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Objective: To determine the incidence and occupational variation of granulosa cell tumours (GCTs) in Finland, Iceland, Norway and Sweden over a 60-year period, 1953-2012.Design: A longitudinal cohort study.Setting and Population: Finland, Iceland, Norway and Sweden and a total of 249 million women over a 60-year period (1953-2012). The NOCCA (Nordic Occupational Cancer Study) included 6.4 million women with 776 incident GCT cases diagnosed until the end of follow up.Methods: Incidence rates were calculated from the national cancer registries and compared using quasi-Poisson regression models. Occupation-specific standardised incidence ratios (SIRs) were calculated from the Nordic Occupational Cancer (NOCCA) database.Main Outcome Measures: Incidence rates and standardised incidence ratios.Results: The age-adjusted (World Standard) incidence rates remained quite constant: about 0.6-0.8 per 100 000 for most of the study period. The age-specific incidence was highest at 50-64 years of age. There were no occupations with significantly increased risk of GCT. Major changes in the use of oral contraceptives, postmenopausal hormonal therapy, fertility rate and lifestyle in general during the study period and among different occupational categories do not appear to have a marked effect on the incidence of GCT.Conclusion: Our findings support the concept of GCT as a primarily sporadic, not exposure-related, cancer.Tweetable Abstract: The Nordic incidence rates of GCTs show stability over time and among different occupational categories. [ABSTRACT FROM AUTHOR]

Knowledge of cancer risk according to occupational affiliation is an essential part of formatting preventive actions aimed at the adult population. Herein, data on 10 major cancer sites amenable by life style exposures from the Nordic Occupational Cancer Study (NOCCA) are presented. All subjects aged 30–64 years participating in one or more national censuses in Denmark, Finland, Iceland, Norway, or Sweden between 1960 and 1990 were included in the cohort and followed up for cancer from inclusion until 2003/2005 via a linkage with the national cancer registries, and standardised incidence ratios (SIRs) were computed. Variation in risk across occupations was generally larger in men than in women. In men, the most consistent cluster with high risk of numerous cancer types included waiters, cooks and stewards, beverage workers, seamen, and chimney sweeps. Two clusters of occupations with generally low cancer risks were seen in both men and women. The first one comprised farmers, gardeners, and forestry workers, the second one included groups with high education, specifically those in health and pedagogical work. Although cancer risk varies by occupation, only a smaller part of the variation can be attributed to occupational exposures in the strict sense. Preventive measures at the work place are important to avoid established and new occupational health hazards. This study also indicates that the work place in addition should be seen as a useful arena for reaching groups of adults with more or less similar habits and attitudes for general health promotion. [Copyright &y& Elsevier]

Background and Purpose: Changes in treatment approaches, characterised by the shift from laryngectomy to a focus on organ-preserving methods may have potentially resulted in lower survival. We aim to identify differences in survival trends for laryngeal cancer (LC) in the Nordic countries over a period of 50 years, and discuss the potential impact of factors such as changes in treatment protocols., Materials and Methods: Five-year relative survival (RS) data from 1972 to 2021 were obtained from the NORDCAN database 2.0 which included 33,692 LC cases, of which 85% were diagnosed among men. In the NORDCAN database, the age-standardised RS is calculated using the Pohar Perme estimator with individual International Cancer Survival Standards weights. Joinpoint regression models were used to assess potential shifts in trend over the years in RS., Results: While Denmark and Norway demonstrated an increasing trend in 5-year RS from 1972 to 2021, in Finland and Sweden, the 5-year RS among men remained static, without any discernible significant trend. Over the 30-year period from 1992-1996 to 2017-2021, RS improved by 9, 4, 13, and 2 percentage points in Denmark, Finland, Norway, and Sweden, respectively. Among women in Sweden, a linear negative trend was observed, noticeable as a 16 percentage-point decline in 5-year RS from the earliest to the latest period., Interpretation: The underlying causes for the differences in survival trends remain unclear. Besides differences in treatment protocols, several other factors can affect RS making the interpretation of RS trends challenging.

Objective: We assessed the association between parental prenatal exposures in wood-related jobs and risk of testicular germ cell tumours (TGCT) in offspring., Methods: NORD-TEST, a registry-based case-control study in Sweden, Finland and Norway, included 8112 TGCT cases diagnosed at ages 14-49 years between 1978 and 2012 with no history of prior cancer, and up to four controls matched to each case on year and country of birth. Parents of cases and controls were identified via linkages with the population registries and their occupational information was retrieved from censuses. The Nordic Occupational Cancer Study Job-Exposure Matrix was used to assign occupational exposures to each parent. Logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI)., Results: Maternal wood-related job was not associated with the risk of TGCT in offspring (OR 1.08, CI 0.55-2.14), while paternal wood-related job was associated with a decreased risk of TGCT in offspring (OR 0.85, CI 0.75-0.96). None of the specific wood-related jobs, such as upholsterers, sawyers, or construction carpenters, were significantly associated with a risk of TGCT. Only exception was observed in a sensitivity analysis which showed an increased risk in the small group of sons of fathers working as 'cabinetmakers and joiners' the year before conception (OR of 2.06, CI 1.00-4.25)., Conclusion: This large-scale NORD-TEST analysis provided no evidence of an association between parental prenatal exposures in wood-related jobs and TGCT in sons., (© 2021. The Author(s).)

Background: The age-adjusted incidence of cutaneous melanoma (CM) in the Nordic countries has increased during the last 60 years. Few prospective population-based studies have estimated the occupational variation in CM risk over time., Objectives: To determine occupational variation in CM risk., Methods: A historical prospective cohort study with a 45-year follow-up from 1961 to 2005 (Nordic Occupational Cancer Study, NOCCA) based on record linkages between census and cancer registry data for Nordic residents aged 30-64 years in Denmark, Finland, Iceland, Norway and Sweden. National occupational codes were converted to 53 occupational categories, and stratified into indoor, outdoor and mixed work, and into socioeconomic status. The standardized incidence ratios (SIRs) were estimated as observed number of CM cases divided by the expected number calculated from stratum-specific person-years and national CM incidence rates., Results: During a follow-up of 385 million person-years, 83 898 incident cases of CM were identified. In all countries combined, men with outdoor work had a low SIR of 0·79 [95% confidence interval (CI) 0·77-0·81] and men with indoor work had a high SIR of 1·09 (95% CI 1·07-1·11). Differences in women pointed in the same direction. High socioeconomic status was associated with an excess risk: SIR 1·34 (95% CI 1·28-1·40) in men and SIR 1·31 (95% CI 1·26-1·36) in women. Technical, transport, military and public safety workers with potential skin exposure to carcinogens had excess risks., Conclusions: Occupational variation in CM risk may be partly explained by host, socioeconomic and skin exposure factors. Differences in CM risk across socioeconomic groups attenuated slightly over time., (© 2020 British Association of Dermatologists.)

Kidney transplant recipients (KTRs) have an increased cancer risk compared to the general population, but absolute risks that better reflect the clinical impact of cancer are seldom estimated. All KTRs in Sweden, Norway, Denmark, and Finland, with a first transplantation between 1995 and 2011, were identified through national registries. Post-transplantation cancer occurrence was assessed through linkage with cancer registries. We estimated standardized incidence ratios (SIR), absolute excess risks (AER), and cumulative incidence of cancer in the presence of competing risks. Overall, 12 984 KTRs developed 2215 cancers. The incidence rate of cancer overall was threefold increased (SIR 3.3, 95% confidence interval [CI]: 3.2-3.4). The AER of any cancer was 1560 cases (95% CI: 1468-1656) per 100 000 person-years. The highest AERs were observed for nonmelanoma skin cancer (838, 95% CI: 778-901), non-Hodgkin lymphoma (145, 95% CI: 119-174), lung cancer (126, 95% CI: 98.2-149), and kidney cancer (122, 95% CI: 98.0-149). The five- and ten-year cumulative incidence of any cancer was 8.1% (95% CI: 7.6-8.6%) and 16.8% (95% CI: 16.0-17.6%), respectively. Excess cancer risks were observed among Nordic KTRs for a wide range of cancers. Overall, 1 in 6 patients developed cancer within ten years, supporting extensive post-transplantation cancer vigilance., (© 2020 The Authors. Transplant International published by John Wiley & Sons Ltd on behalf of Steunstichting ESOT.)

Purpose: Obesity increases the risk of several cancers, but the influence of bariatric surgery on the risk of individual obesity-related cancers is unclear. This study aimed to assess the impact of bariatric surgery on cancer risk in a multi-national setting., Materials and Methods: This cohort study included all adults with an obesity diagnosis identified from national patient registries in all Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) from 1980 to 2012. Cancer risk in bariatric surgery patients was compared with non-operated patients with obesity. Multivariable Cox regression provided adjusted hazard ratios (HRs) with 95% confidence intervals (CIs). Age, sex, calendar year, country, length of follow-up, diabetes, chronic obstructive pulmonary disease and alcohol-related diseases were evaluated as confounders., Results: Among 482,572 participants with obesity, 49,096 underwent bariatric surgery. Bariatric surgery was followed by a decreased overall cancer risk in women (HR 0.86, 95% CI 0.80-0.92), but not in men (HR 0.98, 95% CI 0.95-1.01). The risk reduction was observed only within the first five post-operative years. Among specific tumours, HRs decreased for breast cancer (HR 0.81, 95% CI 0.69-0.95), endometrial cancer (HR 0.69, 95% CI 0.56-0.84) and non-Hodgkin lymphoma (HR 0.64, 95% CI 0.42-0.97) in female bariatric surgery patients, while the risk of kidney cancer increased in both sexes (HR 1.44, 95% CI 1.13-1.84)., Conclusion: Bariatric surgery may decrease overall cancer risk in women within the first five years after surgery. This decrease may be explained by a decreased risk of breast and endometrial cancer and non-Hodgkin lymphoma in women.

Obesity is a risk factor for colorectal cancer. Yet, some research indicates that weight-reducing bariatric surgery also increases colorectal cancer risk. Our study was undertaken because current evidence examining bariatric surgery and risk of colorectal cancer is limited and inconsistent. This population-based cohort study included adults with a documented obesity diagnosis in Denmark, Finland, Iceland, Norway or Sweden in 1980-2015. The incidence of colorectal cancer in participants with obesity who had and had not undergone bariatric surgery was compared to the incidence in the corresponding background population by calculating standardized incidence ratios (SIR) with 95% confidence intervals (CI). Additionally, operated and nonoperated participants with obesity were compared using multivariable Cox regression, providing hazard ratios (HR) with 95% CIs adjusted for confounders. Among 502,772 cohort participants with an obesity diagnosis, 49,931(9.9%) underwent bariatric surgery. The overall SIR of colon cancer was increased after bariatric surgery (SIR 1.56; 95% CI 1.28-1.88), with higher SIRs ≥10 years postsurgery. The overall HR of colon cancer in operated compared to nonoperated participants was 1.13 (95% CI 0.92-1.39) and 1.55 (95% CI 1.04-2.31) 10-14 years after bariatric surgery. Bariatric surgery did not significantly increase the risk of rectal cancer (SIR 1.14, 95% CI 0.83-1.52; HR 1.08, 95% CI 0.79-1.49), but the risk estimates increased with longer follow-up periods. Our study suggests that bariatric surgery is associated with an increased risk of colon cancer, while the support for an increased risk of rectal cancer was weaker., (© 2019 UICC.)

Background: Evidence suggests that among some occupational groups, there is an elevated risk of kidney cancer. This might, however, derive from a difference in smoking habits across occupational groups. The objective of this study was to determine smoking-adjusted occupational variation in the incidence of kidney cancer in Nordic males. Material and Methods: The source population for this study consisted of 7.4 million men from Denmark, Iceland, Finland, Norway, and Sweden. Data on occupation were obtained from national censuses conducted in the years 1960-1990. Data on cancer cases came from national cancer registries. A proxy for the occupation-specific smoking prevalence among all Nordic men was calculated based on the occupation-specific smoking prevalence and lung cancer incidence data for Finnish men. Smoking-adjusted standardized incidence ratio (SIR adj ) with 95% confidence intervals (95%CI) were calculated for each occupational group. Results: The highest SIR adj estimates were observed in dentists (1.32, 95%CI 1.06-1.62), journalists (1.20, 95%CI 1.00-1.42), physicians (1.19, 95%CI 1.03-1.36), public safety workers (1.18, 95%CI 1.10-1.26), administrators (1.17, 95%CI 1.13-1.22), military personnel (1.16, 95%CI 1.05-1.28), and religious workers (1.17, 95%CI 1.09-1.26). The lowest SIR adj was observed among forestry workers (0.82, 95%CI 0.76-0.88). Conclusions: Tobacco smoking plays an important role in the occupational variation in the risk of kidney cancer. The smoking-adjusted incidence of kidney cancer was increased in dentists, physicians, journalists, administrators, and public safety workers.

Background & Aims: Bariatric surgery might reduce overall mortality from obesity. We investigated whether the survival times of patients who have had bariatric surgery are similar to those of the general population and are longer than of obese individuals who did not receive surgery., Methods: We performed a population-based cohort study of persons with a diagnosis of obesity listed in nationwide registries from Nordic countries from 1980 through 2012. Bariatric surgery was analyzed in relation to all-cause mortality and the obesity-related morbidities cardiovascular disease, diabetes, cancer, and suicide. Poisson models provided standardized mortality ratios (SMRs) with 95% confidence intervals (CIs). Multivariable Cox regression provided hazard ratios (HRs) for mortality in participants who did and did not have surgery., Results: Among 505,258 participants, 49,977 had bariatric surgery. Overall all-cause SMR was increased after surgery (1.94; 95% CI, 1.83-2.05) and increased with longer follow-up, to 2.28 (95% CI, 2.07-2.51) at ≥15 years after surgery. SMRs were increased for cardiovascular disease (2.39; 95% CI, 2.17-2.63), diabetes (3.67; 95% CI, 2.85-4.72), and suicide (2.39; 95% CI, 1.96-2.92) but not for cancer (1.05; 95% CI, 0.95-1.17); SMRs increased with time. In obese participants who did not have surgery, all-cause SMR was 2.15 (95% CI, 2.11-2.20), which remained stable during follow-up. Compared with obese participants who did not have surgery, patients who had bariatric surgery had decreased overall mortality from all causes (HR, 0.63; 95% CI, 0.60-0.66), cardiovascular disease (HR, 0.57; 95% CI, 0.52-0.63), and diabetes (HR, 0.38; 95% CI, 0.29-0.49) but increased mortality from suicide (HR, 1.68; 95% CI, 1.32-2.14). Cancer mortality was decreased overall (HR, 0.84; 95% CI, 0.76-0.93) but increased at ≥15 years of follow-up (HR, 1.20; 95% CI, 1.02-1.42)., Conclusions: In a study of persons with a diagnosis of obesity listed in nationwide registries of Nordic countries, we found that obese patients who have bariatric surgery have longer survival times than obese individuals who did not have bariatric surgery, but their mortality is higher than that of the general population and increases with time. Obesity-related morbidities could account for these findings., (Copyright © 2019 AGA Institute. Published by Elsevier Inc. All rights reserved.)

The Nordic countries have comprehensive, population-based health and medical registries linkable on individually unique personal identity codes, enabling complete long-term follow-up. The aims of this study were to describe the NorTwinCan cohort established in 2010 and assess whether the cancer mortality and incidence rates among Nordic twins are similar to those in the general population. We analyzed approximately 260,000 same-sexed twins in the nationwide twin registers in Denmark, Finland, Norway and Sweden. Cancer incidence was determined using follow-up through the national cancer registries. We estimated standardized incidence (SIR) and mortality (SMR) ratios with 95% confidence intervals (CI) across country, age, period, follow-up time, sex and zygosity. More than 30,000 malignant neoplasms have occurred among the twins through 2010. Mortality rates among twins were slightly lower than in the general population (SMR 0.96; CI 95% [0.95, 0.97]), but this depends on information about zygosity. Twins have slightly lower cancer incidence rates than the general population, with SIRs of 0.97 (95% CI [0.96, 0.99]) in men and 0.96 (95% CI [0.94, 0.97]) in women. Testicular cancer occurs more often among male twins than singletons (SIR 1.15; 95% CI [1.02, 1.30]), while cancers of the kidney (SIR 0.82; 95% CI [0.76, 0.89]), lung (SIR 0.89; 95% CI [0.85, 0.92]) and colon (SIR 0.90; 95% CI [0.87, 0.94]) occur less often in twins than in the background population. Our findings indicate that the risk of cancer among twins is so similar to the general population that cancer risk factors and estimates of heritability derived from the Nordic twin registers are generalizable to the background populations.

Objective: The aim of this study was to describe the occupational variation in the incidence of kidney cancer in the Nordic population., Methods: The population comprised of 14.9 million individuals included in censuses between 1960 and 1990. Standardized incidence ratios (SIRs) were calculated for each occupational group., Results: Significantly increased SIRs were observed in welders [1.24, 95% confidence interval (95% CI) 1.14 to 1.35], public safety workers (1.16, 95% CI 1.08 to 1.25), and seamen (1.16, 95% CI 1.07 to 1.26). Significantly decreased SIRs were found in laboratory assistants (0.76, 95% CI 0.60 to 0.94) and forestry workers (0.77, 95% CI 0.72 to 0.83)., Conclusion: A relatively small variation in the incidence of malignancies of the kidney between occupational groups was found in the cohort. There is abundant room for further progress in determining the effect of smoking in particular occupational groups.

Objectives: To assess the association between occupational exposure to asbestos and the risk of cholangiocarcinoma (CC)., Methods: We conducted a case-control study nested in the Nordic Occupational Cancer (NOCCA) cohort. We studied 1458 intrahepatic CC (ICC) and 3972 extrahepatic CC (ECC) cases occurring among subjects born in 1920 or later in Finland, Iceland, Norway and Sweden. Each case was individually matched by birth year, gender and country to five population controls. The cumulative exposure to asbestos (measured in fibres (f)/ml × years) was assessed by applying the NOCCA job-exposure matrix to data on occupations collected during national population censuses (conducted in 1960, 1970, 1980/81 and 1990). Odds ratios (OR) and 95% CI were estimated using conditional logistic regression models adjusted by printing industry work., Results: We observed an increasing risk of ICC with cumulative exposure to asbestos: never exposed, OR 1.0 (reference category); 0.1-4.9 f/mL × years, OR 1.1 (95% CI 0.9 to 1.3); 5.0-9.9 f/mL × years, OR 1.3 (95% CI 0.9 to 2.1); 10.0-14.9 f/mL × years, OR 1.6 (95% CI 1.0 to 2.5); ≥15.0 f/mL × years, OR 1.7 (95% CI 1.1 to 2.6). We did not observe an association between cumulative asbestos exposure and ECC., Conclusions: Our study provides evidence that exposure to asbestos might be a risk factor for ICC. Our findings also suggest that the association between ECC and asbestos is null or weaker than that observed for ICC. Further studies based on large industrial cohorts of asbestos workers and possibly accounting for personal characteristics and clinical history are needed., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Importance: Estimates of familial cancer risk from population-based studies are essential components of cancer risk prediction., Objective: To estimate familial risk and heritability of cancer types in a large twin cohort., Design, Setting, and Participants: Prospective study of 80,309 monozygotic and 123,382 same-sex dizygotic twin individuals (N = 203,691) within the population-based registers of Denmark, Finland, Norway, and Sweden. Twins were followed up a median of 32 years between 1943 and 2010. There were 50,990 individuals who died of any cause, and 3804 who emigrated and were lost to follow-up., Exposures: Shared environmental and heritable risk factors among pairs of twins., Main Outcomes and Measures: The main outcome was incident cancer. Time-to-event analyses were used to estimate familial risk (risk of cancer in an individual given a twin's development of cancer) and heritability (proportion of variance in cancer risk due to interindividual genetic differences) with follow-up via cancer registries. Statistical models adjusted for age and follow-up time, and accounted for censoring and competing risk of death., Results: A total of 27,156 incident cancers were diagnosed in 23,980 individuals, translating to a cumulative incidence of 32%. Cancer was diagnosed in both twins among 1383 monozygotic (2766 individuals) and 1933 dizygotic (2866 individuals) pairs. Of these, 38% of monozygotic and 26% of dizygotic pairs were diagnosed with the same cancer type. There was an excess cancer risk in twins whose co-twin was diagnosed with cancer, with estimated cumulative risks that were an absolute 5% (95% CI, 4%-6%) higher in dizygotic (37%; 95% CI, 36%-38%) and an absolute 14% (95% CI, 12%-16%) higher in monozygotic twins (46%; 95% CI, 44%-48%) whose twin also developed cancer compared with the cumulative risk in the overall cohort (32%). For most cancer types, there were significant familial risks and the cumulative risks were higher in monozygotic than dizygotic twins. Heritability of cancer overall was 33% (95% CI, 30%-37%). Significant heritability was observed for the cancer types of skin melanoma (58%; 95% CI, 43%-73%), prostate (57%; 95% CI, 51%-63%), nonmelanoma skin (43%; 95% CI, 26%-59%), ovary (39%; 95% CI, 23%-55%), kidney (38%; 95% CI, 21%-55%), breast (31%; 95% CI, 11%-51%), and corpus uteri (27%; 95% CI, 11%-43%)., Conclusions and Relevance: In this long-term follow-up study among Nordic twins, there was significant excess familial risk for cancer overall and for specific types of cancer, including prostate, melanoma, breast, ovary, and uterus. This information about hereditary risks of cancers may be helpful in patient education and cancer risk counseling.

Background: We aimed to estimate lifetime cumulative risk of melanoma (CRM) in relatives of patients with melanoma by histology and age at diagnosis in patients and relatives., Methods: A population-based cohort of 238724 first-degree relatives of 46091 melanoma patients diagnosed in 1955-2010 in Nordic countries was followed for cancer incidence., Findings: The CRM (0-79 years) in first-degree relatives of a patient with superficial spreading (SSM), nodular (NM), or lentigo maligna melanoma was quite similar, ranging from 2.5% to about 3%, which represents about 2-fold increase over the general population risk. When one melanoma patient in the family was diagnosed before age 30, the CRM was about 3%. When there were > or =2 melanoma patients diagnosed before age 30 in a family, CRM for relatives was about 14%, 6% for diagnoses at age 30-59, and 5% for diagnoses at age 60 or older. Depending on age at diagnosis of same-sex twins (not known whether monozygotic/dizygotic), their CRM was about 7-21%. Although no familial case of concordant histological types of acral lentiginous/desmoplastic/compound nevus/spindle cell melanomas or malignant blue nevus was found, familial risks of discordant histological types of melanoma were interchangeably high for most of the types, e.g. higher risk of SSM when a first-degree relative had NM [standardized incidence ratios (SIR)=2.6, 95% confidence interval (CI)=2.1-3.3, n=72] or acral lentiginous (4.0, 95% CI=1.5-8.8, n=6) and vice versa. There was a tendency toward concordant age at diagnosis of melanoma among relatives of melanoma patients., Interpretation: Findings of this study may help clinicians to find subjects at high melanoma risk for the genetic counseling. The risk was highest when melanoma occurred in a same-sex twin, one first-degree relative diagnosed at young age (<30), or > or =2 first-degree relatives. Histological type of melanoma does not seem to play an important role in familial melanoma., Funding: This work was supported by the Nordic Cancer Union, Swedish Council for Working Life and Social Research, and German Cancer Aid., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Survival after non-Hodgkin lymphoma (NHL) has increased thanks to improved treatment but NHL survivors have an increased risk of second neoplasms. The assessment of cancer risk patterns after NHL may help to quantify the late side-effects of therapy. Poisson regression was used to estimate relative risks (RRs) and absolute incidence rates for nine solid tumours based on a nationwide cohort of 60 901 NHL survivors from Finland, Norway and Sweden. Patients were diagnosed between 1980 and 2006 and developed 6815 s neoplasms. NHL patients showed an increased risk of each of the nine investigated cancer sites: prostate and pancreas (both RRs 1·28), breast (1·37), colorectum (1·48), urinary bladder (1·52), stomach and lung (both RRs 1·87), skin (melanoma 2·27) and kidney (2·56). The RRs showed a U-shaped relationship with time after NHL for all nine-second cancer types. NHL diagnosis early in life was a risk factor for the development of second cancers with the exception of melanoma, but a risk excess was even observed in patients diagnosed with NHL at age 80+ years. The present study provides accurate estimates on the adverse late effects of NHL therapy, which should guide the establishment of cancer prevention strategies in NHL survivors., (© 2013 John Wiley & Sons Ltd.)

Objectives and Study Design: Uterine sarcomas are an uncommon and heterogeneous group of malignancies. Their etiology is mainly unknown. Here, we analyzed trends in incidence and occupational variation in risk of uterine leiomyosarcomas (LMS) and endometrial stromal sarcomas (ESS) in the Nordic countries aided by NORDCAN and NOCCA (Nordic Occupational Cancer) databases., Main Outcome Measures: Incidence rates per 100,000 and Standardized incidences rates (SIR) obtained from NORDCAN and NOCCA databases., Results: The incidence rates were about 0.3 per 100,000 for ESS and about 0.4 per 100,000 for LMS in Denmark, Finland, Iceland, and Norway. During the study-period (1978-2007), the incidence rates in each country were quite similar and constant. The age-specific incidence of LMS showed a peak around menopause. Significantly increased risk for LMS occurred in shoe and leather workers, farmers and teachers, whereas significantly low risk was detected with packers in the NOCCA data from Finland, Norway, and Sweden. For ESS no occupations showed either increased or decreased incidences., Conclusions: The incidence trends of LMS and ESS in our study were constant in four Nordic countries over time. The elevated risk for LMS with women exposed to leather work and animal dust indicates further exploration., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Previously published studies on the risk of cancer among male priests have been based on cancer mortality with the exception of one case-control study. The aim of this study was to present estimates of cancer incidence among Nordic male priests. The study cohort for our analyses consisted of 6.5 million men aged 30-64 years old who had participated in any computerised population census in four Nordic countries in 1990 or earlier. Follow-up was done by drawing linkages with the national population and cancer registries. 13,491 priests were identified by their job title codes. We estimated the standardised incidence ratio (SIR) and 95% confidence intervals (95% CI) for the priests using the male population as a reference. Priests had a lower cancer incidence than the general population (overall SIR 0.85, 95% CI: 0.82-0.88). The majority of smoking- and alcohol-related cancers were associated with decreased SIR estimates. Increased risks were observed for skin melanoma (SIR 1.34, 95% CI: 1.11-1.62), acute myeloid leukemia (SIR 1.75, 95% CI: 1.20-2.47) and thyroid cancer (SIR 1.86, 95% CI: 1.22-2.73). This is the first cohort study regarding the incidence of cancer among priests. The lower incidence of smoking and alcohol-related cancers among Nordic male priests can be explained by their lower exposure to cigarettes and alcohol when compared to the general population. A greater risk of melanoma is typical of highly-educated people, but it is unclear why priests should have an increased risk of acute myeloid leukemia or thyroid cancer.

Background: Women diagnosed with breast cancer at young age have been shown to be at higher risk of developing a new primary cancer than women diagnosed at older ages, but little is known about whether adjustment for calendar year of breast cancer diagnosis, length of follow-up, and/or breast cancer treatment alters the risk pattern by age., Methods: We identified 304,703 women diagnosed with breast cancer during 1943 to 2006 in the Cancer Registries of Denmark, Norway, and Finland. Relative risks (RR) of subsequent non-breast cancer by age at cancer diagnosis were calculated using Poisson regression models adjusted for country, calendar period, length of follow-up, and treatment. Excess absolute risks (EAR) were also calculated., Results: The RR for all cancer sites except breast cancer decreased with increasing age both with and without adjustments. The RR and the EAR differed for each age at diagnosis category until the women reached their late 70s. Many specific cancer forms contributed to the overall risk pattern by age with endometrial cancer as 1 exception., Conclusions: The age at breast cancer diagnosis is an essential risk factor for being diagnosed with a new primary non-breast cancer and the level of risk for specific ages at diagnosis may hold for many years after the diagnosis. Occurrence of endometrial cancer after breast cancer seems to follow a distinct age pattern different from that seen for most other cancer types., Impact: Future studies should aim at exploring the underlying explanations for the age-related findings., (©2011 AACR.)

Unlabelled: The NORDCAN database and program ( www.ancr.nu ) include detailed information and results on cancer incidence, mortality and prevalence in each of the Nordic countries over five decades and has lately been supplemented with predictions of cancer incidence and mortality; future extensions include the incorporation of cancer survival estimates., Material and Methods: The data originates from the national cancer registries and causes of death registries in Denmark, Finland, Iceland, Norway, Sweden, and Faroe Islands and is regularly updated. Presently 41 cancer entities are included in the common dataset, and conversions of the original national data according to international rules ensure comparability., Results: With 25 million inhabitants in the Nordic countries, 130 000 incident cancers are reported yearly, alongside nearly 60 000 cancer deaths, with almost a million persons living with a cancer diagnosis. This web-based application is available in English and in each of the five Nordic national languages. It includes comprehensive and easy-to-use descriptive epidemiology tools that provide tabulations and graphs, with further user-specified options available., Discussion: The NORDCAN database aims to provide comparable and timely data to serve the varying needs of policy makers, cancer societies, the public, and journalists, as well as the clinical and research community.

Trends in incidence and mortality rates of prostate cancer were analyzed using data from the national cancer registries of Denmark, Finland, Iceland, Norway, and Sweden. Joinpoint regression models were used to quantify temporal trends for the period from 1980 to 2004. Incidence rates were increasing and similar in the Nordic countries during the 1980s. Around 1990, a more rapid incidence increase began in all Nordic countries except Denmark, where an increase was seen 5 years later. In 2001, incidence rates in Denmark were half of those seen in the other Nordic countries, but mortality rates varied only marginally among countries. Mean annual declines in prostate cancer mortality of 1.9% (95% CI = 0.4% to 3.3%) and 1.8% (95% CI = 0.5% to 3.0%) were observed from 1996 to 2004 in Finland and Norway, respectively. During the same period, mortality rates leveled off in Iceland and Sweden but continued to increase in Denmark. The rapid increase in incidence during the early 1990s coincided with the introduction of the prostate-specific antigen (PSA) test and conveys little information about the occurrence of potentially lethal disease. Mortality rates, however, have recently stabilized or declined in countries where PSA testing and curative treatment have been commonly practiced since the late 1980s. Although other explanatory factors may be in operation, these trends are consistent with a moderate effect of increased curative treatment of early diagnosed prostate cancer and improved treatment of more advanced disease.

The Nordic countries have a long tradition of large-scale biobanking and comprehensive, population-based health data registries linkable on unique personal identifiers, enabling follow-up studies spanning many decades. Joint Nordic biobank-based studies provide unique opportunities for longitudinal molecular epidemiological research. The purpose of the present paper is to describe the possibilities for such joint studies, by describing some of the major Nordic biobank cohorts with a standardised calculation of the cancer incidence in these cohorts. Altogether two million donors have since 1966 donated more than four million biological samples, stored at -20 degrees C to -135 degrees C, to 17 biobank cohorts in Finland, Iceland, Norway and Sweden. As a result of joint database handling principles, the accuracy of personal identifiers and completeness of follow-up for vital status in all participating biobanks was improved. Thereafter, the cancer incidence was determined using follow-up through the national cancer registries. Biobanks based on random samples of population typically showed slightly lower cancer incidence rates than the general population, presumably due to better participation rates among health-conscious subjects. On the other hand, biobanks including samples for viral screening or clinical testing showed 1.5 to 2.1 fold increased incidence of cancer. This excess was very high immediately after sampling, but for some cancer sites remained elevated for years after clinical sampling. So far, more than 100 000 malignant neoplasms have occurred after sample donation, and the annual increase of the cancer cases in these cohorts is about 10 000. The estimates on the population-representativity of the biobanks will assist in interpretation of generalizability of results of future studies based on these samples, and the systematic tabulations of numbers of cancer cases will serve in study power estimations. The present paper summarizes optimal study designs of biobank-based studies of cancer.

All patients with total hip arthroplasty (THA) are exposed to soluble or particulate forms of Co and Cr. Adverse effects of these wear products are not known. Data from Nordic registries is used to estimate adverse effects on a large scale, based mostly on metal-on-polyethylene bearings. Cancer incidence was in line with the general population when the patients were operated on for all indications and significantly decreased when the indication was primary osteoarthritis. Stomach cancer and colorectal cancers were significantly reduced and prostate cancer and skin melanoma significantly increased. There was no significant excess of cancer in target organs, i.e. liver, kidney, or haematopoietic cancers. THA patients had reduced mortality and extended life expectancy compared with standard Nordic populations. All-site cancer incidence of the first-generation metal-on-metal McKee-Farrar patients operated on for primary osteoarthritis was in line with the general population after follow-up for up to 28 years. General mortality of these patients was also reduced and they also had an extended life expectancy. Temporary increases in haematopoietic cancers at different follow-up periods were seen in some cohorts. This malignancy deserves a special record linkage monitoring while large numbers of young patients are provided with the second generation of metal-on-metal prostheses.

This case-control study based in Nordic serum banks evaluated the joint effects of infections with genital human papillomavirus (HPV) types, and Chlamydia trachomatis in the aetiology of cervical squamous cell carcinoma. Through a linkage with the cancer registries, 144 cases were identified and 420 controls matched to them. Exposure to past infections was defined by the presence of specific IgG antibodies. The odds ratio (OR) for the second-order interaction of HPV16, HPV6/11 and C. trachomatis was small (1.0) compared to the expected multiplicative OR, 57, and the additive OR, 11. The interactions were not materially different among HPV16 DNA-positive squamous cell carcinomas. When HPV16 was replaced with HPV18/33 in the analysis of second-order interactions with HPV6/11 and C. trachomatis, there was no evidence of interaction, the joint effect being close to the expected additive OR. Possible explanations for the observed antagonism include misclassification, selection bias or a true biological phenomenon with HPV6/11 and C. trachomatis exposures antagonizing the carcinogenic effects of HPV16.

Objective: Infection with oncogenic human papillomaviruses (HPVs) is the most important cause of cervical cancer worldwide. After infection there is a long latency period of at least 10 to 15 years during which cervical cancer develops in a small proportion of originally infected women. Up to 50% of these women have at diagnosis antibodies to the HPV oncoproteins E6 and E7, which are rarely found among healthy women. Our purpose was to evaluate whether antibodies to HPV16 and HPV18 E6 and E7 proteins are useful for early diagnosis of cervical cancer by measuring the antibody response in women in whom cervical cancer later developed., Study Design: A joint serum bank of 550,000 Swedish, Norwegian, and Finnish women was followed up for 0.5 to 20 years, after which 178 invasive cervical carcinoma (ICC) cases, 150 of whom had squamous cell carcinoma (SCC), and 527 controls were identified. Antibodies to HPV16 and HPV18 E6 and E7 proteins were determined by tag enzyme-linked immunoassays., Results: HPV16/18 E6 and E7 antibodies were detected infrequently (7.0%) in women in whom SCC later developed and yielded a moderately increased estimate of associated relative risk (odds ratio 2.7, 95% CI 1.1-6.4). Sensitivity of the combined antibody tests for the detection of occult SCC varied between 6% and 14% but was not related to time lag between serum sampling and cancer diagnosis., Conclusion: HPV16/18 E6 and E7 antibody responses are not sensitive markers of occult cervical cancer.

Cervical carcinoma is a sexually transmitted disease most strongly linked with human-papillomavirus (HPV) infection. We conducted a prospective sero-epidemiologic study to evaluate the role of Chlamydia trachomatis infection in the development of cervical carcinoma, with invasive cancer as an end point. A nested case-control study within a cohort of 530000 Nordic women was performed. Linking data files of 3 Nordic serum banks and the cancer registries of Finland, Norway and Sweden identified 182 women with invasive cervical carcinoma diagnosed during a mean follow-up of 5 years after serum sampling. The serum samples of the cases and matched cancer-free controls were analyzed for IgG antibodies to C. trachomatis, C. pneumoniae (a control microbe) and HPV types 16, 18 and 33, as well as for serum cotinine (an indicator of tobacco smoking). Serum antibodies to C. trachomatis were associated with an increased risk for cervical squamous-cell carcinoma (HPV- and smoking-adjusted OR, 2.2; 95% CI, 1.3-3.5). The association remained also after adjustment for smoking both in HPV16-seronegative and -seropositive cases (OR, 3.0; 95% CI, 1.8-5.1; OR, 2.3, 95% CI, 0. 8-7.0 respectively). No such association was found for C. pneumoniae. Our prospective study provides sero-epidemiologic evidence that infection with C. trachomatis confers an increased risk for subsequent development of invasive squamous-cell carcinoma of the uterine cervix., (Copyright 2000 Wiley-Liss, Inc.)

Human papillomavirus (HPV) types 16 and 18 are the major risk factors for cervical carcinoma, whereas HPV types 6 and 11 cause benign genital lesions. We wanted to study the joint effect of simultaneous infections with the oncogenic and non-oncogenic HPV types on risk of subsequent development of cervical carcinoma. A cohort of 530,000 women who had donated blood samples to Nordic serum banks between 1973 and 1994 was followed up by linkage to national cancer registries. We identified 182 prospective cases with invasive cervical carcinoma and selected 538 matched controls at random. HPV 6, 11, 16, 18 and 33 seropositivity was used as a marker for the different HPV infections, and seropositivity for Chlamydia trachomatis and cotinine were used as markers for risk-taking sexual behavior and smoking respectively. The adjusted odds ratio (OR) of cervical squamous-cell carcinoma (SCC) was 2.2 for HPV6/11 among HPV16 seronegatives and 5.5 for HPV16 among HPV6/11 seronegatives. Assuming multiplicative joint effect, the expected OR for seropositivity to both HPV6/11 and HPV16 would have been 12, but the observed OR was 1.0. The antagonistic interaction was statistically significant (p = 0.001) and present also under deterministic considerations of possible misclassification bias. Antagonistic interactions were also detected for combinations of HPV16 and HPV18 and of HPV16 and HPV33. The results are in line with the concept that HPV-specific immunity protects against SCC and support primary prevention of SCC by vaccination against the HPVs.

Objective: To evaluate the association between infection with the major oncogenic types of human papillomavirus and the risk of developing non-cervical anogenital cancers in a cohort followed up prospectively., Design: Data from two large serum banks to which about 700,000 people had donated serum samples were followed up for a mean of 8 years. People who developed non-cervical anogenital cancers during follow up were identified by registry linkage with the nationwide cancer registries in Finland and Norway. Within this cohort a nested case-control study was conducted based on the serological diagnosis of infection with human papillomavirus types 16, 18, and 33., Subjects: 81 cases and 240 controls matched for sex, age, and storage time of serum samples., Main Outcome Measures: Odds ratios of developing non-cervical anogenital cancers in presence of IgG antibodies to specific micro-organisms., Results: Subjects seropositive for human papillomavirus type 16 had an increased risk of developing non-cervical anogenital cancers (odds ratio 3.1 (95% confidence interval 1.4 to 6.9)). Subjects seropositive for type 33 also had an increased risk (odds ratio 2.8 (1.0 to 8.3)) but not significantly after adjustment for infection with type 16. Seropositivity for human papillomavirus type 16 was associated with an increased risk of developing vulvar and vaginal cancers (odds ratio 4.5 (1.1 to 22)) and a strongly increased risk of developing preinvasive vulvar and vaginal lesions (odds ratio infinity (3.8 to infinity)). Seropositivity for human papillomavirus type 18 increased the risk of developing preinvasive lesions (odds ratio 12 (1.2 to 590)). High, but non-significant odds ratios for types 16 and 33 were seen for penile cancers., Conclusions: This study provides prospective seroepidemiological evidence that infection with human papillomavirus type 16 confers an increased risk of developing non-cervical genital cancers, particularly vulvar and vaginal cancers.

An overview is given of the most important known causes of cancer in the five Nordic countries and the resulting number of cancers that are potentially avoidable. The main causes include active and passive smoking, alcohol consumption, exposure to asbestos and other occupational carcinogens, solar and ionizing radiation, obesity, human papillomavirus infection in the female genital tract and infection with Helicobacter pylori. The organs most commonly affected are those of the respiratory system, the upper digestive tract and stomach, skin, the lower urinary tract and the uterine cervix. Annually, more than 18,000 cancers in men and 11,000 in women in the Nordic populations could be avoided by eliminating exposure to known carcinogens which is equivalent to 33% and 20% of all cancers arising in men and women, respectively, around the year 2000. Smoking habits account for a little more than half of these avoidable cases. Estimates of avoidable cancers are given for each Nordic country, separately.