Objective
To review and quantify the association between endogenous and exogenous testosterone and prostate‐specific antigen (PSA) and prostate cancer.
Methods
Literature searches were performed ...according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. Prospective cohort studies that reported data on the associations between endogenous testosterone and prostate cancer, and placebo‐controlled randomized trials of testosterone replacement therapy (TRT) that reported data on PSA and/or prostate cancer cases were retained. Meta‐analyses were performed using random‐effects models, with tests for publication bias and heterogeneity.
Results
Twenty estimates were included in a meta‐analysis, which produced a summary relative risk (SRR) of prostate cancer for an increase of 5 nmol/L of testosterone of 0.99 (95% confidence interval CI 0.96, 1.02) without heterogeneity (I² = 0%). Based on 26 trials, the overall difference in PSA levels after onset of use of TRT was 0.10 ng/mL (−0.28, 0.48). Results were similar when conducting heterogeneity analyses by mode of administration, region, age at baseline, baseline testosterone, trial duration, type of patients and type of TRT. The SRR of prostate cancer as an adverse effect from 11 TRT trials was 0.87 (95% CI 0.30; 2.50). Results were consistent across studies.
Conclusions
Prostate cancer appears to be unrelated to endogenous testosterone levels. TRT for symptomatic hypogonadism does not appear to increase PSA levels nor the risk of prostate cancer development. The current data are reassuring, although some caution is essential until multiple studies with longer follow‐up are available.
Anatomical UV Exposure in French Outdoor Workers Vernez, David; Koechlin, Alice; Milon, Antoine ...
Journal of occupational and environmental medicine,
2015-November, Letnik:
57, Številka:
11
Journal Article
Recenzirano
Odprti dostop
BACKGROUND:Solar ultraviolet has been recognized as the main causative factor for skin cancer and is currently classified as a carcinogenic agent by International Agency for Research on Cancer.
...METHOD:Results from a previous phone survey conducted in 2012 in France were used to assess exposure conditions to sun among outdoor workers. Satellite data were used in combination with an exposure model to assess anatomical exposure.
RESULT:The yearly median exposure of the outdoor worker population is 77 kJ/m to 116 kJ/m. Road workers, building workers, and gardeners are the more exposed. About 70% of the yearly dose estimate is due to the cumulative summer and spring exposures.
CONCLUSIONS:This study highlights the role of individual factors in anatomical exposure and ranks the most exposed body parts and outdoor occupations. Prevention messages should put emphasis on spring exposure, which is an important contributor to the yearly dose.
Occupational exposures in the rubber manufacturing industry showed an increased risk of cancer and have been classified as a group 1 carcinogen, largely from studies on workers employed before 1950s. ...Cancer sites considered as causally associated are bladder, lung and stomach, and leukaemia. Recent studies did not report an increased risk of cancer.
A meta-analysis was conducted on observational studies published until April 2016 on occupational exposures in the rubber manufacturing industry and risk of cancer. Case-control and cohort studies were included. Random effect models were used. Heterogeneity and publication bias were evaluated. Stratified analyses were conducted on study characteristics.
The literature search identified 46 cohorts and 59 case-control studies. An increased risk was found for bladder cancer standardised incidence ratio (SRR) = 1.36; 95% confidence interval (CI) 1.18, 1.57, leukaemia (SRR = 1.29; 95% CI 1.11, 1.52), lymphatic and haematopoietic system (SRR = 1.16; 95% CI 1.02, 1.31) and larynx cancer (SRR = 1.46; 95% CI 1.10, 1.94). For lung cancer, a borderline statistically significant increased risk was identified (SRR = 1.08; 95% CI 0.99, 1.17). No association was found for stomach cancer (SRR = 1.06; 95% CI 0.95, 1.17). In stratified analyses, risks of cancer were not increased for workers employed after 1960 for bladder cancer (SRR = 1.06; 95% CI 0.66, 1.71), lung cancer (SRR = 0.94; 95% CI 0.68, 1.29) or leukaemia (SRR = 0.92; 95% CI 0.62, 1.36).
Risk of bladder cancer, lung cancer, leukaemia and larynx cancer were increased among workers in rubber industry. Evidence of elevated risks was no longer seen for bladder cancer, lung cancer or leukemia among workers first employed after 1960.
AbstractObjectiveTo analyse stage specific incidence of breast cancer in the Netherlands where women have been invited to biennial mammography screening since 1989 (ages 50-69) and 1997 (ages 70-75), ...and to assess changes in breast cancer mortality and quantified overdiagnosis.DesignPopulation based study.SettingMammography screening programme, the Netherlands.ParticipantsDutch women of all ages, 1989 to 2012.Main outcome measuresStage specific age adjusted incidence of breast cancer from 1989 to 2012. The extra numbers of in situ and stage 1 breast tumours associated with screening were estimated by comparing rates in women aged 50-74 with those in age groups not invited to screening. Overdiagnosis was estimated after subtraction of the lead time cancers. Breast cancer mortality reductions during 2010-12 and overdiagnosis during 2009-11 were computed without (scenario 1) and with (scenario 2) a cohort effect on mortality secular trends.ResultsThe incidence of stage 2-4 breast cancers in women aged 50 or more was 168 per 100 000 in 1989 and 166 per 100 000 in 2012. Screening would be associated with a 5% mortality reduction in scenario 1 and with no influence on mortality in scenario 2. In both scenarios, improved treatments would be associated with 28% reductions in mortality. Overdiagnosis has steadily increased over time with the extension of screening to women aged 70-75 and with the introduction of digital mammography. After deduction of clinical lead time cancers, 32% of cancers found in women invited to screening in 2010-12 and 52% of screen detected cancers would be overdiagnosed.ConclusionsThe Dutch mammography screening programme seems to have little impact on the burden of advanced breast cancers, which suggests a marginal effect on breast cancer mortality. About half of screen detected breast cancers would represent overdiagnosis.
Abstract Background Lower risk of breast cancer has been reported among physically active women, but the risk in women using hormone replacement therapy (HRT) appears to be higher. We quantified the ...association between physical activity and breast cancer, and we examined the influence that HRT use and other risk factors had on this association. Methods After a systematic literature search, prospective studies were meta-analysed using random-effect models applied on highest versus lowest level of physical activity. Dose–response analyses were conducted with studies reporting physical activity either in hours per week or in hours of metabolic equivalent per week (MET-h/week). Results The literature search identified 38 independent prospective studies published between 1987 and 2014 that included 116,304 breast cancer cases. Compared to the lowest level of physical activity, the highest level was associated with a summary relative risk (SRR) of 0.88 (95% confidence interval CI 0.85, 0.90) for all breast cancer, 0.89 (95% CI 0.83, 0.95) for ER+/PR+ breast cancer and 0.80 (95% CI 0.69, 0.92) for ER−/PR− breast cancer. Risk reductions were not influenced by the type of physical activity (occupational or non-occupational), adiposity, and menopausal status. Risk reductions increased with increasing amounts of physical activity without threshold effect. In six studies, the SRR was 0.78 (95% CI 0.70, 0.87) in women who never used HRT and 0.97 (95% CI 0.88, 1.07) in women who ever used HRT, without heterogeneity in results. Findings indicate that a physically inactive women engaging in at least 150 min per week of vigorous physical activity would reduce their lifetime risk of breast cancer by 9%, a reduction that might be two times greater in women who never used HRT. Conclusion Increasing physical activity is associated with meaningful reductions in the risk of breast cancer, but in women who ever used HRT, the preventative effect of physical activity seems to be cancelled out.
To describe the incidence and mortality rates from colon and rectal cancer in Midwestern Brazil.
Data for the incidence rates were obtained from the Population-Based Cancer Registry (PBCR) according ...to the available period. Mortality data were obtained from the Mortality Information System (SIM) for the period between 1996 and 2008. Incidence and mortality rates were calculated by gender and age groups. Mortality trends were analyzed by the Joinpoint software. The age-period-cohort effects were calculated by the R software.
The incidence rates for colon cancer vary from 4.49 to 23.19/100,000, while mortality rates vary from 2.85 to 14.54/100,000. For rectal cancer, the incidence rates range from 1.25 to 11.18/100,000 and mortality rates range between 0.30 and 7.90/100,000. Colon cancer mortality trends showed an increase among males in Cuiabá, Campo Grande, and Goiania. For those aged under 50 years, the increased rate was 13.2% in Campo Grande. For those aged over 50 years, there was a significant increase in the mortality in all capitals. In Goiânia, rectal cancer mortality in males increased 7.3%. For females below 50 years of age in the city of Brasilia, there was an increase of 8.7%, while females over 50 years of age in Cuiaba showed an increase of 10%.
There is limited data available on the incidence of colon and rectal cancer for the Midwest region of Brazil. Colon cancer mortality has generally increased for both genders, but similar data were not verified for rectal cancer. The findings presented herein demonstrate the necessity for organized screening programs for colon and rectal cancer in Midwestern Brazil.
The CPRD has been collecting medical data among UK patients since 1987. Many studies on the risk of cancer associated with prescription of antidiabetic drugs have used the CRPD database. The ...objective was to compare methods and results of studies on the same exposure and outcome combination based on the CPRD.A systematic Pubmed search of articles on diabetes and cancer based on the CPRD was performed. Articles were grouped into common exposure and outcome combinations. Methods and results were compared, especially in case of diverging results between studies, with a focus on study design and statistical methods. Forty-six studies were identified. Five of them studied colorectal cancer (CRC) occurrence in diabetic patients prescribed with metformin. All studies consistently found no significant increased or decreased CRC risk associated with metformin prescription. Five studies examined the risk of bladder cancer in relation to pioglitazone prescription. Two studies found a significantly increased risk of bladder cancer, one based on the analysis of the full dataset and one based on a nested case-control design using conventional matching procedures. The three other studies found no association, all of which used propensity score matched cohort design. Four studies investigated the risk of breast cancer among insulin glargine users. The three studies that included diabetic subjects who were prescribed glargine or another insulin therapy for the first time (i.e., the new user design) found no association. The study that included past and new users of glargine and of another insulin found a significantly increased risk. Despite the use of the same data source, studies on the same exposure and outcome may arrive at markedly different conclusions. Studies using propensity scores for matching subjects or including past users in cohorts may obtain results substantially different than studies using conventional statistical approaches.
Disclosure
A. Koechlin: None. P. Boyle: Other Relationship; Self; Sanofi. P. Autier: Other Relationship; Self; Sanofi.
Abstract Background Reasons underlying time changes in cutaneous melanoma mortality in light-skinned populations are not well understood. An analysis of long-term time trends in melanoma mortality ...was carried out after regrouping countries in homogeneous regions. Methods Using the World Health Organisation (WHO) mortality database, age–period–cohort models were fitted for seven regions where the majority of population is light-skinned. Cohort effects are denoted as changes in rates occurring at different times in steadily older age groups. Period effects are denoted as changes in rates occurring simultaneously in several age groups. Results Cohort effects better explained changes in melanoma mortality over time than period effects. Lifetime risk to die from melanoma increased in successive generations from 1875 until a peak year. Peak years were for subjects born in 1936–1940 in Oceania, 1937–1943 in North America, 1941–1942 in Northern Europe, 1945–1953 in the United Kingdom (UK) and Ireland, 1948 in Western Europe and 1957 in Central Europe. After peak years, lifetime risk of melanoma death gradually decreased in successive generations and risks of subjects born in 1990–1995 were back to risk levels observed for subjects born before 1900–1905. In Southern Europe, birth years with highest lifetime risk of melanoma death have not yet been attained. As time passes, melanoma deaths will steadily rarefy in younger age groups and concentrate in older age groups, for ultimately fade away after 2040–2050. Conclusion Independently from screening or treatment, over next decades, death from melanoma is likely to become an increasingly rare event. The temporary epidemic of fatal melanoma was most probably due to excessive UV-exposure of children that prevailed in 1900–1960, and mortality decreases would be due to progressive reductions in UV-exposure of children over the last decades.
Breast cancer is the commonest form of cancer in women worldwide. It has been suggested that chronic hyperinsulinemia associated with insulin resistance plays a role in breast cancer etiology. To ...test the hyperinsulinemia hypothesis, a dietary pattern associated with a high glycemic index and glycemic load, both proxies for chronic hyperinsulinemia, should be associated with an increased risk of breast cancer. A meta-analysis restricted to prospective cohort studies was undertaken using a random effects model with tests for statistical significance, publication bias and heterogeneity. The metric for analysis was the risk of breast cancer in the highest relative to the lowest glycemic index and glycemic load dietary pattern. A dietary pattern with a high glycemic index was associated with a summary relative risk (SRR) of 1.05 (95% CI: 1.00, 1.11), and a high glycemic load with a SRR of 1.06 (95% CI: 1.00, 1.13). Adjustments for body mass index BMI, physical activity and other lifestyle factors did not influence the SRR, nor did menopausal status and estrogen receptor status of the tumor. In conclusion, the current evidence supports a modest association between a dietary pattern with high glycemic index or glycemic load and the risk of breast cancer.
Abstract Introduction : Cancer has become a major source of morbidity and mortality globally. Despite the threat that cancer poses to public health in sub-Saharan Africa (SSA), few countries in this ...region have data on cancer incidence. In this paper, we present estimates of cancer incidence in Nigeria based on data from 2 population-based cancer registries (PBCR) that are part of the Nigerian national cancer registry program. Materials and methods : We analyzed data from 2 population based cancer registries in Nigeria, the Ibadan Population Based Cancer Registry (IBCR) and the Abuja Population Based Cancer Registry (ABCR) covering a 2 year period 2009–2010. Data are reported by registry, gender and in age groups. We present data on the age specific incidence rates of all invasive cancers and report age standardized rates of the most common cancers stratified by gender in both registries. Results : The age standardized incidence rate for all invasive cancers from the IBCR was 66.4 per 100 000 men and 130.6 per 100 000 women. In ABCR it was 58.3 per 100 000 for men and 138.6 per 100 000 for women. A total of 3393 cancer cases were reported by the IBCR. Of these cases, 34% (1155) were seen among males and 66% (2238) in females. In Abuja over the same period, 1128 invasive cancers were reported. 33.6% (389) of these cases were in males and 66.4% (768) in females. Mean age of diagnosis of all cancers in men for Ibadan and Abuja were 51.1 and 49.9 years respectively. For women, mean age of diagnosis of all cancers in Ibadan and Abuja were 49.1 and 45.4 respectively. Breast and cervical cancer were the commonest cancers among women and prostate cancer the most common among men. Breast cancer age standardized incidence rate (ASR) at the IBCR was 52.0 per 100 000 in IBCR and 64.6 per 100 000 in ABCR. Cervical cancer ASR at the IBCR was 36.0 per 100 000 and 30.3 per 100 000 at the ABCR. The observed differences in incidence rates of breast, cervical and prostate cancer between Ibadan and Abuja, were not statistically significant. Conclusion : Cancer incidence data from two population based cancer registries in Nigeria suggests substantial increase in incidence of breast cancer in recent times. This paper highlights the need for high quality regional cancer registries in Nigeria and other SSA countries.
PDF
