = 0.1 to 1.3). Risk increases, although not statistically significant, were seen for meningiomas (ERR(Sv) = 0.6, 95% CI = -0.01 to 1.8), gliomas (ERR(Sv) = 0.6, 95% CI = -0.2 to 2.0), other nervous system tumors (ERR(Sv) = 0.5, 95% CI = <-0.2 to 2.2), and pituitary tumors (ERR(Sv) = 1.0, 95% CI = <-0.2 to 3.5). The dose-response relationships were linear. For nervous system tumors other than schwannoma, excess risks were higher for men than for women and for those exposed during childhood than for those exposed during adulthood.

CONCLUSIONS

A statistically significant dose response was observed for all nervous system tumors combined and for schwannoma considered separately, indicating that exposure to even moderate doses (i.e., <1 Sv) of radiation is associated with an elevated incidence of nervous system tumors.

Cancer of the brain and nervous system and occupational exposures in Finnish women

Occupational agents were evaluated for the risk of brain-nervous system cancer in a cohort of 413,877 Finnish women with blue-collar occupations in 1970. Observed and expected numbers of incident cases and the intensities of exposure to 25 agents were generated for 183 job titles from 1971 to 1995. Poisson regression models linked incidence and exposure data. Increased risks were found for medium/high intensities of iron (standardized incidence ratio [SIR], 2.15; 95% confidence interval [CI], 0.96 to 4.80), oil mist (1.95; 0.97 to 3.90), any chromium compounds (1.51; 0.85 to 2.67), electromagnetic fields (1.37; 0.98 to 2.10), aliphatic and alicyclic hydrocarbon compounds (1.34; 0.80 to 2.27), lead (1.27; 0.81 to 2.01), cadmium (1.26; 0.72 to 2.22), and aromatic hydrocarbon compounds (1.20; 0.71 to 2.03). Strengths of the study include fair number of cases, virtually complete case coverage, and a high-quality job exposure matrix. Ecological design and cross-sectional job assessment introduced exposure misclassification and tended to drive risk estimates toward unity.

Cancer risks in childhood and adolescence among the offspring of immigrants to Sweden

We used the nation-wide Swedish Family-Cancer Database to analyse the risk of nervous system tumours, leukaemia and non-Hodgkin's lymphoma in age groups 0-4 and 0-19 years among Swedish-born offspring of immigrants. The study included 850 000 individuals with an immigrant background, including European, Asian and American parents. We calculated standardised incidence ratios for the above three malignancies using Swedish offspring as a reference. Subjects were grouped by region or by selected countries of parental origin. No group differed significantly from Swedes in the occurrence of nervous system neoplasm or leukaemia. Offspring of Yugoslav fathers (SIR 2.27) and Turkish parents were at increased risk of non-Hodgkin's lymphoma. The highest risk was noted for non-Hodgkin's lymphoma among young offspring (0-4 years) of two Turkish parents (6.87). The currently available limited data on rates for childhood non-Hodgkin's lymphoma in these countries do not explain the risk in the offspring of immigrants. Yugoslavs and Turks are recent immigrant groups to Sweden, and their offspring have been subject to much population mixing, perhaps leading to recurring infections and immunological stimulation, which may contribute to their excess of lymphomas.

Central nervous system tumors in Morocco. Retrospective analysis of 2374 cases

BACKGROUND

No epidemiological data about central nervous system tumors in Morroco have been published. The objective of the present study is to assess topographic and demographic patterns of a large series of histologically confirmed tumors of central nervous system (CNS), skull and vertebral column, examined in the main neuropathology laboratory of the country.

METHODS

No. 2363 tumors have been collected in the department of Neuropathology in Hôpital des spécialités oto-neuro-ophtalmiques, Rabat, between 1988 and 1997. Data concerning age, sex, tumor location and histological type were retrieved from the laboratory files. Histological typing was based on the World Health Organization (WHO) classification of central nervous system tumors and grading on the Kernohan and Mayo Clinic-St. Anne systems.

RESULTS

No. 1454 intraparenchymatous and 904 extraparenchymatous tumors were studied. The topographic repartition of these tumors presented no differences when compared to the literature data. The main differences were noted for malignant astrocytomas and glioblastomas which were less frequent than in Western countries and occurred in younger people. The young age of Morrocan population probably explains these findings. Childhood tumors repartition was similar to Western series.

CONCLUSIONS

These results emphazise the need for a population based registry in order to verify our findings and adapt efficient health intervention.

Primary nervous-system lymphoma

Primary nervous-system lymphoma is a rare type of non-Hodgkin lymphoma, which is confined to the nervous system. This disease is managed quite differently from the usual treatment of either primary brain tumours or systemic non-Hodgkin lymphoma. Although whole-brain radiotherapy results in responses in more than 90% of cases, this treatment is associated with high relapse rates and with delayed neurotoxicity in elderly patients. First-generation chemotherapy regimens used successfully in systemic non-Hodgkin lymphoma (eg cyclo-phosphamide, adriamycin, vincristine, and prednisone) are ineffective in primary nervous-system lymphoma, partly because of the blood-brain barrier. Median survival of patients treated with radiotherapy alone or chemotherapy plus radiotherapy is similar, and ranges from 10 to 16 months. The addition of methotrexate-based chemotherapy has improved survival for these patients, extending median survival to more than 30 months. When used alone, methotrexate-based chemotherapy is associated with significantly fewer treatment-associated toxic effects. Leptomeningeal lymphoma and intraocular lymphoma are topics of particular relevance in primary nervous-system lymphoma and are addressed in this review.

Cellular telephones and cancer--a nationwide cohort study in Denmark

BACKGROUND

Use of cellular telephones is increasing exponentially and has become part of everyday life. Concerns about possible carcinogenic effects of radiofrequency signals have been raised, although they are based on limited scientific evidence.

METHODS

A retrospective cohort study of cancer incidence was conducted in Denmark of all users of cellular telephones during the period from 1982 through 1995. Subscriber lists from the two Danish operating companies identified 420 095 cellular telephone users. Cancer incidence was determined by linkage with the Danish Cancer Registry. All statistical tests are two-sided.

RESULTS

Overall, 3391 cancers were observed with 3825 expected, yielding a significantly decreased standardized incidence ratio (SIR) of 0.89 (95% confidence interval [CI] = 0.86 to 0.92). A substantial proportion of this decreased risk was attributed to deficits of lung cancer and other smoking-related cancers. No excesses were observed for cancers of the brain or nervous system (SIR = 0.95; 95% CI = 0.81 to 1.12) or of the salivary gland (SIR = 0.72; 95% CI = 0.29 to 1.49) or for leukemia (SIR = 0.97; 95% CI = 0.78-1.21), cancers of a priori interest. Risk for these cancers also did not vary by duration of cellular telephone use, time since first subscription, age at first subscription, or type of cellular telephone (analogue or digital). Analysis of brain and nervous system tumors showed no statistically significant SIRs for any subtype or anatomic location.

CONCLUSIONS

The results of this investigation, the first nationwide cancer incidence study of cellular phone users, do not support the hypothesis of an association between use of these telephones and tumors of the brain or salivary gland, leukemia, or other cancers.

Paternal occupational exposures and childhood cancer

The objective of the study described here was to test the hypothesis that paternal occupational exposure near conception increases the risk of cancer in the offspring. We conducted a cohort study based on a population of 235,635 children born shortly after two different censuses in Sweden. The children were followed from birth to 14 years, and cases of cancer were identified in the Swedish Cancer Registry. Occupational hygienists assessed the probability of exposure to different agents in each combination of the father's industry and occupation as reported in the censuses. We also analyzed individual job titles. We compared the cancer incidence among children of exposed fathers to that among children of unexposed fathers using Cox proportional hazards modeling. The main findings were an increased risk of nervous system tumors related to paternal occupational exposure to pesticides [relative risk (RR) = 2.36; 95% confidence interval (CI), 1.27-4.39] and work as a painter (RR = 3.65; 95% CI, 1.71-7.80), and an increased risk of leukemia related to wood work by fathers (RR = 2.18; 95% CI, 1.26-3.78). We found no associations between childhood leukemia and paternal exposure to pesticides or paint. Our results support previous findings of an increased risk of childhood brain tumors and leukemia associated with certain paternal occupational exposures. Some findings in previous studies were not confirmed in this study.

Occupation and adult gliomas

Lifetime job histories from a population-based, case-control study of gliomas diagnosed among adults in the San Francisco Bay area between August 1991 and April 1994 were evaluated to assess occupational risk factors. Occupational data for 476 cases and 462 controls were analyzed, with adjustment for age, gender, education, and race. Imprecise increased risks were observed for physicians and surgeons (odds ratio (OR) = 3.5, 95% confidence interval (CI): 0.7, 17.6), artists (OR = 1.9, 95% CI: 0.5, 6.5), foundry and smelter workers (OR = 2.6, 95% CI: 0.5, 13.1), petroleum and gas workers (OR = 4.9, 95% CI: 0.6, 42.2), and painters (OR = 1.6, 95% CI: 0.5, 4.9). Legal and social service workers, shippers, janitors, motor vehicle operators, and aircraft operators had increased odds ratios only with longer duration of employment. Physicians and surgeons, foundry and smelter workers, petroleum and gas workers, and painters showed increased risk for both astrocytic and nonastrocytic tumors. Artists and firemen had increased risk for astrocytic tumors only, while messengers, textile workers, aircraft operators, and vehicle manufacturing workers showed increased risk only for nonastrocytic tumors. Despite study limitations, including small numbers for many of the occupational groups, a high percentage of proxy respondents among cases, and lack of specific exposure information, associations were observed for several occupations previously reported to be at higher risk for brain tumors generally and gliomas specifically.

Primary mediastinal malignancies in children: report of 22 patients and comparison to 197 adults

PURPOSE

Examine a contemporary series of patients with primary pediatric malignant mediastinal tumors and determine epidemiology, histology, treatment, and survival. Patients and Methods. All malignancies diagnosed between January 1, 1973 and December 31, 1995 were analyzed.

RESULTS

Twenty-two patients, age 18 years or less, with pediatric primary mediastinal malignancies were identified from a database of 110,284 patients with primary malignancies. During the same period, 197 adult patients with primary mediastinal malignancies were identified. Fifty-nine percent of the pediatric patients were male. Median age was 11 years. Lymphoma was present in 55%, neurogenic malignancies in 23%, malignant germ cell tumors in 18%, and sarcoma in 5%. Neurogenic tumors presented in infants and lymphomas and germ cell tumors presented in teens (p = 0.005). In treated children, surgery was used more often in neurogenic tumors and germ cell tumors than in lymphomas (p = 0.002). Five-year survival was 74% for lymphomas, 67% for neurogenic tumors, 25% for germ cell tumors, and 61% overall (p = 0.23). Compared to adults, children had more neurogenic tumors (p < 0.001) and fewer thymomas (p = 0.0499). There were no significant differences in staging or survival between children and adults.

CONCLUSIONS

Pediatric mediastinal malignancies occurred with a frequency of 1/5,013 patients with malignant tumors. Lymphoma, neurogenic tumors, and germ cell tumors predominated. Compared to adults, children had more neurogenic tumors and fewer thymomas. Within the pediatric group, differences were found in age of presentation between histologic groups. These differences between adults and children, and between infants and teens, should be considered when evaluating a patient suspected of having mediastinal malignancy.

Evaluation of ENU-induced gliomas in rats: nomenclature, immunochemistry, and malignancy

Rats developed mixed gliomas, oligodendrogliomas, and a few astrocytomas in response to transplacental ethylnitrosourea. The neoplastic cell composition of mixed gliomas must be defined; this study required a 20-80% admixture of neoplastic astrocytes and oligodendroglia for the diagnosis of mixed glioma. A battery of immunoantibodies, including Leu-7, S-100, and vimentin, were helpful in classifying rat gliomas, and the histologic features of each tumor type are described. Other brain tumor characteristics that may decide the outcome of carcinogenicity studies include incidence, multiplicity, latency, fatality, size, and malignancy. The size of tumors was determined by measuring their 3-dimensional volumes. Brain tumor volume was found to be highly correlated with malignancy and fatality. Systematic evaluation of the malignancy of brain tumors is an important but often overlooked adjunct method of measuring the effectiveness of a carcinogen. A system to estimate malignancy, one that grades 9 tumor characteristics and weights, each according to clinical outcome, was developed. It was found that mixed gliomas grew larger, had a shorter latency, and were significantly more malignant than were other gliomas.

Parental age and risk of sporadic and familial cancer in offspring: implications for germ cell mutagenesis

We used the nationwide Swedish Family-Cancer Database to analyze the effect of parental age on cancer in offspring at ages 15-53 years. We studied 13 cancer sites, including 37,877 people. Data on familial and sporadic cancers were analyzed separately. We adjusted for age of spouse, year of diagnosis, and birth order. Rate ratios (RRs) were calculated by Poisson regression. Maternal age was associated with sporadic melanoma and leukemia, causing a 30% excess if mothers were more than 40 years vs. less than 20 years of age. A marginal effect of about 10% of both maternal and paternal age was observed for sporadic breast cancer. Paternal age increased the RR of sporadic nervous system cancer by about 15%. Accumulation of chromosomal aberrations and mutations during the maturation of germ cells may be a mechanism for these findings. In familial cancers of colon, melanoma, and thyroid, higher age showed an apparent protective effect, which was also noted for sporadic cervical cancer and melanoma. The results argue against major age-induced mutagenic/carcinogenic effects on germ cells as well as against age-induced adverse cancer-related hormonal effects during pregnancy. Because two or more mutations are required for adult cancers, however, these cancers may be an insensitive indicator of germ cell mutagenesis.

Lymphoma at uncommon sites

Lymphoma can often present in unusual situations. This article provides a comprehensive review of the literature in which both non-Hodgkin's lymphoma and Hodgkin's disease are discussed.

Cancer incidence, morbidity and geothermal air pollution in Rotorua, New Zealand

BACKGROUND

The New Zealand city of Rotorua sits on a geothermal field. However, little is known about the possible health impacts of the geothermal emissions. This was an ecological study that examined cancer incidence and morbidity data for Rotorua.

METHODS

Cancer registry and hospital discharge (morbidity) data were obtained for the decade 1981-1990. Standardized incidence ratios (SIR) were calculated comparing Rotorua residents with those living in the rest of New Zealand. Diagnostic categories examined were based on known target organ systems of hydrogen sulphide toxicity.

RESULTS

Of the cancer sites, there was an elevated rate for nasal cancers. However, this was based on only four cases. The SIR for cancers of the trachea, bronchus and lung in Maori women was 1.48 (95% CI: 1.03-2.06). This was not explained by higher smoking rates. In the hospital discharge data, a number of diseases showed elevated SIR, notably diseases of the nervous system and the eye. To some extent, these effects were characteristic of effects induced by hydrogen sulphide and also mercury compounds. However, there were few data with which to assess whether significant mercury exposures had occurred, and other explanations were possible.

CONCLUSIONS

There are inadequate exposure data for Rotorua to permit conclusions on likely causal associations. However, some of the elevated disease rates were at least consistent with what one might expect to find if sufficient exposures to hydrogen sulphide and/or mercury were occurring.

[Epidemiological and classification aspects of nervous system tumors]

The data obtained from various surveys of the epidemiology of the CNS tumors in different countries were analyzed. It was noted, the incidence of primary CNS tumors remains within the limits of 5-12.5 cases per 100,000 people, and depends on number of factors (e.g. sex, age, place of residence, etc.). Metastases double the incidence of all CNS tumors. The estimated incidence of tumors of the nervous system in Russia and particularly Moscow are given in the paper. The analysis of the data cells for the improvement in the organization of the medical care of this group of patients. With this respect the second WHO histological classification of CNS tumors (WHO, 1993) is critically analyzed. Based on the experience at the Burdenko Neurosurgical Institute (over 10,000 brain biopsies), a modified WHO neuropathological classification is suggested. The classification may be useful in research projects, and may facilitate the diagnosis, treatment, rehabilitation, and final assessment of the outcome. Series of documents of this kind help to make the evaluation of the activities of neurosurgical departments more objective, as well as to make the statistics more reliable.

Perineural invasion in transitional cell carcinoma and the effect on prognosis following radical cystectomy

OBJECTIVES

The relationship between perineural invasion and prognosis has been demonstrated to be poor in a number of malignancies. This has not been evaluated in the bladder. We performed a study to determine the occurrence of nodal metastases, extranodal metastases, and disease-free survival in patients with perineural invasion (PNI) and/or angiolymphatic invasion (ALI) in transitional cell carcinoma of the bladder (TCCB) from radical cystectomy specimens.

METHODS

A retrospective review of 27 patients treated with radical cystectomy for TCCB was conducted. Comparisons were performed between three groups: PNI with or without ALI (PNI +/- ALI, 12 patients), ALI alone (8 patients), and a control group (no PNI or ALI) (7 patients).

RESULTS

The mean patient age was 70 years (range 49 to 83). The overall median follow-up period was 11 months (range 1 to 32). PNI +/- ALI was predominantly found in Stage T3b disease (14 of 20 [70%] cases). The overall 1-year disease-free survival was 48%, 67%, and 83% for the PNI +/- ALI, ALI alone, and control groups, respectively. Nodal metastases (for all stages combined) were found in 6 of 12 (50%), 3 of 8 (38%), and 1 of 7 (14%) patients in the PNI +/- ALI, ALI alone, and control groups, respectively. Similarly, extranodal metastatic disease was found in 5 of 12 (42%), 4 of 8 (50%), and 1 of 7 (14%) patients in the PNI +/- ALI, ALI alone, and control groups, respectively. The percentage of deaths for the PNI +/- ALI, ALI only, and control groups were 33%, 50%, and 14%, respectively.

CONCLUSIONS

In TCCB, perineural invasion with or without angiolymphatic invasion and angiolymphatic invasion alone are associated with a higher incidence of nodal and extranodal metastases and death.

Magnetic fields of high voltage power lines and risk of cancer in Finnish adults: nationwide cohort study

OBJECTIVE

To investigate the risk of cancer in association with magnetic fields in Finnish adults living close to high voltage power lines.

DESIGN

Nationwide cohort study.

SUBJECTS

383,700 people who lived during 1970-89 within 500 metres of overhead power lines of 110-400 kV in a magnetic field calculated to be > or = 0.01 microT. Study subjects were identified by record linkages of nationwide registers.

MAIN OUTCOME MEASURES

Numbers of observed and expected cases of cancer, standardised incidence ratios, and incidence rate ratios adjusted for sex, age, calendar year, and social class--for example, by continuous cumulative exposure per 1 microT year with 95% confidence intervals from multiplicative models for all cancers combined and 21 selected types.

RESULTS

Altogether 8415 cases of cancer were observed (standardised incidence ratio 0.98; 95% confidence interval 0.96 to 1.00) in adults. All incidence rate ratios for both sexes combined were non-significant and between 0.91 and 1.11. Significant excesses were observed in multiple myeloma in men (incidence rate ratio 1.22) and in colon cancer in women (1.16).

CONCLUSIONS

Typical residential magnetic fields generated by high voltage power lines do not seem to be related to the risk of overall cancer in adults. The previously suggested associations between extremely low frequency magnetic fields and tumours of the nervous system, lymphoma, and leukaemia in adults and breast cancer in women were not confirmed.

Neurologic disorders in 203 consecutive patients with small cell lung cancer. Results of a longitudinal study

BACKGROUND

Neurologic complications of small cell lung cancer (SCLC) are manifold. The incidence and course of the various metastatic and nonmetastatic neurologic disorders were studied prospectively in a cohort of SCLC patients.

METHODS

The 203 patients underwent neurologic examinations on a regular basis, prior to therapy, during and after treatment, from 1983 through 1994. Routine computer tomography or magnetic resonance imaging of the brain was performed before therapy and after 2 years' survival. Other auxiliary diagnostic tests were performed as required.

RESULTS

The majority of the 174 neurologic disorders, diagnosed in 132 patients, were associated with metastases. A total of 79 patients developed brain metastases. The cumulative risk of brain metastases reached 47% for limited and 69% for extensive disease patients at 2 years from diagnosis. Survival following the diagnosis of brain metastases was significantly longer for patients with brain metastases at the initial diagnosis of SCLC than for patients with delayed brain metastases (P < 0.01, long rank test). The most frequent paraneoplastic syndrome with neurologic symptoms was that of inappropriate secretion of antidiuretic hormone (SIADH), which was diagnosed in 11 patients. Antibody-mediated paraneoplastic neurologic syndromes were diagnosed in five patients. Chemotherapy for SCLC caused SIADH to subside in most patients. In contrast, the antibody-mediated syndromes did not respond to SCLC therapy. Adverse effects of treatment included peripheral neuropathy, encephalopathy, radiation plexopathy, and steroid myopathy. However, unlike the other complications, peripheral neuropathy was reversible.

CONCLUSIONS

This clinical investigation confirmed the frequency of central nervous system metastatic involvement as well as the diversity of the neurologic complications in SCLC. The high frequency of brain metastases justifies a reappraisal of prophylactic cranial irradiation in this patient group.

Second primary cancers in patients with cutaneous malignant melanoma: a population-based study in Sweden

To quantify the risk of second primary cancers among patients with cutaneous malignant melanoma, we studied 20,354 patients in the Swedish Cancer Register during 1958-88. A second primary cancer was reported in 1605 patients, compared with an expected number of 1109.5 [standardised incidence ratio (SIR) = 1.45, 95% confidence interval (CI) = 1.38-1.52]. The highest risk was found among patients younger than 60 years. The greatest risk was seen during the first year after diagnosis (SIR = 1.91, CI = 1.69-2.14), but even after long-term follow-up--15 years or more--the risk was still significantly elevated (SIR = 1.56, CI = 1.35-1.79). The strongest association was found for a second primary malignant melanoma (men, SIR = 10.0, CI = 8.26-12.00; women, SIR = 8.66, CI = 7.22-10.30) and non-melanoma skin cancer (men, SIR = 3.58, CI = 2.85-4.44; women, SIR = 2.41, CI = 1.71-3.29). The risk of second cancers associated with tissues of neuroectodermal origin was increased, especially tumours of the nervous system (men, SIR = 1.73, CI = 1.10-2.60; women, SIR = 2.03, CI = 1.45-2.78). The SIR of second cancers involving the immune system was also increased. An excess risk of endometrial cancer was seen (SIR = 1.41, CI = 1.03-1.88), but no significant associations existed for cancers of the breast, ovary, testis or other endocrine glands. Among tumours of the digestive tract, only colon cancer in men had a significantly increased SIR (1.33, CI = 1.00-1.74).