Prostate and breast cancer in four Nordic countries: A comparison of incidence and mortality trends across countries and age groups 1975-2013.

In recent decades, management of prostate and breast cancer patients has changed considerably. The purpose of our study is to interpret patterns of prostate and breast cancer incidence and mortality in four Nordic countries across age groups and time periods. Prostate and breast cancer incidence and mortality data (1975-2013) were obtained from the NORDCAN database. Joinpoint regression models were used to identify changes in the trends. A more prominent increase in prostate than breast cancer incidence was observed. From the mid-1990s, mortality rates in patients below 75 years of age have decreased for both cancers in all four countries. The relative decline in breast cancer mortality from 1985-1989 to 2009-2013 were largest in women under 50 years of age, with reductions in mortality rates ranging from 38% in Finland to 55% in Denmark. In the age group 55-74 years, mortality rates for prostate cancer declined more than for breast cancer in all countries except Denmark, ranging from 14% in Denmark to 39% in Norway. The substantial decrease in breast cancer mortality in women below regular screening age and the reductions in mortality from both cancers in Denmark from the mid-1990s are consistent with beneficial contributions from improved treatment besides mammography screening and increased PSA testing. Alongside similar mortality decreases, the larger increases in prostate cancer incidence as compared to breast cancer indicate that a higher proportion of prostate cancer cases are overdiagnosed.

50 years of screening in the Nordic countries: quantifying the effects on cervical cancer incidence.

BACKGROUND: Nordic countries' data offer a unique possibility to evaluate the long-term benefit of cervical cancer screening in a context of increasing risk of human papillomavirus infection. METHODS: Ad hoc-refined age-period-cohort models were applied to the last 50-year incidence data from Denmark, Finland, Norway and Sweden to project expected cervical cancer cases in a no-screening scenario. RESULTS: In the absence of screening, projected incidence rates for 2006-2010 in Nordic countries would have been between 3 and 5 times higher than observed rates. Over 60,000 cases or between 41 and 49% of the expected cases of cervical cancer may have been prevented by the introduction of screening in the late 1960s and early 1970s. CONCLUSIONS: Our study suggests that screening programmes might have prevented a HPV-driven epidemic of cervical cancer in Nordic countries. According to extrapolations from cohort effects, cervical cancer incidence rates in the Nordic countries would have been otherwise comparable to the highest incidence rates currently detected in low-income countries.

Breast cancer survival and stage at diagnosis in Australia, Canada, Denmark, Norway, Sweden and the UK, 2000-2007: a population-based study.

BACKGROUND: We investigate whether differences in breast cancer survival in six high-income countries can be explained by differences in stage at diagnosis using routine data from population-based cancer registries. METHODS: We analysed the data on 257,362 women diagnosed with breast cancer during 2000-7 and registered in 13 population-based cancer registries in Australia, Canada, Denmark, Norway, Sweden and the UK. Flexible parametric hazard models were used to estimate net survival and the excess hazard of dying from breast cancer up to 3 years after diagnosis. RESULTS: Age-standardised 3-year net survival was 87-89% in the UK and Denmark, and 91-94% in the other four countries. Stage at diagnosis was relatively advanced in Denmark: only 30% of women had Tumour, Nodes, Metastasis (TNM) stage I disease, compared with 42-45% elsewhere. Women in the UK had low survival for TNM stage III-IV disease compared with other countries. CONCLUSION: International differences in breast cancer survival are partly explained by differences in stage at diagnosis, and partly by differences in stage-specific survival. Low overall survival arises if the stage distribution is adverse (e.g. Denmark) but stage-specific survival is normal; or if the stage distribution is typical but stage-specific survival is low (e.g. UK). International differences in staging diagnostics and stage-specific cancer therapies should be investigated.

A health economic evaluation of follow-up after breast cancer surgery: results of an rct study.

INTRODUCTION: Breast cancer follow-up programmes consume large resources and despite the indications that several alternative approaches could be used effectively, there is no coherent discussion about costs and/or cost-effectiveness of follow-up programmes. PATIENT AND METHODS: In a prospective trial there were 264 breast cancer patients, stage I and II, randomised to two different follow-up programmes- PG (physician group) and NG (nurse group). The trial period was 5 years. The women in the two intervention groups did not differ in anxiety and depression, their satisfaction with care, their experienced accessibility to the medical centre or their medical outcome as measured by recurrence or death. The analyses were done from different lists representing costs at three hospitals in Sweden according to the principles of a cost minimization study. RESULTS: The cost per person year of follow-up differed between the groups, with 630 euro per person year in PG compared to 495 euro per person year in NG. Thus, specialist nurse intervention with check-ups on demand was 20% less expensive than routine follow-up visits to the physician. The main difference in cost between the groups was explained by the numbers of visits to the physician in the respective study arms. There were 21% more primary contacts in PG than NG. DISCUSSION: The difference in cost per year and patient by study arm is modest, but transforms to nearly 900 euro per patient and 5-year period, offering a substantial opportunity for reallocating resources since breast cancer is the most prevalent tumour worldwide.

The 15-Country Collaborative Study of Cancer Risk among Radiation Workers in the Nuclear Industry: estimates of radiation-related cancer risks.

A 15-Country collaborative cohort study was conducted to provide direct estimates of cancer risk following protracted low doses of ionizing radiation. Analyses included 407,391 nuclear industry workers monitored individually for external radiation and 5.2 million person-years of follow-up. A significant association was seen between radiation dose and all-cause mortality [excess relative risk (ERR) 0.42 per Sv, 90% CI 0.07, 0.79; 18,993 deaths]. This was mainly attributable to a dose-related increase in all cancer mortality (ERR/Sv 0.97, 90% CI 0.28, 1.77; 5233 deaths). Among 31 specific types of malignancies studied, a significant association was found for lung cancer (ERR/Sv 1.86, 90% CI 0.49, 3.63; 1457 deaths) and a borderline significant (P = 0.06) association for multiple myeloma (ERR/Sv 6.15, 90% CI <0, 20.6; 83 deaths) and ill-defined and secondary cancers (ERR/Sv 1.96, 90% CI -0.26, 5.90; 328 deaths). Stratification on duration of employment had a large effect on the ERR/Sv, reflecting a strong healthy worker survivor effect in these cohorts. This is the largest analytical epidemiological study of the effects of low-dose protracted exposures to ionizing radiation to date. Further studies will be important to better assess the role of tobacco and other occupational exposures in our risk estimates.

Reduced mortality for women with mammography-detected breast cancer in east Denmark and south Sweden.

The 5-year relative survival from breast cancer in Denmark is 10 percentage points lower than in Sweden. This difference has been demonstrated previously as being caused partly by more involved lymph nodes and larger tumours in Denmark. Sweden has had nationwide mammography-screening coverage since 1991, whereas this is still in its infancy in Denmark. In the search for an explanation for the remaining survival difference, patient delay was a likely candidate. This study compared patient delay and mammography-detection between two national regions. Data on patient delay and mammography were obtained from hospital records from 1989 and 1994, and analysed using Cox proportional hazard analysis of death within the first 5 years, with the factors age, country, delay/mammography detection and established patho-anatomic variables. A comparison of patient delay and mammography detection in 1989 and 1994 showed more mammography-detected tumours in south Sweden and more women with long delay in east Denmark. Mammography detection, but not long patient delay, had a significant effect on the death hazard when adjusting for patho-anatomic risk factors. The hazard ratio was not eliminated in 1989, but in 1994, the hazard ratio between east Denmark and south Sweden was reduced from 1.3 to 1.1. In conclusion, patient delay did not appear to have any effect on 5-year survival when adjusting for patho-anatomic factors, but tumour detection by mammography affected survival favourably and partly explained the survival difference between east Denmark and south Sweden.

Uveal and conjunctival malignant melanoma in denmark 1943-97: observed and relative survival of patients followed through 2002.

PURPOSE: To evaluate the observed and relative survival of patients diagnosed with a malignant melanoma in the ocular region in Denmark during the period 1943-97. METHODS: The study included 2,504 patients (1,292 men and 1,212 women) diagnosed with a melanoma in the ocular region, of which 2,434 cases could be topographically subclassified into 2,178 in the choroid/ciliary body, 141 in the iris, and 115 in the conjunctiva. The patients were followed through 2002 and the observed survival proportions and relative survival ratios were estimated. RESULTS: For the total ocular region and the choroid/ciliary body, the observed survival did not vary statistically significantly with the year of diagnosis. A statistically insignificant higher observed survival for women than men was found for tumors in the ocular region and the subgroups choroid/ciliary body, iris, and conjunctiva. During the 55-year study period, the 5- and 10-year relative survival remained stable for the ocular region for men at 67% and 57% and for women at 71% and 60%, respectively, and stable for the choroid/ciliary body for men at 66% and 55% and for women at 69% and 57%, respectively. The 5- and 10-year relative survival for the iris was for men 90% and 85% and for women 99% and 101%, respectively, and for the conjunctiva for men 83% and 70% and for women 93% and 82%, respectively. CONCLUSION: The observed and relative survival of patients diagnosed with a melanoma in the ocular region and choroid/ciliary body in Denmark during the period 1943-97 and followed through 2002 has remained stable. The highest observed and relative survival was found for iris melanomas, the lowest for choroid/ciliary body melanomas, and intermediate for conjunctival melanomas.

Smoking and colorectal cancer: a 20-year follow-up study of Swedish construction workers.

BACKGROUND: Although cigarette smoking has consistently been shown to be positively related to the risk of adenomatous polyp development (benign neoplastic growth of epithelial tissue in the colon), most studies of cigarette smoking and the risk of colorectal cancer have been negative. However, in two large prospective studies in women and men, a statistically significant association between cigarette smoking and an increased risk of colorectal cancer was found, but only after more than 35 years of smoking. PURPOSE: To shed further light on the alleged relationship between long-term smoking and colorectal cancer risk, we performed a retrospective cohort study among Swedish construction workers, with many long-term smokers, complete long-term follow-up, and a large number of observed cases. METHODS: We analyzed the association of smoking with colon cancer and with rectal cancer, using data on a cohort of approximately 135000 male construction workers. High-quality exposure information was collected with the use of a comprehensive questionnaire filled out at the time of enrollment in the cohort, from 1971 through 1975. Complete follow-up was achieved through 1991 and the subjects were observed for an average of 17.6 years, thereby contributing approximately 2375000 person-years of follow-up. We calculated age-adjusted rate ratios (RRs) with the use of Poisson-based multiplicative multivariate models followed by further multivariate modeling that adjusted for other variables. RESULTS: A total of 713 incident colon cancers and 505 rectal cancers were observed. There was no statistically significant association between current smoking status, number of cigarettes smoked or number of years smoking, and risk of colorectal cancer. The age-adjusted RRs were 0.98 (95% confidence interval [CI] = 0.82-1.17) and 1.16 (95% CI = 0.94-1.44) for colon and rectal cancers, respectively, among current smokers, and 1.07 (95% CI = 0.63-1.82) and 1.08 (95% CI = 0.58-2.03) among smokers of 25 or more cigarettes per day, relative to nonsmokers. Among smokers for more than 30 years at the start of follow-up, the age-adjusted RRs were 1.03 (95% CI = 0.85-1.25) and 1.21 (95% CI = 0.96-1.53) for colon and rectal cancers, respectively, relative to nonsmokers. Heavy smokers of cigars and pipes had a statistically nonsignificant tendency toward excess risk for colon cancer, but there was no clear dose-risk trend. CONCLUSION: Our large cohort study did not indicate any excess risk of colon cancer in males who were long-term heavy smokers and provided only weak support for an association with rectal cancer. Our data are thus consistent with the majority of previous reports. The reasons for the discrepancies in comparison with recent U.S. data have yet to be identified.

Body size and prostate cancer: a 20-year follow-up study among 135006 Swedish construction workers.

BACKGROUND: Obesity is associated with endocrine changes (e.g., increased estrogen and decreased testosterone in the blood) that have been implicated in the cause of prostate cancer and, therefore, an association between body weight and the risk of developing prostate cancer would be expected. However, because of bias or low statistical power in previous epidemiologic studies, associations between anthropometric measurements (height and weight), body mass index (BMI), and the risk of prostate cancer may have been inadvertently overlooked. PURPOSE: We performed a large, retrospective cohort study among Swedish construction workers to evaluate possible associations of adult weight, height, BMI, and lean body mass (LBM) by age at entry in the study with the incidence and mortality rate of prostate cancer. METHODS: We analyzed data that had been compiled in a computerized central register on a cohort of approximately 135000 male construction workers. Information on height and weight had been collected with the use of a comprehensive questionnaire filled out by nurses at the time of enrollment in the cohort, from 1971 through 1975. Complete follow-up was achieved through 1991 by means of record linkage to the Swedish National Cancer Register, the Death Register, and the Migration Register. A total of 2368 incident cases and 708 deaths from prostate cancer occurred in the cohort during a follow-up period averaging 18 years. We used only information obtained at the index visit from 1971 through 1975 to determine age-adjusted rate ratios (RRs) in a Poisson-based multiplicative multivariate model with age and the relevant exposure variable (e.g., weight, height, BMI, and LBM) as independent variables. RESULTS: All anthropometric measurements were positively associated with the risk of prostate cancer and were more strongly related to mortality than to incidence. The excess risk of death from prostate cancer was statistically significant in all BMI categories above the reference category: RR = 1.40 (95% confidence interval [CI] = 1.09-1.81) in the highest category compared with the lowest (P for trend = .04). For height and LBM, the excess risk in the highest compared with the lowest categories was somewhat less pronounced: RR = 1.28 (95% CI = 1.02-1.60) and RR = 1.26 (95% CI = 1.02-1.57), respectively. Statistically significant linear dose-response relationships were also found with the incidence of prostate cancer, with the exception of BMI (P for trend = .10). CONCLUSION: Our large cohort study indicates that various aspects of body size are related to the risk of prostate cancer and that future studies are needed to study the role of body size and prostate cancer.

Radiation dose and leukemia risk in patients treated for cancer of the cervix.

To quantify the risk of radiation-induced leukemia and provide further information on the nature of the relationship between dose and response, a case-control study was undertaken in a cohort of over 150,000 women with invasive cancer of the uterine cervix. The cases either were reported to one of 17 population-based cancer registries or were treated in any of 16 oncologic clinics in Canada, Europe, and the United States. Four controls were individually matched to each of 195 cases of leukemia on the basis of age and calendar year when diagnosed with cervical cancer and survival time. Leukemia diagnoses were verified by one hematologist. Radiation dose to active bone marrow was estimated by medical physicists on the basis of the original radiotherapy records of study subjects. The risk of chronic lymphocytic leukemia, one of the few malignancies without evidence for an association with ionizing radiation, was not increased [relative risk (RR) = 1.03; n = 52]. However, for all other forms of leukemia taken together (n = 143), a twofold risk was evident (RR = 2.0; 90% confidence interval = 1.0-4.2). Risk increased with increasing radiation dose until average doses of about 400 rad (4 Gy) were reached and then decreased at higher doses. This pattern is consistent with experimental data for which the down-turn in risk at high doses has been interpreted as due to killing of potentially leukemic cells. The dose-response information was modeled with various RR functions, accounting for the nonhomogeneous distribution of radiation dose during radiotherapy. The local radiation doses to each of 14 bone marrow compartments for each patient were incorporated in the models, and the corresponding risks were summed. A good fit to the observed data was obtained with a linear-exponential function, which included a positive linear induction term and a negative exponential term. The estimate of the excess RR per rad was 0.9%, and the estimated RR at 100 rad (1 Gy) was 1.7. The model proposed in this study of risk proportional to mass exposed and of risk to an individual given by the sum of incremental risks to anatomic sites appears to be applicable to a wide range of dose distributions. Furthermore, the pattern of leukemia incidence associated with different levels of radiation dose is consistent with a model postulating increasing risk with increasing exposure, modified at high doses by increased frequency of cell death, which reduces risk.

Effect of organized screening on incidence and mortality of cervical cancer in Denmark.

Pap smears were used only on a limited scale in Denmark until the late 1960s. Since then smears have been taken both in organized screening programs and outside the programs by general practitioners, private gynecologists, and hospital wards. The present smear-taking activity is equivalent to an average of one smear every second year per woman. As the responsibility for health care rests with the counties in Denmark, differences are found between the counties both concerning organization of screening programs, and concerning the overall level of the smear-taking activity. An analysis using multiplicative Poisson models on county-based incidence and mortality data for women aged 30-59 years in 1963-1982 showed a statistically significant effect of organized screening in reducing both the incidence (RR = 0.67; 95% CI, 0.61-0.73), and the mortality (RR = 0.68; 95% CI, 0.59-0.78) of cervical cancer from 5 years after introduction of an organized screening program. The level of overall smear-taking activity was found to be of limited importance when organized screening was taken into account.

Uveal and conjunctival malignant melanoma in Denmark, 1943-97: incidence and validation study.

PURPOSE: To study the incidence of malignant melanoma in the ocular region in Denmark during the period 1943-97. METHODS: The patients were mainly identified through the Danish Cancer Registry. Age-period-cohort modelling of the incidence rates was done based on age at diagnosis, calendar period and birth cohort in 5-year groups and for each gender. RESULTS: The age-standardized incidence of malignant melanoma in the ocular region was 0.78 for men (N = 1327) and 0.65 for women (N = 1242) per 100,000 person-years. Calendar period and birth cohort had no effect on the incidence in the ocular region or in the topography subgroups choroid/ciliary body and conjunctiva. However, the incidence increased with birth cohort for iris melanomas. CONCLUSIONS: The incidence of malignant melanoma in the ocular region was stable in contrast to a major increase in cutaneous melanoma in Denmark during the period 1943-97. The incidence of iris melanomas increased substantially, whereas the rate was stable for choroid/ciliary body and conjunctival melanomas.

Incident thromboembolism in the aorta and the renal, mesenteric, pelvic, and extremity arteries after discharge from the hospital with a diagnosis of atrial fibrillation.

BACKGROUND: The impact of atrial fibrillation (AF) on risk of peripheral arterial thromboembolism is unknown. METHODS: We analyzed the risk of thromboembolism (embolus and/or thrombosis) in the aorta and the renal, mesenteric, pelvic, and extremity arteries in a cohort of patients discharged from the hospital with an incident diagnosis of AF relative to the risk of thromboembolism in these vessels in the Danish population. In a random sample of half of the Danish population, 14 917 men and 14 945 women aged 50 to 89 years were identified in the Danish National Hospital Discharge Register with a diagnosis of AF from January 1, 1980, through December 31, 1993. Patients were followed up from diagnosis of AF in the Danish National Hospital Discharge Register and the Causes of Death Register until the first diagnosis of a thromboembolic event, death, or the end of 1993. Risk of a thromboembolic event relative to the risk in the Danish population was analyzed by means of Poisson regression modeling. RESULTS: Patients with a hospital diagnosis of AF had an increased risk of thromboembolic events in the aorta and the renal, mesenteric, pelvic, and extremity arteries (relative risk, 4.0 [95% confidence interval, 3.5-4.6] in men; and relative risk, 5.7 [95% confidence interval, 5.1-6.3] in women) compared with the Danish population. CONCLUSION: A hospital diagnosis of AF is an important risk factor for peripheral arterial thromboembolic complications.

Determinants for genital human papillomavirus (HPV) infection in 1000 randomly chosen young Danish women with normal Pap smear: are there different risk profiles for oncogenic and nononcogenic HPV types?

Most studies of risk factors for human papillomavirus (HPV) DNA detection have focused on overall HPV positivity and have not examined determinants for high-risk and low-risk HPV types separately. We studied risk determinants for genital HPV infection in 1000 randomly chosen women (20-29 years) with normal cervical cytology from Copenhagen, Denmark. All women had a personal interview, a Pap smear, and cervical swabs for HPV DNA detection using a PCR technique. On the basis of their association with cervical cancer, the HPV types were categorized as belonging to a high-risk group ("oncogenic types") or a low-risk group ("nononcogenic types"). The overall HPV detection rate was 15.4%. Of HPV-positive women, 74% had oncogenic HPV types, and 30% had nononcogenic HPV types. Younger age and lifetime measures of sexual activity (notably, number of partners) were the main risk factors for the oncogenic HPV types. Furthermore, a previous Chlamydia infection was associated with the high-risk HPV types. In contrast, the most important determinants for nononcogenic HPV infection were contraceptive variables related to the physical protection of the cervix (condom or diaphragm) and number of partners in the last 4 or 12 months. Our study confirms the venereal nature of HPV infection. We hypothesize that the low-risk HPV infection, which correlates with recent sexual behavior, may be more transient than infection with the oncogenic HPV types, which correlates with lifetime exposure measurements of sexual habits.

Can the survival difference between breast cancer patients in Denmark and Sweden 1989 and 1994 be explained by patho-anatomical variables?--a population-based study.

Analyses of data from cancer registries have shown a 10% unit difference in 5-year relative survival between Danish and Swedish patients with breast cancer. This study investigates the effect of age and patho-anatomic variables on this survival difference. Hospital records were collected for women over 40 years of age diagnosed in 1989 or 1994 in east Denmark and south Sweden; patho-anatomical variables and survival were compared between 2289 Danish and 1715 Swedish women. Tumours were smaller, node-negative axillae more frequent and well-differentiated tumours almost 10% more frequent in Sweden. A superior 5-year relative survival in Sweden was found in the 50- to 79-year age group. The adjusted hazard rate ratio between countries was 1.7 in 1989 and 1.3 in 1994. Conditional survival after surviving the first 5 years was similar for the two countries. Adjusting for patho-anatomical variables reduced but did not eliminate the higher risk of death among the Danish patients. Higher population death rates could explain some but not all of the residual elevated risk for Danish women.

Incident stroke after discharge from the hospital with a diagnosis of atrial fibrillation.

PURPOSE: Atrial fibrillation is an important risk factor for stroke. We analyzed stroke risk over time in patients discharged from the hospital with a diagnosis of incident atrial fibrillation as compared with the risk of stroke in the Danish population. SUBJECTS AND METHODS: In a random sample of half of the Danish population, we identified 13,625 men and 13,577 women, aged 50 to 89 years, with a hospital diagnosis of atrial fibrillation and no prior diagnosis of stroke during 1980 to 1993. Data on other medical conditions were also available from 1977 to 1993, but medication data were not available. Patients were followed from the diagnosis of atrial fibrillation until the first diagnosis of stroke (nonfatal or fatal cerebral ischemic infarct and cerebral hemorrhage), death, or the end of 1993. The risk of stroke in these patients was compared with the risk in the Danish population using Poisson regression modeling to estimate relative risks (RR) and 95% confidence intervals (CI). RESULTS: For men with atrial fibrillation, the stroke rates increased by age, from 13 per 1,000 person-years in those ages 50 to 59 years, to 22 per 1,000 person-years in those ages 60 to 69 years, to 42 per 1,000 person-years in those ages 70 to 79 years, to 51 per 1,000 person-years in those ages 80 to 89 years. Age-specific stroke rates were similar in women with atrial fibrillation. Patients with a hospital diagnosis of atrial fibrillation had an increased risk of stroke (RR = 2.4; 95% CI, 2.3 to 2.5 in men and RR = 3.0; 95% CI, 2.9 to 3.2 in women) compared with the Danish population. Stroke risk was greatest during the first year after discharge and decreased thereafter. Hypertension, diabetes, and peripheral atherosclerosis were also associated with an increased risk of stroke among patients with atrial fibrillation. Ischemic heart disease and heart failure were risk factors in men only. There was no reduction in the risk of stroke from 1980 to 1993. CONCLUSIONS: Men and women with atrial fibrillation are at a substantially increased risk of stroke, particularly in the first year after the diagnosis.

Mortality and cancer morbidity in a group of Swedish VCM and PCV production workers.

The cohort of workers employed in a Swedish vinyl chloride/poly(vinyl chloride) plant since its start in the early 1940's has been followed for mortality and cancer morbidity patterns. Only 21 of the 771 persons could not be traced. Difficulties in establishing exposure levels at different work areas in the past makes an evaluation of dose-effect relationships impossible. A four- to fivefold excess of pancreas/liver tumors was found, including two cases later classified as angiosarcomas of the liver. The number of brain tumors and suicide do not deviate significantly from expected. Cardiovascular and cerebrovascular diseases, on the other hand, differ significantly from the expected. The discrepancies between previous reports on VCM/PVC workers and this report are discussed. The possible etiology of the cardiovascular deaths is also discussed.

Trends in cutaneous malignant melanoma in Denmark 1943-1982 by anatomic site.

Time trends in the incidence of cutaneous malignant melanoma were examined by analysing data from the Danish Cancer Registry, 1943-1982, by sex and subsite for 3509 male and 5305 female cases. The age-standardized incidence rate for cutaneous malignant melanoma for men and women in Denmark increased by five- to six-fold between 1943 and 1982. The increase varied by site; a particularly pronounced elevation was seen for tumours of the trunk in both men and women and of the leg in women. A statistical analysis of the effects of age, time and cohort showed steep increases in risk for progressively younger birth cohorts. This association was particular pronounced for sites other than the face, scalp and neck; for the latter sites, there was a much smaller increase for younger cohorts.

The risk of lung cancer from asbestos among Swedish construction workers: self-reported exposure and a job exposure matrix compared.

A total of 719 lung cancers were identified in a follow-up of 135,000 Swedish construction workers interviewed during 1971-1974 by occupational health nurses as part of a routine health check-up. These were analysed in a matched case-control study nested within this cohort, to compare different methods of characterizing exposure to asbestos. Self-reported exposure was contrasted with a job exposure matrix (JEM) of five levels of exposure intensity, applied to the job at the time of health check-up. Smoking adjusted odds ratios were computed and the JEM performed better than self-reported exposure, in being able to discriminate high risk subgroups. The same pattern was evident in a parallel analysis of 41 mesotheliomas. However both measures appeared subject to misclassification, and the question put seemed to pick up the use of asbestos cement products more effectively than asbestos insulation products. It is concluded that a simple JEM can be more reliable than a simple question, but that both should be much more detailed, to take account of different types of asbestos exposure and their variation over time.

Risk factors for renal cell carcinoma in Denmark: role of medication and medical history.

BACKGROUND: Several recent studies of risk factors for renal cell carcinoma have indicated that use of diuretics may increase risk of this cancer. It has also been suggested that use of weak analgesics, which are known to increase risk of cancer of the renal pelvis and ureter, may also be associated with an increased risk of renal cell carcinoma--the most frequent type of kidney cancer. METHODS: A population-based case-control study was undertaken to investigate the role of diuretics, other anti-hypertensive drugs, analgesics, and medical history in the aetiology of renal cell carcinoma. The study base was the total Danish population, and 368 histologically verified cases and 396 sex- and age-matched controls who were interviewed from February 1989 to May 1992. RESULTS: Response rates were 76% among cases and 79% among controls. We found no general increase in risk among users of diuretics or analgesics, although women taking loop diuretics and heavy users of acetyl salicylic acid had slightly increased risks. The use of nondiuretic anti-hypertensive medications was associated with decreased risk in women. We found non-significantly increased risks for history of hypertension and other cardiovascular disorders. We also observed elevated risks for urological disorders in both sexes which may be a result of recall bias. CONCLUSION: This study provides only limited support for the suggested association between risk of renal cell carcinoma and use of diuretics and analgesics. The coexistence of renal cell carcinoma and cardiovascular diseases could be caused by risk factors that are common to these conditions.