Occupation and cancer – follow-up of 15 million people in five Nordic countries

Potassium octatitanate fibers (TISMO) induce pleural mesothelial cell reactions with iron accumulation in female A/J mice

It is crucial to develop therapeutic approaches for malignant mesothelioma, as well as to obtain information involving the possible mechanism involved in the development of mesothelioma. Subsequently, thoracotomy was performed to infuse test particles directly into the thoracic cavity of A/J mice. Fiber-shaped particles of potassium octatitanate (TISMO) and granular-shaped micro- and nano-size order particles of titanium dioxide (TiO(2)) were employed (1.5 mg in 0.2 ml saline/mouse). The experiment was terminated after 21 weeks to assess responses. Only the fiber-shaped TISMO, morphologically similar to asbestos, induced a severe reaction of the pleura. A number of TISMO fibers were observed in the alveoli, indicating penetration through the pleura. Following Berlin blue staining, positive spots were observed around the TISMO fibers, indicative of iron. These positive spots corresponded with cells that immunostained positively for calretinin, a marker of mesothelial cells. Similar observations were reported for asbestos-induced mesothelioma. The present study showed that only fiber-shaped TISMO induced severe reactions of the mesothelium in the pleura, and these involved iron accumulation derived from endogenous sources. The results indicate that the risk of mesothelial cell reaction does not depend on particle size, but may depend on shape.

Pulmonary nodules in workers exposed to urban stressor

By multilayer spiral low-dose computed tomography (LD-CT) of the chest this study assesses the early detection of lung lesions on a sample of 100 traffic policemen of a big Italian city professionally exposed to urban pollutants and 100 controls non-occupationally exposed to urban pollutants matched by sex, age, length of service and cigarette smoking habit. Exposure to urban pollutants in traffic policemen was characterized using the annual average concentrations of PM(10), NO2 and benzene in the period 1998-2008 measured by fixed monitoring stations located in different areas of the city. A significant and increasing number of suspicious lung nodules with diameters between 5 and 10 mm was observed: in traffic policemen (including smokers and non-smokers) vs. controls (including smokers and non-smokers); in total smokers (including traffic policemen and controls) vs. total non-smokers (traffic policemen and controls); in smoker traffic policemen vs. smoker controls and vs. non-smoker traffic policemen; in non-smoker traffic policemen vs. non-smoker controls. The RR of finding cases with at least one lung nodule with diameters between 5 and 10mm in traffic policemen (including smokers and non-smokers) compared to controls (including smokers and non-smokers) is 1.94 (CI 1.13-3.31); in total smokers vs. non-smokers the RR is 1.96 (CI 1.20-3.19). The comparison between the interaction exposure and smoking shows an increase in smoker traffic policemen than in smoker controls (RR=2.14; CI 1.02-4.52). The RR for smoker traffic policemen was higher than in non-smoker traffic policemen (RR=2.09; CI 1.19-3.66). The results of our study show that: (1) while smoker workers have a higher risk for developing solid suspicious lung nodules, the simple routinely exposure to urban pollutants is unable to produce the same kind of increased risk; (2) the interaction of smoking and exposure to urban pollutants greatly increases the risk for the development of solid suspicious lung nodules. In conclusion, the use of chest LD-CT in workers at risk helps identify suspicious solid lung nodules at early stage.

An eight-year snapshot of geospatial cancer research (2002-2009): clinico-epidemiological and methodological findings and trends

Geographic information systems (GIS) offer a very rich toolbox of methods and technologies, and powerful research tools that extend far beyond the mere production of maps, making it possible to cross-link and study the complex interaction of disease data and factors originating from a wide range of disparate sources. Despite their potential indispensable role in cancer prevention and control programmes, GIS are underrepresented in specialised oncology literature. The latter has provided an impetus for the current review. The review provides an eight-year snapshot of geospatial cancer research in peer-reviewed literature (2002-2009), presenting the clinico-epidemiological and methodological findings and trends in the covered corpus (93 papers). The authors concluded that understanding the relationship between location and cancer/cancer care services can play a crucial role in disease control and prevention, and in better service planning, and appropriate resource utilisation. Nevertheless, there are still barriers that hinder the wide-scale adoption of GIS and related technologies in everyday oncology practice.

Trends in the survival of patients diagnosed with kidney or urinary bladder cancer in the Nordic countries 1964-2003 followed up to the end of 2006

BACKGROUND

Previous studies have shown systematic differences between the Nordic Countries in population-based relative survival following a kidney or urinary bladder cancer diagnosis. Comparison of bladder cancer over time and between Nordic registries is complicated by variable coding practices with respect to the inclusion of in situ cases with invasive tumours.

MATERIAL AND METHODS

Five-year relative survival of patients with urinary cancer diagnosed in the Nordic countries 1964-2003 and followed up for death through 2006 was studied and contrasted with developments in incidence and mortality.

RESULTS

The survival following bladder cancer was higher than for kidney cancer and highest for men. Survival increased over the years in all countries, more for kidney cancer than bladder cancer. For Danish kidney cancer patients, the rate of increase over all the years has been lower than in the other countries, especially among women, resulting in a survival in Denmark some 10-20% points lower than elsewhere in 1999-2003. Danish bladder cancer patient survival was in the last period 4% points lower among men and 10% points lower among women than in the other Nordic countries. The differences were mainly found in the first year following diagnosis, where a higher excess mortality in Denmark was observed. Survival decreased with higher age at diagnosis.

CONCLUSION

The increasing 5-year relative survival in all the Nordic countries for both kidney and bladder cancer are promising, but for kidney cancer a higher percentage detected coincidentally during an imaging investigation for other diseases could play a role. Denmark had the lowest survival, despite their known practice of including benign conditions with invasive bladder cancers. The lower Danish survival after kidney and bladder cancer in the first year after diagnosis could be due to later diagnosis on average, a higher co-morbidity from smoking-related diseases, and perhaps, less adequate cancer treatment and management in Denmark.

Evidence of carcinogenicity in humans of water-soluble nickel salts

BACKGROUND

Increased risks of nasal cancer and lung cancer in nickel refiners have been investigated scientifically and discussed since they were detected in the 1930s. Nickel compounds are considered to be the main cause of the cancer excess. Parts of the nickel producing industry and their consultants oppose the classification of water-soluble nickel salts as human carcinogens, and argue that the risk in exposed workers should be ascribed to other occupational exposures and smoking.

DISCUSSION

Respiratory cancer risks in Welsh, Finnish, and Norwegian nickel refiners add to the evidence of carcinogenicity of water-soluble nickel. In Norwegian refiners, the first epidemiological study in 1973 identified high risks of lung cancer and nasal cancer among long-term electrolysis workers. Risk analyses based on exposure estimates developed in the 1980s supported the view that water-soluble nickel compounds were central in the development of cancer. Recently, new exposure estimates were worked out for the same cohort based on personal monitoring of total nickel and chemical determination of four forms of nickel. Additional data have been collected on life-time smoking habits, and on exposure to arsenic, asbestos, sulphuric acid mists, cobalt, and occupational lung carcinogens outside the refinery. After adjustment for these potential confounding exposures in case-control analyses, the risk pattern added to the evidence of an important role of water-soluble nickel compounds as causes of lung cancer. These Norwegian cancer studies rely on national Cancer Registry data, considered close to complete from 1953 onwards; and on National Population Register data continuously updated with mortality and emigration. Canadian mortality studies--perceived to offer the strongest support to the industry position not to recognise carcinogenicity of water-soluble nickel--appear to suffer from limitations in follow-up time, loss to follow-up, absence of risk analysis with individual exposure estimates, no confounder control, and a likely underestimation of cancer mortality.

CONCLUSIONS

Rejection to recognise water-soluble nickel as a human carcinogen seems to contradict material epidemiological evidence that demonstrates a strong association between water-soluble nickel compounds and risks of lung cancer and nasal cancer. Independent international scientific bodies have classified nickel compounds as carcinogenic to humans, inclusive of water-soluble nickel.

Parental occupation and risk of small-for-gestational-age births: a nationwide epidemiological study in Sweden

BACKGROUND

Although evidence suggests that some occupations may be a risk factor for small-for-gestational age (SGA) birth, associations between a wide range of maternal and paternal occupations and risk of SGA births remain unclear. Our objective was to analyze the risk of SGA births by parental occupation, including the entire Swedish population of mothers (> or =20 years) and fathers.

METHODS

We linked nationwide data (1990-2004) on singletons born to employed mothers to nationwide data on maternal and paternal occupation and other individual-level variables. Information on parental occupations was obtained from the 1990 census. Approximately 95% of SGA births (calculated using normative data) were defined on the basis of ultrasound. Odds ratios of SGA birth were calculated with 95% confidence intervals. Women and men were analyzed separately.

RESULTS

There were 816,310 first singleton live births during the study period, of which 29,603 were SGA events. Families with low incomes had an increased risk of SGA births. After accounting for maternal age at the infant's birth, period of birth, family income, region of residence, marital status and smoking habits, several maternal occupational groups (including 'mechanics and iron and metalware workers' and 'packers, loaders and warehouse workers') had a significantly higher risk of SGA birth than the reference group (all women in the study population). Among paternal occupational groups, only waiters had an increased risk of SGA birth.

CONCLUSIONS

This large-scale follow-up study shows that maternal occupation affects risk of SGA birth, whereas paternal occupation does not seem to have an impact on SGA birth. Further studies are required to examine the specific agents in those maternal occupations that are associated with an increased risk of SGA birth.

Lung cancer risk in painters: a meta-analysis

OBJECTIVE

We conducted a meta-analysis to quantitatively compare the association between occupation as a painter and the incidence or mortality from lung cancer.

DATA SOURCES

PubMed and the reference lists of pertinent publications were searched and reviewed. For the meta-analysis, we used data from 47 independent cohort, record linkage, and case control studies (from a total of 74 reports), including > 11,000 incident cases or deaths from lung cancer among painters.

DATA EXTRACTION

Three authors independently abstracted data and assessed study quality.

DATA SYNTHESIS

The summary relative risk (meta-RR, random effects) for lung cancer in painters was 1.35 [95% confidence interval (CI), 1.291.41; 47 studies] and 1.35 (95% CI, 1.211.51; 27 studies) after controlling for smoking. The relative risk was higher in never-smokers (meta-RR = 2.00; 95% CI, 1.093.67; 3 studies) and persisted when restricted to studies that adjusted for other occupational exposures (meta-RR = 1.57; 95% CI, 1.212.04; 5 studies). The results remained robust when stratified by study design, sex, and study location and are therefore unlikely due to chance or bias. Furthermore, exposure response analyses suggested that the risk increased with duration of employment.

CONCLUSION

These results support the conclusion that occupational exposures in painters are causally associated with the risk of lung cancer.

Socioeconomic differences in incidence of cervical cancer in Finland by cell type

INTRODUCTION

We studied variation in incidence of cervix cancer during 1971-1995 among Finnish women born in 1906 to 1945 by social class and cell type.

MATERIAL AND METHODS

The Finnish Cancer Registry data were linked to the 1970 Population Census, which included social class data. There were 0.8 million individuals in the cohort under follow-up, with 5,102 squamous cell cancers and 573 cases of cervical adenocarcinoma diagnosed after the census date.

RESULTS

Incidence of squamous cell cancer was more than two-fold in the lowest social class (standardized incidence ratio (SIR) 1.29, 95% CI 1.21-1.36) as compared with the highest one (SIR 0.59, 0.51-0.66), while there was no association between social class and risk on adenocarcinoma (SIR 1.07, 0.87-1.28 and 1.08, 0.79-1.45, respectively).

DISCUSSION

Oncogenic HPV is regarded as the necessary cause of all types of cervix cancer. Sexually transmitted diseases and social status are correlated. Lack of association between adenocarcinoma and social class makes the HPV-etiology of this cell type less credible than that of squamous cell cancer.

Recruitment of breast cancer survivors into a 12-month supervised exercise intervention is feasible

BACKGROUND

The BREX study is one of the largest randomised prospective exercise interventions of breast cancer survivors which aims at investigate whether regular exercise could reduce the long-term side effects of the adjuvant treatments and improve quality of life.

MATERIAL AND METHODS

The study was limited to consider patients aged 35-68 years, who had recently completed adjuvant chemotherapy or started endocrine therapy. In this paper, we describe the recruitment process of the 413 randomised patients from the Helsinki University Hospital between September 2005 and September 2007.

RESULTS

768 potentially eligible patients out of the 1321 screened (via medical records) were contacted by phone. After the phone call 240 patients were excluded due to health problems that contraindicated exercise training. The most common health problems were musculoskeletal disorders. A total of 528 patients were considered as eligible for the intervention. Ultimately 413 of them agreed to participate resulting in a 53.8% recruitment rate of the potentially eligible patients. The most important reasons for declining were social, not health related. Eligible patients who did not want to participate did not differ significantly from those who participated according to age, health status, breast cancer treatment and tumour type.

DISCUSSION

The high recruitment rate demonstrates breast cancer patient's willingness to participate even in long-lasting supervised exercise programs shortly after adjuvant treatments. After taking into account the selection of the population by age and musculoskeletal health, the results of the present intervention can be generalized to represent urban breast cancer patient population in Finland.