Statin use and outcomes of oncological treatment for castration-resistant prostate cancer.

To compare the effect of statin use in relation to castration-resistant prostate cancer (CRPC) treatment, we assessed the risk of ADT-treated PCa-patients to initiate CRPC treatment by statin use and the outcomes of CRPC treatment by statin use. Our study cohort consisted of 1169 men who participated in the Finnish Randomized Study of Screening for Prostate Cancer (FinRSPC) and initiated androgen deprivation therapy (ADT) during the follow-up (1996-2017). Statin use was associated with slightly decreased risk of initiating CRPC treatment (HR 0.68; 95% CI 0.47-0.97) with a 5.7 years' median follow-up until CRPC for non-users and 7.5 years for statin users. The risk of discontinuation of first or second line CRPC treatment due to inefficacy was not modified by statin use and the results remained similar in subgroup analysis assessing separately patients treated with taxans or androgen receptor signaling inhibitors. We observed an inverse association between statin use and the risk of initiation of the CRPC treatment. No beneficial risk modification by statin use during CRPC treatment was observed. These results suggest that statins might be beneficial during hormone-sensitive phase but not in the later phases of prostate cancer treatment.

Outcomes of prostate cancer screening among men using antidiabetic medication.

Diabetic men have decreased risk for prostate cancer (PCa) overall and lower PSA compared to non-diabetics. This may affect the outcomes of PSA-based screening. We investigated the effect of PSA-based screening at 4-year intervals on PCa incidence and mortality separately among users and non-users of antidiabetic medication with the hypothesis that screening would detect less low-grade cancer and more high-grade cancer in diabetic men. A cohort of 80,458 men from the Finnish Randomized Study of Screening for Prostate Cancer (FinRSPC) were linked to national prescription database to obtain information on antidiabetic medication purchases. PCa risk and mortality were compared between the FinRSPC screening arm (SA) and the control arm (CA) separately among users and non-users of antidiabetic medication. Among antidiabetic medication users median PSA was lower than in non-users (0.93 and 1.09 ng/ml, respectively, P for difference = 0.001). Screening increased overall PCa incidence compared to CA after the first screen both among medication users and non-users (HR 1.31, 95% CI 1.08-1.60 and HR 1.55, 95% CI 1.44-1.66, respectively). On the second and third screen the difference between SA and CA attenuated only among medication users. Detection of Gleason 6 tumors was lower among medication users, whereas no difference was observed in detection of Gleason 8-10 cancers. Concordantly, screening affected PCa mortality similarly regardless of antidiabetic medication use (HR 0.38, 95% CI 0.14-1.07 and HR 0.19, 95% CI 0.11-0.33 among users and non-users after three screens, respectively. P for difference = 0.18). Median PSA is lower in men using antidiabetic drugs than among non-users. Systematic PSA screening detects less low-risk tumors among medication users, whereas detection of high-risk tumors and mortality effects are similar regardless of medication use. This suggests that antidiabetic medication users may form a suitable target group for PCa screening, with less screening-related overdiagnosis of indolent tumors.

Prostate cancer prognosis after initiation of androgen deprivation therapy among statin users. A population-based cohort study.

PURPOSE: Statins' cholesterol-lowering efficacy is well-known. Recent epidemiological studies have found that inhibition of cholesterol synthesis may have beneficial effects on prostate cancer (PCa) patients, especially patients treated with androgen deprivation therapy (ADT). We evaluated statins' effect on prostate cancer prognosis among patients treated with ADT. MATERIALS AND METHODS: Our study population consisted of 8253 PCa patients detected among the study population of the Finnish randomized study of screening for prostate cancer. These were limited to 4428 men who initiated ADT during the follow-up. Cox proportional regression model adjusted for tumor clinical characteristics and comorbidities was used to estimate hazard ratios for risk of PSA relapse after ADT initiation and prostate cancer death. RESULTS: During the median follow-up of 6.3 years after the ADT initiation, there were 834 PCa deaths and 1565 PSA relapses in a study cohort. Statin use after ADT was associated with a decreased risk of PSA relapse (HR 0.73, 95% CI 0.65-0.82) and prostate cancer death (HR 0.82; 95% CI 0.69-0.96). In contrast, statin use defined with a one-year lag (HR 0.89, 95% CI 0.76-1.04), statin use before ADT initiation (HR 1.12, 95% CI 0.96-1.31), and use in the first year on ADT (HR 1.02, 95% CI 0.85-1.24) were not associated with prostate cancer death, without dose dependency. CONCLUSION: Statin use after initiation of ADT, but not before, was associated with improved prostate cancer prognosis.

Anticoagulants and cancer mortality in the Finnish randomized study of screening for prostate cancer.

PURPOSE: Anticoagulants may reduce mortality of cancer patients, though the evidence remains controversial. We studied the association between different anticoagulants and cancer death. METHODS: All anticoagulant use during 1995-2015 was analyzed among 75,336 men in the Finnish Randomized Study of Screening for Prostate Cancer. Men with prevalent cancer were excluded. Multivariable Cox regression was performed to compare risk of death from any cancer and disease-specific death from 9 specific cancer types between (1) anticoagulant users overall and (2) warfarin users compared to anticoagulant non-users and (3) warfarin or (4) low-molecular-weight heparins (LMWH) compared to users of other anticoagulants. Medication use was analyzed as time-dependent variable to minimize immortal time bias. 1-, 2- and 3-year lag-time analyses were performed. RESULTS: During a median follow-up of 17.2 years, a total of 27,233 men died of whom 8033 with cancer as the primary cause of death. In total, 32,628 men (43%) used anticoagulants. Any anticoagulant use was associated with an increased risk of cancer death (HR = 2.50, 95% CI 2.37-2.64) compared to non-users. Risk was similar independent of the amount, duration, or intensity of use. The risk increase was observed both among warfarin and LMWH users, although not as strong in warfarin users. Additionally, cancer-specific risks of death were similar to overall cancer mortality in all anticoagulant categories. CONCLUSION: Our study does not support reduced cancer mortality among anticoagulant users. Future studies on drug use and cancer mortality should be adjusted for anticoagulants as they are associated with significantly higher risk of cancer death.

Multidisciplinary European Low Dose Initiative (MELODI): strategic research agenda for low dose radiation risk research.

MELODI (Multidisciplinary European Low Dose Initiative) is a European radiation protection research platform with focus on research on health risks after exposure to low-dose ionising radiation. It was founded in 2010 and currently includes 44 members from 18 countries. A major activity of MELODI is the continuous development of a long-term European Strategic Research Agenda (SRA) on low-dose risk for radiation protection. The SRA is intended to identify priorities for national and European radiation protection research programs as a basis for the preparation of competitive calls at the European level. Among those key priorities is the improvement of health risk estimates for exposures close to the dose limits for workers and to reference levels for the population in emergency situations. Another activity of MELODI is to ensure the availability of European key infrastructures for research activities, and the long-term maintenance of competences in radiation research via an integrated European approach for training and education. The MELODI SRA identifies three key research topics in low dose or low dose-rate radiation risk research: (1) dose and dose rate dependence of cancer risk, (2) radiation-induced non-cancer effects and (3) individual radiation sensitivity. The research required to improve the evidence base for each of the three key topics relates to three research lines: (1) research to improve understanding of the mechanisms contributing to radiogenic diseases, (2) epidemiological research to improve health risk evaluation of radiation exposure and (3) research to address the effects and risks associated with internal exposures, differing radiation qualities and inhomogeneous exposures. The full SRA and associated documents can be downloaded from the MELODI website ( http://www.melodi-online.eu/sra.html ).

Prostate cancer risk among users of digoxin and other antiarrhythmic drugs in the Finnish Prostate Cancer Screening Trial.

PURPOSE: Long-term usage of the antiarrhythmic drug digoxin has been connected to lowered risk of prostate cancer. A recent study has suggested that beta-blockers might also have similar risk-decreasing effects. We evaluated the association between use of digoxin, beta-blocker sotalol, and other antiarrhythmic drugs and prostate cancer risk in a retrospective cohort study. METHODS: Our study population consisted of men in the Finnish Prostate Cancer Screening Trial during 1996-2012 (n = 78,615). During median follow-up of 12 years, 6,639 prostate cancer cases were diagnosed. The national prescription database was the source of the information of antiarrhythmic drug purchases. Data were analyzed using Cox regression method with medication use as a time-dependent variable. RESULTS: No association was found for overall prostate cancer risk with antiarrhythmic drug use (HR 1.05 95% CI 0.94-1.18). Neither sotalol (HR 0.97 95% CI 0.76-1.24) nor digoxin (HR 1.01 95% CI 0.87-1.16) users had a decreased risk of prostate cancer. Similar results were obtained for high-grade (Gleason 7-10) and metastatic prostate cancer. Nevertheless, the risk estimates for Gleason 7-10 prostate cancer tended to decrease by duration of digoxin use (p for trend = 0.052), suggesting that the drug may reduce the risk in long-term usage (HR 0.71, 95% CI 0.49-1.03). In analysis stratified by screening trial arm, the protective association against Gleason 7-10 disease was observed only in the screening arm (HR 0.31, 95% CI 0.12-0.84 for men who had used digoxin for 5 years or longer). CONCLUSION: Digoxin or other antiarrhythmic drugs are not associated with any clear decrease in prostate cancer risk. However, digoxin might have a benefit in long-term use by reducing risk of high-grade disease. Further research will be needed to evaluate possible effects on prostate cancer survival.

Cost-effectiveness of prostate cancer screening: a simulation study based on ERSPC data.

BACKGROUND: The results of the European Randomized Study of Screening for Prostate Cancer (ERSPC) trial showed a statistically significant 29% prostate cancer mortality reduction for the men screened in the intervention arm and a 23% negative impact on the life-years gained because of quality of life. However, alternative prostate-specific antigen (PSA) screening strategies for the population may exist, optimizing the effects on mortality reduction, quality of life, overdiagnosis, and costs. METHODS: Based on data of the ERSPC trial, we predicted the numbers of prostate cancers diagnosed, prostate cancer deaths averted, life-years and quality-adjusted life-years (QALY) gained, and cost-effectiveness of 68 screening strategies starting at age 55 years, with a PSA threshold of 3, using microsimulation modeling. The screening strategies varied by age to stop screening and screening interval (one to 14 years or once in a lifetime screens), and therefore number of tests. RESULTS: Screening at short intervals of three years or less was more cost-effective than using longer intervals. Screening at ages 55 to 59 years with two-year intervals had an incremental cost-effectiveness ratio of $73000 per QALY gained and was considered optimal. With this strategy, lifetime prostate cancer mortality reduction was predicted as 13%, and 33% of the screen-detected cancers were overdiagnosed. When better quality of life for the post-treatment period could be achieved, an older age of 65 to 72 years for ending screening was obtained. CONCLUSION: Prostate cancer screening can be cost-effective when it is limited to two or three screens between ages 55 to 59 years. Screening above age 63 years is less cost-effective because of loss of QALYs because of overdiagnosis.

A framework for estimating radiation-related cancer risks in Japan from the 2011 Fukushima nuclear accident.

We present here a methodology for health risk assessment adopted by the World Health Organization that provides a framework for estimating risks from the Fukushima nuclear accident after the March 11, 2011 Japanese major earthquake and tsunami. Substantial attention has been given to the possible health risks associated with human exposure to radiation from damaged reactors at the Fukushima Daiichi nuclear power station. Cumulative doses were estimated and applied for each post-accident year of life, based on a reference level of exposure during the first year after the earthquake. A lifetime cumulative dose of twice the first year dose was estimated for the primary radionuclide contaminants ((134)Cs and (137)Cs) and are based on Chernobyl data, relative abundances of cesium isotopes, and cleanup efforts. Risks for particularly radiosensitive cancer sites (leukemia, thyroid and breast cancer), as well as the combined risk for all solid cancers were considered. The male and female cumulative risks of cancer incidence attributed to radiation doses from the accident, for those exposed at various ages, were estimated in terms of the lifetime attributable risk (LAR). Calculations of LAR were based on recent Japanese population statistics for cancer incidence and current radiation risk models from the Life Span Study of Japanese A-bomb survivors. Cancer risks over an initial period of 15 years after first exposure were also considered. LAR results were also given as a percentage of the lifetime baseline risk (i.e., the cancer risk in the absence of radiation exposure from the accident). The LAR results were based on either a reference first year dose (10 mGy) or a reference lifetime dose (20 mGy) so that risk assessment may be applied for relocated and non-relocated members of the public, as well as for adult male emergency workers. The results show that the major contribution to LAR from the reference lifetime dose comes from the first year dose. For a dose of 10 mGy in the first year and continuing exposure, the lifetime radiation-related cancer risks based on lifetime dose (which are highest for children under 5 years of age at initial exposure), are small, and much smaller than the lifetime baseline cancer risks. For example, after initial exposure at age 1 year, the lifetime excess radiation risk and baseline risk of all solid cancers in females were estimated to be 0.7 · 10(-2) and 29.0 · 10(-2), respectively. The 15 year risks based on the lifetime reference dose are very small. However, for initial exposure in childhood, the 15 year risks based on the lifetime reference dose are up to 33 and 88% as large as the 15 year baseline risks for leukemia and thyroid cancer, respectively. The results may be scaled to particular dose estimates after consideration of caveats. One caveat is related to the lack of epidemiological evidence defining risks at low doses, because the predicted risks come from cancer risk models fitted to a wide dose range (0-4 Gy), which assume that the solid cancer and leukemia lifetime risks for doses less than about 0.5 Gy and 0.2 Gy, respectively, are proportional to organ/tissue doses: this is unlikely to seriously underestimate risks, but may overestimate risks. This WHO-HRA framework may be used to update the risk estimates, when new population health statistics data, dosimetry information and radiation risk models become available.

Prostate cancer risk and nonsteroidal antiinflammatory drug use in the Finnish prostate cancer screening trial.

BACKGROUND: The association between nonsteroidal antiinflammatory drugs (NSAIDs) and prostate cancer risk remains controversial. We examined the risk among NSAID users in 78 615 men in the Finnish Prostate Cancer Screening Trial. METHODS: We obtained information on NSAID prescription usage from Finnish nationwide prescription database and on over-the-counter use by a questionnaire. Prostate cancer cases were identified from the Finnish Cancer Registry. RESULTS: Prostate cancer risk was elevated among current NSAID prescription users irrespective of screening (hazard ratio (HR)=1.45, confidence interval (95% CI)=1.33-1.59 and HR=1.71, 95% CI=1.58-1.86 in the screening and control arm, respectively), but not for previous use of NSAIDs. The risk increase was similar among coxib and acetaminophen current users, and stronger for metastatic prostate cancer (HR=2.41, 95% CI=1.59-3.67 and HR=3.44, 95% CI=2.60-4.55 in the screening and control arm, respectively). Previous use of NSAIDs, aspirin use and over-the-counter NSAID usage were not associated with prostate cancer. CONCLUSIONS: Differing association for current and previous use suggests that the risk increase is unlikely to be directly caused by the medication, but may be due to the conditions indicating NSAID prescription usage, such as symptoms of undiagnosed prostate cancer. To reduce inconsistency between the study outcomes, future epidemiological studies on NSAID use and prostate cancer risk should assess the indications for NSAID usage.

Childhood leukaemia risks: from unexplained findings near nuclear installations to recommendations for future research.

Recent findings related to childhood leukaemia incidence near nuclear installations have raised questions which can be answered neither by current knowledge on radiation risk nor by other established risk factors. In 2012, a workshop was organised on this topic with two objectives: (a) review of results and discussion of methodological limitations of studies near nuclear installations; (b) identification of directions for future research into the causes and pathogenesis of childhood leukaemia. The workshop gathered 42 participants from different disciplines, extending widely outside of the radiation protection field. Regarding the proximity of nuclear installations, the need for continuous surveillance of childhood leukaemia incidence was highlighted, including a better characterisation of the local population. The creation of collaborative working groups was recommended for consistency in methodologies and the possibility of combining data for future analyses. Regarding the causes of childhood leukaemia, major fields of research were discussed (environmental risk factors, genetics, infections, immunity, stem cells, experimental research). The need for multidisciplinary collaboration in developing research activities was underlined, including the prevalence of potential predisposition markers and investigating further the infectious aetiology hypothesis. Animal studies and genetic/epigenetic approaches appear of great interest. Routes for future research were pointed out.

Outcomes of medical and surgical treatment for lower urinary tract symptoms (benign prostatic obstruction)--a population-based cohort study.

OBJECTIVE: To compare outcome of lower urinary tract symptoms (LUTS) between men with medical and surgical treatment. MATERIALS AND METHODS: A questionnaire was mailed to men aged 55, 65 and 75 years living in Tampere region, Finland in 1999 and the survey was repeated in 2004. LUTS were evaluated using DAN-PSS-1 questionnaire. A total of 1679 men (68% of the eligible) responded to both questionnaires. Of them, 114 men reported LUTS at baseline and medical treatment in the repeat survey and 47 men with LUTS had received surgical treatment. Seventy-two men with prostate cancer were excluded. Men with no medical treatment or surgery for LUTS in either questionnaire were included to no-treatment group. RESULTS: The men after surgical treatment showed a reduction in all LUTS symptom groups. However, among the medically treated and untreated men, all the symptoms worsened during the follow up. The proportion of symptomatic men after surgery was lower than among the medically treated men. In men with medical treatment, the prevalence of all 12 LUTS increased. Dysuria and postmicturition dribble were the only symptoms that had slightly better results in medical than in surgical treatment group. CONCLUSIONS: In this population-based study, operative treatment seemed to relieve LUTS, whereas medical treatment only slowed down their progression. These findings suggest that men with surgical treatment experience a more favourable outcome in LUTS than those receiving medical treatment.

Industrial worker exposure to airborne particles during the packing of pigment and nanoscale titanium dioxide.

CONTEXT: Titanium dioxide (TiO2) factory workers' source specific exposure and dose to airborne particles was studied extensively for particles between 5 nm and 10 µm in size. OBJECTIVE: We defined TiO2 industry workers' quantitative inhalation exposure levels during the packing of pigment TiO2 (pTiO2) and nanoscale TiO2 (nTiO2) material from concentrations measured at work area. METHODS: Particle emissions from different work events were identified by linking work activity with the measured number size distributions and mass concentrations of particles. A lung deposit model was used to calculate regional inhalation dose rates in units of particles min⁻¹ and µg min⁻¹ without use of respirators. RESULTS: Workers' average exposure varied from 225 to 700 µg m⁻³ and from 1.15 × 104 to 20.1 × 104 cm⁻4. Over 90% of the particles were smaller than 100 nm. These were mainly soot and particles formed from process chemicals. Mass concentration originated primarily from the packing of pTiO2 and nTiO2 agglomerates. The nTiO2 exposure resulted in a calculated dose rate of 3.6 × 106 min⁻¹ and 32 µg min⁻¹ where 70% of the particles and 85% of the mass was deposited in head airways. CONCLUSIONS: The recommended TiO2 exposure limits in mass by NIOSH and in particle number by IFA were not exceeded. We recommend source-specific exposure assessment in order to evaluate the workers' risks. In nTiO2 packing, mass concentration best describes the workers' exposure to nTiO2 agglomerates. Minute dose rates enable the simulation of workers' risks in different exposure scenarios.

Incidence trends of vestibular schwannomas in Denmark, Finland, Norway and Sweden in 1987-2007.

BACKGROUND: The reported incidence rates of vestibular schwannomas (VS) vary substantially, but it is unclear as to what extent the variation reflects differences in risk or recording practices. Our aim was to describe the incidence rates of VS in Denmark, Finland, Norway and Sweden between 1987 and 2007. METHODS: Comprehensive data were available from all registries only for the period from 1987 to 2007. An analysis of a longer time period (1965-2007) was conducted with the Norwegian and Swedish data. RESULTS: The average age-standardised incidence rates during 1987-2007 varied from 6.1 per 1,000,000 person-years (95% confidence interval (CI), 5.4-6.7) among Finnish men to 11.6 (95% CI, 10.4-12.7) in Danish men, and from 6.4 per 1,000,000 person-years (95% CI, 5.7-7.0) among Swedish women to 11.6 (95% CI, 10.5-12.8) among Danish women. An overall annual increase of 3.0% (95% CI 2.1-3.9) was observed when all countries and both sexes were combined, with considerable differences between countries. However, the practices of both reporting and coding VS cases varied markedly between countries and over time, which poses a challenge for interpretation of the results. CONCLUSION: The overall incidence of VS increased in all the four Nordic countries combined between 1987 and 2007, with marked differences between countries. However, the incidence rates more or less stabilised in the late 1990s, showing relatively constant incidence rates and even some decline after 2000.

Prostate cancer incidence and mortality trends in 37 European countries: an overview.

Prostate cancer has emerged as the most frequent cancer amongst men in Europe, with incidence increasing rapidly over the past two decades. Incidence has been uniformly increasing in the 24 countries with comparable data available, although in a few countries with very high rates (Sweden, Finland and The Netherlands), incidence has begun to fall during the last 3-4 years. The highest prostate cancer mortality rates are in the Baltic region (Estonia, Latvia and Lithuania) and in Denmark, Norway and Sweden. Prostate cancer mortality has been decreasing in 13 of the 37 European countries considered - predominantly in higher-resource countries within each region - beginning in England and Wales (1992) and more recently in the Czech Republic (2004). There was considerable variability in the magnitude of the annual declines, varying from approximately 1% in Scotland (from 1994) to over 4% for the more recent declines in Hungary, France and the Czech Republic. There appears little relation between the extent of the increases in incidence (in the late 1990s) and the recent mortality declines. It remains unclear to what extent the increasing trends in incidence indicate true risk and how much is due to detection of latent disease. The decreasing mortality after 1990 may be attributable to improvements in treatment and to an effect of prostate specific antigen (PSA) testing. The increase in mortality observed in the Baltic region and in several Central and Eastern European countries appear to reflect a real increase in risk and requires further monitoring.

Exogenous sex hormone use and risk of meningioma: a population-based case-control study in Finland.

BACKGROUND: Previous studies on association of exogenous female sex hormones and risk for meningioma have yielded conflicting results. The aim of this study was to evaluate the potential relation between prior use of menopausal hormone therapy or oral contraception and risk of meningioma. METHODS: This population-based case-control study was conducted during years 2000-2002 in Finland. All women aged 20-69 years with meningioma diagnosis were identified from five university hospitals, and frequency-matched controls were randomly chosen from population register. A total of 264 cases and 505 controls were interviewed on their use of menopausal hormone therapy, oral and other contraception, fertility treatment, treatment for gynecological problems, age at menarche, and number of children. We also analyzed separately tumors expressing progesterone or estrogen receptors. Of the successfully stained tumor specimens, 86.3% were positive for progesterone receptor and 50% for estrogen receptor. RESULTS: Postmenopausal hormonal treatment, use of contraceptives, or fertility treatment did not influence the risk of meningioma. In further analysis by hormone receptor status, there was some indication for an increased risk of progesterone receptor-positive meningiomas associated with oral contraceptive use (OR 1.39, 95% confidence interval 0.92-2.10) and other hormonal contraception (OR 1.50, 95% CI 0.95-2.36). CONCLUSIONS: Overall, we found little indication that reproductive factors or use of exogenous sex hormones affect meningioma risk.

False-positive screening results in the Finnish prostate cancer screening trial.

BACKGROUND: There is evidence that prostate cancer (PC) screening with prostate-specific antigen (PSA) serum test decreases PC mortality, but screening has adverse effects, such as a high false-positive (FP) rate. We investigated the proportion of FPs in a population-based randomised screening trial in Finland. METHODS: Finland is the largest centre in the European Randomized Study of Screening for Prostate Cancer. We have completed three screening rounds with a 4-year screening interval (mean follow-up time 9.2 years) using a PSA cutoff level of 4.0 ng ml(-1); in addition, men with PSA 3.0-3.9 and a positive auxiliary test were referred. An FP result was defined as a positive screening result without cancer in biopsy within 1 year from the screening test. RESULTS: The proportion of FP screening results varied from 3.3 to 12.1% per round. Of the screened men, 12.5% had at least one FP during three rounds. The risk of next-round PC following an FP result was 12.3-19.7 vs 1.4-3.7% following a screen-negative result (depending on the screening round), risk ratio 3.6-9.9. More than half of the men with one FP result had another one at a subsequent screen. Men with an FP result were 1.5 to 2.0 times more likely to not participate in subsequent rounds compared with men with a normal screening result (21.6-29.6 vs 14.0-16.7%). CONCLUSION: An FP result is a common adverse effect of PC screening and affects at least every eighth man screened repeatedly, even when using a relatively high cutoff level. False-positive men constitute a special group that receives unnecessary interventions but may harbour missed cancers. New strategies are needed for risk stratification in PC screening to minimise the proportion of FP men.

Development of a highly controlled gas-phase nanoparticle generator for inhalation exposure studies.

We have developed a gas-phase nanoparticle generator that produces stable and well-defined size distributions for TiO(2). The online analyses of the gas-phase compounds and total number concentration of the generated particles as well as the off-line analysis of the filter samples confirmed the stability of the production. The major advantage of this reactor is that the test substance is directly in the aerosol phase, and thus no preprocessing is needed. This eliminates the physicochemical changes between bulk and administrated material during storing or processing. This system is easy to adjust to different experimental setups and precursors. As a result, well-characterized nanomaterials for inhalation exposure studies can be produced. At mass concentration of 30 mg/Nm(3), the count mean diameter was 126 nm (geometric SD 1.6), mass mean diameter was 161 nm (2.0), mass median aerodynamic diameter was 125 nm, and the concentrations of harmful gas-phase by-products remained low. The produced powder consisted of crystals of anatase (77 vol%) and brookite (23 vol%), and its specific surface area was 69 m(2)/g.

Prostate cancer incidence among finasteride and alpha-blocker users in the Finnish Prostate Cancer Screening Trial.

BACKGROUND: The Prostate Cancer Prevention Trial has shown a protective effect of finasteride on prostate cancer in low-risk men. It is uncertain whether similar results can be expected when finasteride is used to treat benign prostatic hyperplasia. METHODS: We performed an observational cohort study within the Finnish Prostate Cancer Screening Trial. Using a comprehensive prescription database on medication reimbursements during 1995-2004 of men using finasteride or alpha-blockers for benign prostatic hyperplasia, we evaluated prostate cancer incidence among 23 320 men screened during 1996-2004. RESULTS: Compared to medication non-users, overall prostate cancer incidence was not significantly affected in finasteride users (hazard ratio 0.87; 95% CI 0.63-1.19). Incidence of Gleason 2-6 tumours, however, was decreased among finasteride users (HR 0.59; 95% CI 0.38-0.91), whereas incidence of Gleason 7-10 tumours was unchanged (HR 1.33; 95% CI 0.77-2.30). The protective effect concerned mainly screen-detected tumours. Overall prostate cancer risk was not significantly reduced among alpha-blocker users relative to non-users, but decreased incidence of high-grade tumours was observed (0.55; 95% CI 0.31-0.96). CONCLUSIONS: The detection of low-grade, early-stage tumours is decreased among men who use finasteride for symptomatic BPH. The protective effect of finasteride can also be expected in men with benign prostatic hyperplasia.

Meningioma and mobile phone use--a collaborative case-control study in five North European countries.

BACKGROUND: Use of mobile telephones has been suggested as a possible risk factor for intracranial tumours. To evaluate the effect of mobile phones on risk of meningioma, we carried out an international, collaborative case-control study of 1209 meningioma cases and 3299 population-based controls. METHODS: Population-based cases were identified, mostly from hospitals, and controls from national population registers and general practitioners' patient lists. Detailed history of mobile phone use was obtained by personal interview. Regular mobile phone use (at least once a week for at least 6 months), duration of use, cumulative number and hours of use, and several other indicators of mobile phone use were assessed in relation to meningioma risk using conditional logistic regression with strata defined by age, sex, country and region. RESULTS: Risk of meningioma among regular users of mobile phones was apparently lower than among never or non-regular users (odds ratio, OR = 0.76, 95% confidence interval, CI 0.65, 0.89). The risk was not increased in relation to years since first use, lifetime years of use, cumulative hours of use or cumulative number of calls. The findings were similar regardless of telephone network type (analogue/digital), age or sex. CONCLUSIONS: Our results do not provide support for an association between mobile phone use and risk of meningioma.

Is the incidence of meningiomas underestimated? A regional survey.

We assessed the undercount of meningiomas in a population-based cancer registry. A comprehensive material was formed by compiling hospital sources with the Finnish Cancer Registry database. The completeness of each source ranged 62-69%. The corrected age-standardised meningioma incidence was 2.9/100,000 for men and 13.0/100,000 for women, a third higher than the cancer registry figures.