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Background: Opium use has been associated with an increased risk of cancers of the lung, oesophagus, and pancreas, and it was recently classified by the International Agency for Cancer Research as carcinogenic to humans. It is not clear whether opium also increases the risk of colorectal cancer (CRC). The aim of our study was to assess the association between various metrics of opium use and the risk of CRC., Methods: This case-referent study from seven provinces in Iran comprised 848 CRC cases and 3215 referents. Data on opium use (duration, amount, frequency) and potential confounders were collected by trained interviewers. Multivariable unconditional logistic regression models were used to measure odds ratios (OR) adjusted for age, gender, province, marital status, family history of CRC-linked cancers, consumption of red meat, fruits and vegetables, body shape, occupational physical activity, and socioeconomic status., Results: Regular opium consumption was not associated with the risk of CRC (OR 0.9, 95% confidence interval, CI: 0.7, 1.2) compared to subjects who never used opium. However, frequent opium use more than twice a day was associated with an increased risk of CRC compared to non-users of opium (OR: 2.0, 95% CI: 1.1, 3.8; p for quadratic trend 0.008)., Conclusion: There seems to be no overall association between opium use and CRC, but the risk of CRC might be increased among persons who use opium many times a day.

Introduction: Professional visual artists constitute a heterogeneous vocational group, including, but not limited to painters, photographers, textile artists, and sculptors who may face exposure to workplace hazardous substances and lifestyle factors that may contribute to the development of selected cancers. The objective of this registry-based cohort study was to assess the cancer incidence among Nordic visual artists., Materials and Methods: This study is based on data from the Nordic Occupational Cancer (NOCCA) project that combines census data of 15 million people from all Nordic countries and cancer registries from 1961 to 2005. For the present study we selected a cohort of visual artists from Finland, Iceland, Norway, and Sweden. Standardized incidence ratio (SIR) analyses were conducted with the cancer incidence rates for the entire national study populations used as reference rates., Results: In male visual artists, there were statistically significant excesses in cancers of the tongue (SIR 2.91, 95% confidence interval 1.74-4.55), oral cavity (2.09, 1.26-3.27), pharynx (2.18, 1.45--3.15), testis (1.91, 1.11-3.05), renal pelvis (2.48, 1.42-4.03) and bladder (1.33, 1.14-1.55). The risk was significantly decreased for cancers of the lip (0.45, 0.18-0.93) and stomach (0.65, 0.50-0.84). In female visual artists, the only significantly increased risk was observed for breast cancer (1.29, 1.13-1.48) and the only significantly decreased risk for stomach cancer (0.43, 0.17-0.88). The incidence of lung cancer was close to the population average in both sexes., Conclusions: The non-elevated incidence of lung cancer suggests a similar prevalence of smoking between visual artists and the general population, while the elevated risk of cancers of mouth and pharynx among male visual artists is suggestive of more widespread alcohol drinking. The excess risk of urogenital cancers might be associated with exposure to solvents.

Introduction: While certain occupations, such as agriculture and fishery, have been associated with an increased risk of lip cancer, the occupational risk profile of lip cancer and its change over time remain poorly known. This study aims to evaluate the incidence of lip cancer across different occupations in the Nordic countries., Methods: The Nordic Occupational Cancer Study (NOCCA) covers 14.9 million people and includes 45 years of cancer incidence data, from 1961 to 2005, linked to occupational categories for all the five Nordic populations. Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were used to quantify the risk of lip cancer across occupational categories relative to the entire national populations., Results: There were a total of 14,477 male and 3008 female lip cancer patients identified during follow up. The highest SIRs were observed among male fishermen (SIR 2.26, 95% CI: 2.04-2.50), gardeners (SIR 1.60, 95% CI: 1.48-1.72), and farmers (SIR 1.60, 95% CI: 1.55-1.66). A significantly reduced risk of lip cancer (SIR < 0.50) was observed among male physicians, teachers, religious workers, artistic workers, journalists, administrators, printers, waiters, and hairdressers. Among women, no occupations were associated with an increased risk of lip cancer., Conclusions: The incidence of lip cancer varies widely between outdoor and indoor occupations. Occupations involving outdoor activity and exposure to sunlight show the most elevated SIRs.

Background: Parity is known to have a protective effect as regards ovarian cancer, but its effect on the different histological subtypes of ovarian cancer is not well known. The impact of parity on the incidence of ovarian cancer subtypes was studied., Material and Methods: All Finnish women diagnosed 1994-2013 with ovarian cancer for the first time were included. Altogether, 5412 cases of ovarian cancer were identified in the Finnish Cancer Registry and stratified according to morphology into serous, mucinous, endometrioid, clear cell and others. Five age-matched controls were randomly selected for each case from the Finnish National Population Registry. Data on postmenopausal hormonal therapy were derived from the Registry of Prescribed drugs and used as cofactors. Multivariate conditional logistic regression for matched case-control data was used to examine the associations between parity parameters and ovarian cancer risk., Results: Parous women had lower risk than nulliparous women in getting ovarian cancer of any type under age of 55 years. The odds ratio (OR) for serous cancer was 0.65 (95% confidence interval 0.56-0.77), for mucinous cancer 0.66 (0.52-0.83), for endometrioid cancer 0.52 (0.40-0.68), for clear-cell cancer 0.30 (0.19-0.46) and for other types 0.59 (0.43-0.80). In women aged 55 or older, the respective ORs were 0.86 (0.75-0.99), 0.78 (0.57-1.07), 0.61 (0.47-0.79), 0.44 (0.29-0.66) and 0.74 (0.57-0.95), adjusted for hormone therapy. Number of childbirths was associated with a trend toward reduction of risk, especially in serous and clear-cell cancers. Higher age at first birth was associated with higher risk of clear-cell cancer but otherwise age at first or last birth did not have an impact on the incidence of cancer subtypes., Conclusions: Childbirths decrease the risk of all histologic subtypes of epithelial ovarian cancer in women in premenopausal and postmenopausal age.

Background: There are studies suggesting that participation in musical activities may protect from cancer. On the other hand, some musicians have a lifestyle that might increase the risk of cancer. The objective of this study was to assess the cancer pattern of musicians in four Nordic countries., Material and Methods: This study combines census and cancer registry data from 1961 to 2005 for 13 million people from Finland, Iceland, Norway, and Sweden. Standardized incidence ratio (SIR) analyses were conducted with the cancer incidence rates for entire national populations used as reference rates., Results: There were 11,401 male and 3105 female musicians with 2039 cancer cases. The SIR for all sites combined was 1.02 (95% confidence interval 0.97-1.07) in men and 1.04 (0.94-1.15) in women. In male musicians, there were statistically significant excesses in oropharyngeal cancer (4.36, 2.73-6.60), esophageal cancer (2.08, 1.51-2.81), liver cancer (1.81, 1.26-2.52), and skin melanoma (1.40, 1.10-1.75). The risk was decreased in lip cancer (0.13, 0.02-0.48), stomach cancer (0.66, 0.50-0.82), and lung cancer (0.77, 0.65-0.90). In female musicians, there were no statistically significant SIRs in any of the cancer types studied, but the risk of breast cancer was significantly elevated in the age category of 70+ (1.52, 1.04-2.15). The overall SIR was stable over the 45 year period of observation, but strong decreases were observed in the SIRs of esophageal cancer, liver cancer, laryngeal cancer, and skin melanoma., Conclusion: Musicians have characteristics of indoor workers such as low incidence of lip cancer and high incidence of skin melanoma. The low incidence of lung cancer suggests that the prevalence of smoking among musicians is lower than in the general population while the elevated risk of alcohol-related cancer types suggest that drinking is likely more common among musicians. The cancer risk for all sites combined is still similar to that of the general population in the four countries studied.

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: There are only a few and mostly small population-based epidemiological studies of primary sclerosing cholangitis (PSC). Objective: We aimed to estimate prevalence and incidence rates of PSC, and survival and malignancy risk for PSC patients in a large population-based study. Methods: We retrieved 632 PSC patients from 1990 to 2015 in the Hospital District of Helsinki and Uusimaa (HUS), comprising 29% of the Finnish population. Mortality information of the PSC patients was obtained from the national Population Registry, malignancy information from the Finnish Cancer Registry and the causes of death from the Statistics Finland. Standardized incidence ratio and standardized mortality ratio (SMR) were calculated for predefined malignancy types. Results: The crude incidence of PSC in the HUS area was 1.58/100,000 person-years, and the point prevalence in 2015 was 31.7/100,000 inhabitants. The mean time from diagnosis to death was 21.9 years. The risk for any malignancy was three-fold and the risk for colorectal carcinoma was five-fold when comparing with the general population. During the first year after diagnosis of PSC, the risk for cholangiocarcinoma is 900-fold compared to the general population and after that 150-fold. SMR for all malignant neoplasms was 5.9 (95% CI 4.2-8.1). Conclusion: We found that the incidence of PSC in the HUS area in Finland is similar or higher than previously reported from other countries. The prevalence is markedly higher than reported elsewhere, probably due to the active search of the disease, suggesting that the disease is underdiagnosed.

Background: Cancer is currently one of the most important factors affecting the long-term health and survival of heart transplant patients. Material and methods: We calculated the standardized incidence ratios (SIR) for different cancer sites and the cancer-specific standardized mortality ratio (SMR) by linking a cohort of 479 adult heart transplant recipients transplanted in 1985-2014 (4491.6 person-years of follow-up) with data from the national Finnish Cancer Registry until the end of 2015, and with the data from the Statistics Finland's national registry of causes of death. Results: A total of 267 cancers occurred in 143 patients (SIR 6.0; 95% confidence interval (CI) 5.3-6.7). The SIR for overall cancer was considerably higher for men (SIR 6.7; 95% CI 5.9-7.5) than for women (1.4; 95% CI 0.6-2.6). Most frequent cancers were non-melanoma skin cancers (basal cell carcinoma 83 cases, squamous cell skin cancer (SCC) 56 cases), followed by Non-Hodgkin lymphoma (NHL) (36 cases), lung cancer (17), cancer of prostate (16) and cancer of kidney (12). SIRs were highest for SCC (51.9; 95% CI 39.2-67.4), lip cancer (47.4; 95% CI 19.1-97.7), cancer of tongue (26.3; 95% CI 7.2-67.4), and NHL (25.7; 95% CI 18.0-35.6). For most cancers, SIRs increased steadily by time since transplantation. Cancer mortality was three times higher for heart transplant recipients than for the population (SMR 3.1; 95% CI 2.1-4.1). Conclusions: Both cancer incidence and mortality are remarkably increased after heart transplantation, with the relative incidence most elevated for SCC, lip and other oral cancers, and for NHL.

Background: Placentation is characterized by extensive cell proliferation and neovascularization, which is similar to the processes observed in the development of cancer. Nonetheless, little is known about the relation between abnormal placentation, such as placental abruption, and cancer., Material and Methods: Data on women with placental abruption in a singleton pregnancy between 1971 and 2005 (n = 7804) were collected from the Finnish Hospital Discharge Registry and the Finnish Medical Birth Registry. The cohort was then linked with the Finnish Cancer Registry records until the end of 2013. Standardized incidence ratios (SIRs) were calculated for different cancers by dividing the observed numbers of cancers by those expected. The expected numbers were based on national cancer incidence rates., Results: During follow-up, 597 cancers were found among women with a history of placental abruption. The overall risk of cancer was not increased (SIR 0.95, 95% CI 0.88-1.02). However, the history of placental abruption was associated with an increased risk of lung cancer (SIR 1.51, 95% CI 1.05-2.10) and thyroid cancer (SIR 1.47, 95% CI 1.04-2.02). A decreased risk was found for breast cancer (SIR 0.85, 95% CI 0.75-0.96). The risk of rectal cancer was also decreased, although these numbers were small (SIR 0.49, 95% CI 0.20-1.01)., Conclusions: Overall, the risk of lung cancer was increased, and the risk of breast cancer decreased, in women with a history of placental abruption. These observations can be explained to some extent by risk factors or risk markers for placental abruption. The increased risk of thyroid cancer may be explained by surveillance bias.

Background: Occupational exposure has been identified as the most important risk factor for bladder cancer second to smoking. The objective of this study was to estimate the occupational variation in risk of bladder cancer that is not attributable to smoking., Material and Methods: In the Nordic Occupational Cancer study (NOCCA), 111,458 cases of bladder cancer and 208,297 cases of lung cancer cases were observed among men in Denmark, Finland, Iceland, Norway and Sweden during 1961-2005. Relative smoking prevalence in an occupation was estimated based on standardized incidence ratio (SIR) for lung cancer in the given occupation. Crude and smoking-adjusted SIRs with 95% confidence intervals (CI) for bladder cancer were calculated for each occupation., Results: The smoking-adjusted SIR for most of the occupations was closer to 1.00 than the unadjusted SIR. The highest statistically significant smoking-adjusted SIRs were observed among chimney sweeps (SIR 1.29, 95% CI 1.05-1.56), waiters (1.22, 1.07-1.38) hairdressers (1.14, 1.02-1.26), cooks and stewards (1.12, 1.01-1.25), printers (1.11, 1.04-1.18) and seamen (1.09, 1.03-1.14)., Conclusions: Smoking is a strong risk factor for bladder cancer but there may also be other factors in some specific occupations in addition to smoking. The occupational variation in risk of bladder cancer is small when adjusted for smoking, but risk increasing factors are indicated in some occupations.

Objective: The aim of this study was to assess the cancer risk in a cohort of Finnish patients with systemic lupus erythematosus (SLE) when followed over the long term., Method: The cohort consisted of 182 female and 23 male SLE patients treated at the Helsinki University Central Hospital from 1967 to 1987. The cohort was linked to the Finnish Cancer Registry and followed for cancer incidence from 1967 to 2013. Standardized incidence ratios (SIRs) were calculated by dividing the number of observed cases by the number of expected cases for different types of cancer., Results: The mean duration of follow-up was 25.7 years. Forty-five patients out of 205 were diagnosed with cancer, with an increased risk of overall malignancy [SIR 1.90, 95% confidence interval (CI) 1.39-2.54, p < 0.001]. The incidences of soft-tissue sarcoma (SIR 12.1, 95% CI 1.47-43.7, p < 0.05), non-Hodgkin's lymphoma (SIR 12.1, 95% CI 5.82-22.3, p < 0.001), and kidney cancer (SIR 7.79, 95% CI 2.53-18.2, p < 0.01) were significantly elevated., Conclusion: This long-term study confirms that patients with SLE have an increased risk of cancer, particularly non-Hodgkin's lymphoma and kidney cancer.

Background: While the link between mental illness and cancer survival is well established, few studies have focused on colorectal cancer. We examined outcomes of colorectal cancer among persons with a history of severe mental illness (SMI)., Material and Methods: We identified patients with their first colorectal cancer diagnosis in 1990-2013 (n = 41,708) from the Finnish Cancer Registry, hospital admissions due to SMI preceding cancer diagnosis (n = 2382) from the Hospital Discharge Register and deaths from the Causes of Death statistics. Cox regression models were used to study the impact on SMI to mortality differences., Results: We found excess colorectal cancer mortality among persons with a history of psychosis and with substance use disorder. When controlling for age, comorbidity, stage at presentation and treatment, excess mortality risk among men with a history of psychosis was 1.72 (1.46-2.04) and women 1.37 (1.20-1.57). Among men with substance use disorder, the excess risk was 1.22 (1.09-1.37)., Conclusion: Understanding factors contributing to excess mortality among persons with a history of psychosis or substance use requires more detailed clinical studies and studies of care processes among these vulnerable patient groups. Collaboration between patients, mental health care and oncological teams is needed to improve outcomes of care.

Background: The Nordic Cancer Registries are among the oldest population-based registries in the world, with more than 60 years of complete coverage of what is now a combined population of 26 million. However, despite being the source of a substantial number of studies, there is no published paper comparing the different registries. Therefore, we did a systematic review to identify similarities and dissimilarities of the Nordic Cancer Registries, which could possibly explain some of the differences in cancer incidence rates across these countries., Methods: We describe and compare here the core characteristics of each of the Nordic Cancer Registries: (i) data sources; (ii) registered disease entities and deviations from IARC multiple cancer coding rules; (iii) variables and related coding systems. Major changes over time are described and discussed., Results: All Nordic Cancer Registries represent a high quality standard in terms of completeness and accuracy of the registered data., Conclusions: Even though the information in the Nordic Cancer Registries in general can be considered more similar than any other collection of data from five different countries, there are numerous differences in registration routines, classification systems and inclusion of some tumors. These differences are important to be aware of when comparing time trends in the Nordic countries.

Background: Objective was to quantify biases in screening for gastric cancer when comparing attenders to nonattenders using serum pepsinogen I (SPGI) level as primary test., Methods: In mid 1990s, all men aged 51-65 years from two Finnish cities were invited to SPGI screening. Mortality and premature mortality in attenders were compared to nonattenders. Efficacy of screening was studied by 15 years' follow-up of standardized mortality ratio (SMR) and potential years of life lost (PYLL) due to gastric cancer. Bias due to selective attendance was quantified using corrective coefficients based on total cancer incidence and mortality, and gastric cancer-specific incidence and mortality for total population and nonattenders., Results: In 1994-1996, men aged 51-65 years (16,872) were invited to SPGI assay and 12,175 men (72%) attended. SPGI was 25 microg/l or less in 610 (5%) men, indicating severe atrophic gastritis (AG). Post-screening gastroscopy was performed to 435 men with low SPGI. Of these, 168 men were referred for treatment due to abnormal focal lesions. Attributable proportions in reductions of SMR and PYLL from gastric cancer due to screening were 59% and 67%. After correcting for selective participation, attributable proportions were reduced to 23% and 39%., Conclusions: Biomarker screening by low SPGI among middle-aged men followed by upper gastrointestinal endoscopy decreased long-term and premature mortality due to gastric cancer. However, in spite of methodological corrections done, the results do not justify any firm conclusions or recommend general screening programs. Randomized trials are warranted for this purpose.

Background: Levonorgestrel-releasing intrauterine system (LNG-IUS) is used for contraception and heavy menstrual bleeding. A long-term hormone therapy can modify the risk of gynecologic cancers. Little is known about the impact of LNG-IUS use on the risk for invasive and borderline ovarian tumor subtypes or for primary fallopian tube carcinoma. We examined the associations of LNG-IUS use with these tumors., Material and Methods: We identified from the national Medical Reimbursement Registry of Finland the women aged 30-49 years who had used LNG-IUS for menorrhagia in 1994-2007, and from the Finnish Cancer Registry ovarian cancers and primary fallopian tube carcinomas diagnosed before the age of 55 and by the end of 2013., Results: A total of 77 invasive ovarian cancers and seven primary fallopian tube carcinoma cases were diagnosed in a cohort of 93 843 LNG-IUS users during the follow-up of 1 083 126 women-years. The LNG-IUS users had decreased risk for both invasive ovarian cancer [standardized incidence ratio (SIR) 0.59, 95% confidence interval (CI) 0.47-0.73] and for borderline ovarian tumors (SIR 0.76, 95% CI 0.57-0.99) as compared to the background population. The risk of primary fallopian tube carcinoma was not increased (SIR 1.22, 95% CI 0.49-2.50). Decreased risks for mucinous (SIR 0.49, 95% CI 0.24-0.87), endometrioid (SIR 0.55, 95% CI 0.28-0.98), and serous ovarian carcinomas (SIR 0.75, 95% CI 0.55-0.99) were seen in LNG-IUS users., Conclusions: LNG-IUS use associated with decreased risk for both invasive and borderline ovarian tumors. The incidence of primary fallopian tube carcinoma did not significantly differ between LNG-IUS users and the background population.

Objective: We investigated the risk of gastric cancer among men with Helicobacter pylori (H. pylori) infection or atrophic gastritis (AG) in a 15-year follow-up., Materials and Methods: Study population consists of 12,016 men aged 50-65 years at the beginning of the follow-up in 1994-1996. Serum levels of pepsinogen I (SPGI) and antibodies (IgG) to H. pylori (HpAb) were assayed from serums collected in 1994-1996. Incidence of gastric cancer in the study population was assessed in follow-up from 1994 to 2011 by data from the nationwide cancer registry. Based on SPGI and HpAb values, standardized incidence ratios (SIRs) of gastric cancer were calculated in three subgroups, that is, in those with a healthy stomach, those with H. pylori infection but without AG and those with AG. Risk ratios (RR) of gastric cancer were calculated using SIR of subgroups., Results: During 15 years, seven gastric cancers appeared per 79,928 person years among men with healthy stomachs, 50 cancers per 92,533 person years in men with H. pylori infection but without AG, and 8 per 8658 person years in men with AG. Risk ratio (RR) of stomach cancer in men with H. pylori infection was 5.8 (95%CI: 2.7-15.3) compared to men with healthy stomachs, and 9.1 (95%CI: 2.9-30.0) in men with AG. There were no differences in cancer risk between cardia and distal stomach., Conclusions: Risk of gastric cancer is low in men with healthy stomachs. It is significantly increased in those with H. pylori infection and more in those with AG.

Objective: We studied the incidence of severe ALD requiring hospitalization in Finland, and survival and causes of death among the ALD patients., Methods: A cohort of 11,873 persons (8796 men and 3077 women) with diagnosis of ALD during the years 1996-2012 was identified from Finnish national Inpatient Register. The annual incidence of alcoholic hepatitis (AH) and alcoholic liver cirrhosis was calculated. The cohort was combined with the data from national Cause of Death Register of Statistics Finland., Results: The incidence of alcoholic liver cirrhosis increased from 8.8/100,000 in year 2001 to 14.6/100,000 in year 2012 among men and from 2.4 to 4.2/100,000 among women. The incidence of AH increased from 3.7 to 6.5/100,000 among men and from 1.3 to 2.7/100,000 among women. The relative 5-year survival ratios of patients with alcoholic liver cirrhosis and AH were 29 and 50% among men and 38 and 52% among women, respectively. Out of 8440 deaths, 65% were due to alcoholic-related causes. The risk of death among ALD patients was increased in malignancies (SMR 6.82; 95% CI: 6.35-7.29), cardiovascular diseases (6.13; 5.74-6.52), respiratory diseases (7.86; 6.70-9.10), dementia (3.31; 2.41-4.44) and accidents and violence (11.12; 10.13-12.15)., Conclusions: The incidence of AH and alcoholic liver cirrhosis is increasing. The survival is poor. Most deaths are alcohol-related and other common causes of excess deaths are cancers especially in the upper aerodigestive tract and cardiovascular, digestive and respiratory diseases as well as violence and accidents.

Background: For an effective colorectal cancer (CRC) screening program, high participation rate is essential. However, non-participation in CRC screening program has increased in Finland., Material and Methods: The study was based on a population-based nationwide cohort of persons invited for CRC screening in 2004-2011. Information on the first round of the CRC screening participation and related background factors was obtained from the Finnish Cancer Registry, and information about health behavior factors from the Health Behavior Survey (HBS) in 1978-1999. Non-participation in CRC screening was analyzed with Poisson regression as incidence rate ratios (IRR) with 95% confidence intervals (95% CI)., Results: Of all persons invited for CRC screening (79 871 men and 80 891 women) 35% of men and 21% of women refused. Of those invited for screening, 2456 men (3.1%) and 2507 women (3.1%) were also invited to the HBS. Persons, who declined HBS, were also more likely to refuse CRC screening (men IRR 1.40, 95% CI 1.26-1.56, women 1.75, 1.52-2.02) compared to HBS participants. Never married persons had about a 75% higher risk for refusing than married ones. The youngest age group (60 years) was more likely to refuse screening than the older age groups (62 or >64 years). Smoking was associated with non-participation in screening (current smokers, men: IRR 1.32, 95% CI 1.05-1.67, women: 2.10, 1.61-2.73)., Conclusions: Participation in CRC screening was affected by gender, age, and marital status. Persons, who refused the HBS, were also more likely to refuse CRC screening. Smoking was a risk factor for non-participation in CRC screening.

Background: In epidemiological studies, Hodgkin lymphomas (HL) in children younger than 15 years and HL in adolescents and younger adults age 15-35 years has traditionally been studied separately, under the assumption that HL at age 0-14 constitute a homogeneous entity. However, the continued validity of this research practice in affluent settings may be questioned. Specifically, the boundary at age 15 years may not be epidemiologically justified, and therefore also questionable clinically. We therefore updated and further characterised recent HL incidence patterns among Nordic children., Material and Methods: We obtained HL incidence data in children aged 0-14 years for the period 1978-2010 from the five nationwide Nordic cancer registries. The data were analysed by log-linear and/or a mixture of Poisson regression models., Results: The analyses showed statistically significantly decreasing and increasing HL incidence rates in children younger and older than eight years, respectively during the study period. Statistical modelling suggested that cases in children age 0-6 years constituted a disease entity of its own, whereas cases in older children were more likely to belong to the younger adult HL entity., Conclusion: Diverging incidence trends and statistical modelling suggest that HL in children age 0-14 years cannot be assumed to constitute a homogeneous disease entity in affluent settings.

Background: Prolonged steroid hormone therapy increases the risk of breast cancer, especially the risk of lobular cancer, but the effect of the levonorgestrel-releasing intrauterine system (LNG-IUS) use is controversial. In this study we aimed to test the hypothesis that risk for lobular breast cancer is elevated among LNG-IUS users., Material and Methods: We identified from the national Medical Reimbursement Registry of Finland the women aged 30-49 who had used LNG-IUS for the treatment or prevention of menorrhagia in 1994-2007, and from the Finnish Cancer Registry breast cancers diagnosed before the age of 55 and by the end of 2012., Results: A total of 2015 women had breast cancer diagnosed in a cohort of 93 843 LNG-IUS users during follow-up consisting of 1 032 767 women-years. The LNG-IUS users had an increased risk for both ductal breast cancer [standardized incidence ratio (SIR) 1.20, 95% confidence interval (CI) 1.14-1.25] and for lobular breast cancer (SIR 1.33, 95% CI 1.20-1.46), as compared with the general female population. The highest risk was found in LNG-IUS users who purchased the device at least twice, whose SIR for lobular cancer was 1.73 (95% CI 1.37-2.15)., Conclusions: The results imply that intrauterine administration of levonorgestrel is not only related to an excess risk of lobular breast cancer but also, in contrary to previous assumptions, to an excess risk of ductal breast cancer.

Background: Many studies have previously revealed evidence of an association between grand multiparity (five or more deliveries) and gynaecological cancer. Oestrogen has an impact on cancer formation and the amount of circulating oestrogen is significantly higher during pregnancy. Also the lifestyle of grand multiparous women differs somewhat from the average population. Considering these factors it is plausible that also non-gynaecological cancers are associated with multiparity. The aim of our study was to determine cancer incidence among grand multiparous women, with special attention to non-gynaecological cancers., Material and Methods: All 102 541 women alive in 1974-2011 and having had at least five deliveries were identified in the Finnish Population Register and followed up for cancer incidence through the Finnish Cancer Registry to the end of 2011. Standardised incidence ratios (SIRs) were defined as ratios between observed and expected numbers of cases, the latter ones based on incidence in the entire Finnish female population., Results: The overall incidence of non-gynaecological cancers was the same as in the reference population (SIR 0.98, 95% confidence interval 0.90-1.06). The incidence of cancers of the gall-bladder (SIR 1.42, 1.26-1.58), biliary tract (1.19, 1.04-1.35) and kidney (1.22, 1.14-1.31) was increased. There were significantly fewer cases than expected of urinary bladder cancer (SIR 0.70, 0.61-0.78), lung cancer (0.87, 0.81-0.92), colon cancer (0.94, 0.89-0.99) and all types of skin cancers. As a consequence of the decreased incidence of gynaecological cancers (SIR 0.74, 0.71-0.77) and breast cancer (0.60, 0.58-0.61), the SIR for cancer overall was 0.84 (0.83-0.85)., Conclusion: The study demonstrated that grand multiparous women have a similar overall risk of non-gynaecological cancers as other women, despite significant differences in some specific forms of cancer.

OBJECTIVE. Patients with inflammatory bowel disease (IBD) are at increased risk of certain cancers. We assessed the long-term risks of malignancies among patients with IBD in Finland. METHODS. A total of 21,964 patients with IBD (16,649 with UC and 5315 with CD) from the database of the Social Insurance Institution were diagnosed in the periods 1987-1993 and 2000-2007 and followed up to the end of 2010 in a linkage with the nationwide Finnish Cancer Registry. The numbers of cancers observed were compared to those expected in general population and expressed as a standardized incidence ratio (SIR). RESULTS. Overall, male patients with CD and UC had a slightly increased risk of malignancies. Patients with UC were found to have an increased risk of colon (SIR 1.81, 95% confidence interval 1.46-2.21), rectal (1.76, 1.35-2.25), biliary tract (7.26, 4.37-11.1), and thyroid cancers (1.93, 1.28-2.79). The risk of colorectal cancer (CRC) was highest among the youngest UC patients. Patients with CD had a significantly increased SIR for cancers of the small intestine (9.97, 4.30-19.6), anus (9.51, 1.96-27.8), and biliary tract (4.93, 1.02-14.4), and also for myeloma (2.84, 1.14-5.85). In addition, the risk of basal cell skin cancer was increased in IBD (1.29, 1.16-1.43). Males with UC had a slightly decreased risk of lung and prostate cancers. CONCLUSIONS. The incidence of cancer among male patients with CD and CU was higher than that in general population. Patients with UC are at increased risk for CRC and biliary tract cancers. CRC risk was highest in the youngest patients.

Objective: While previous data link the use of postmenopausal hormone therapy to an increased risk for ovarian cancer, little is known about the impact of various progestins, modes or routes of administration of hormone therapy for this risk. In this nationwide study, we compared relations between different estradiol-progestin (EPT) formulations and epithelial ovarian cancer risk., Methods: All Finnish women over 50 years using EPT for at least 6 months (224 015 women with 602 ovarian cancers) during 1994-2006 were identified from the reimbursement register. The incidence of ovarian cancer in EPT users was compared to that in the age-matched background population by means of observed to expected ratio (standardized incidence ratio, SIR)., Results: Ovarian cancer risk was not elevated for EPT use of < 5 years but it was elevated for EPT use of ≥5 years (SIR 1.21, 95% confidence interval (CI) 1.06-1.37). Medroxyprogesterone acetate and norethisterone acetate as components of EPT were associated with similar risks for use for ≥ 5 years (SIR 1.26, 95% CI 0.94-1.64 and SIR 1.42, 95% CI 1.11-1.77, respectively). The risk did not differ between sequential or continuous EPT regimens or between oral or transdermal EPT formulations. The risk elevation for EPT use for ≥ 5 years was seen only for serous (SIR 1.56; 95% CI 1.33-1.80) and mixed cancers (SIR 1.54; 95% CI 1.22-1.91), whereas the risk for mucinous cancer was decreased (SIR 0.47; 95% CI 0.22-0.86)., Conclusion: The elevated risk of non-mucinous ovarian cancer in users of EPT ≥ 5 years does not depend on progestin type, mode or route of administration of EPT.

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.

Introduction: We studied variation in incidence of cervix cancer during 1971-1995 among Finnish women born in 1906 to 1945 by social class and cell type., Material and Methods: The Finnish Cancer Registry data were linked to the 1970 Population Census, which included social class data. There were 0.8 million individuals in the cohort under follow-up, with 5,102 squamous cell cancers and 573 cases of cervical adenocarcinoma diagnosed after the census date., Results: Incidence of squamous cell cancer was more than two-fold in the lowest social class (standardized incidence ratio (SIR) 1.29, 95% CI 1.21-1.36) as compared with the highest one (SIR 0.59, 0.51-0.66), while there was no association between social class and risk on adenocarcinoma (SIR 1.07, 0.87-1.28 and 1.08, 0.79-1.45, respectively)., Discussion: Oncogenic HPV is regarded as the necessary cause of all types of cervix cancer. Sexually transmitted diseases and social status are correlated. Lack of association between adenocarcinoma and social class makes the HPV-etiology of this cell type less credible than that of squamous cell cancer.

We present up to 45 years of cancer incidence data by occupational category for the Nordic populations. The study covers the 15 million people aged 30-64 years in the 1960, 1970, 1980/1981 and/or 1990 censuses in Denmark, Finland, Iceland, Norway and Sweden, and the 2.8 million incident cancer cases diagnosed in these people in a follow-up until about 2005. The study was undertaken as a cohort study with linkage of individual records based on the personal identity codes used in all the Nordic countries. In the censuses, information on occupation for each person was provided through free text in self-administered questionnaires. The data were centrally coded and computerised in the statistical offices. For the present study, the original occupational codes were reclassified into 53 occupational categories and one group of economically inactive persons. All Nordic countries have a nation-wide registration of incident cancer cases during the entire study period. For the present study the incident cancer cases were classified into 49 primary diagnostic categories. Some categories have been further divided according to sub-site or morphological type. The observed number of cancer cases in each group of persons defined by country, sex, age, period and occupation was compared with the expected number calculated from the stratum specific person years and the incidence rates for the national population. The result was presented as a standardised incidence ratio, SIR, defined as the observed number of cases divided by the expected number. For all cancers combined (excluding non-melanoma skin cancer), the study showed a wide variation among men from an SIR of 0.79 (95% confidence interval 0.66-0.95) in domestic assistants to 1.48 (1.43-1.54) in waiters. The occupations with the highest SIRs also included workers producing beverage and tobacco, seamen and chimney sweeps. Among women, the SIRs varied from 0.58 (0.37-0.87) in seafarers to 1.27 (1.19-1.35) in tobacco workers. Low SIRs were found for farmers, gardeners and teachers. Our study was able to repeat most of the confirmed associations between occupations and cancers. It is known that almost all mesotheliomas are associated with asbestos exposure. Accordingly, plumbers, seamen and mechanics were the occupations with the highest risk in the present study. Mesothelioma was the cancer type showing the largest relative differences between the occupations. Outdoor workers such as fishermen, gardeners and farmers had the highest risk of lip cancer, while the lowest risk was found among indoor workers such as physicians and artistic workers. Studies of nasal cancer have shown increased risks associated with exposure to wood dust, both for those in furniture making and for those exposed exclusively to soft wood like the majority of Nordic woodworkers. We observed an SIR of 1.84 (1.66-2.04) in male and 1.88 (0.90-3.46) in female woodworkers. For nasal adenocarcinoma, the SIR in males was as high as 5.50 (4.60-6.56). Male waiters and tobacco workers had the highest risk of lung cancer, probably attributable to active and passive smoking. Miners and quarry workers also had a high risk, which might be related to their exposure to silica dust and radon daughters. Among women, tobacco workers and engine operators had a more than fourfold risk as compared with the lung cancer risk among farmers, gardeners and teachers. The occupational risk patterns were quite similar in all main histological subtypes of lung cancer. Bladder cancer is considered as one of the cancer types most likely to be related to occupational carcinogens. Waiters had the highest risk of bladder cancer in men and tobacco workers in women, and the low-risk categories were the same ones as for lung cancer. All this can be accounted for by smoking. The second-highest SIRs were among chimney sweeps and hairdressers. Chimney sweeps are exposed to carcinogens such as polycyclic aromatic hydrocarbons from the chimney soot, and hairdressers' work environment is also rich in chemical agents. Exposure to the known hepatocarcinogens, the Hepatitis B virus and aflatoxin, is rare in the Nordic countries, and a large proportion of primary liver cancers can therefore be attributed to alcohol consumption. The highest risks of liver cancer were seen in occupational categories with easy access to alcohol at the work place or with cultural traditions of high alcohol consumption, such as waiters, cooks, beverage workers, journalists and seamen. The risk of colon cancer has been related to sedentary work. The findings in the present study did not strongly indicate any protective role of physical activity. Colon cancer was one of the cancer types showing the smallest relative variation in incidence between occupational categories. The occupational variation in the risk of female breast cancer (the most common cancer type in the present series, 373 361 cases) was larger, and there was a tendency of physically demanding occupations to show SIRs below unity. Women in occupations which require a high level of education have, on average, a higher age at first child-birth and elevated breast cancer incidence. Women in occupational categories with the highest average number of children had markedly lower incidence. In male breast cancer (2 336 cases), which is not affected by the dominating reproductive factors, there was a suggestion of an increase in risk in occupations characterised by shift work. Night-shift work was recently classified as probably carcinogenic, with human evidence based on breast cancer research. The most common cancer among men in the present cohort was prostate cancer (339 973 cases). Despite the huge number of cases, we were unable to demonstrate any occupation-related risks. The observed small occupational variation could be easily explained by varying PSA test frequency. The Nordic countries are known for equity and free and equal access to health care for all citizens. The present study shows that the risk of cancer, even under these circumstances, is highly dependent on the person's position in the society. Direct occupational hazards seem to explain only a small percentage of the observed variation - but still a large number of cases - while indirect factors such as life style changes related to longer education and decreasing physical activity become more important. This publication is the first one from the extensive Nordic Occupational Cancer (NOCCA) project. Subsequent studies will focus on associations between specific work-related factors and cancer diseases with the aim to identify exposure-response patterns. In addition to the cancer data demonstrated in the present publication, the NOCCA project produced Nordic Job Exposure Matrix (described in separate articles in this issue of Acta Oncologica) that transforms information about occupational title histories to quantitative estimates of specific exposures. The third essential component is methodological development related to analysis and interpretation of results based on averaged information of exposures and co-factors in the occupational categories.

Introduction: The Nordic Occupational Cancer study (NOCCA) is a cohort study based on employed populations in one or more censuses in Denmark, Finland, Iceland, Norway and Sweden. The large size of the cohort allows us to study rare cancers and to identify even small risks by occupation and by specific occupational exposures. This paper describes principles and experiences of the construction of job-exposure matrices (JEMs), an instrument to transform the history of occupational titles into quantitative estimates of exposure to potential carcinogenic substances., Material and Methods: For each Nordic country, a national JEM was constructed by a team of experts on the basis of the Finnish matrix (FINJEM) that has been used in similar national studies since the mid-1990s., Results: The structure of the Nordic JEMs is three-dimensional (over 300 occupations, over 20 agents, 4 periods covering 1945-1994). Exposure is characterised by estimates of the prevalence and level of exposure. Important differences between the Nordic countries were observed for several exposures., Discussion: The selection of priority agent-occupation combinations and the adoption of general principles in the beginning of the work were necessary because of the high number of estimates to be evaluated (over 50 000/country). The selective modification of an existing JEM for use in other countries was a feasible, albeit challenging task, because exposure data and information about the use of chemicals in the past was scanty. As compared to the use of FINJEM for all Nordic countries, the modification process will probably increase the validity of dose-response and risk estimates of occupational cancer which is to be expected soon as the main outcome of the NOCCA project.

Unlabelled: Earlier studies have shown that cancer risk is related to educational level in many countries. The relationship between education and cancer risk has not been studied in the small, but ethnically homogenous, Icelandic population postulated to be outstanding as regards social equity., Material and Methods: We conducted a follow-up study of a cohort of 60,194 males and 58,505 females aged 20-64 at census 1981 in Iceland. Information on education from the census was classified into three educational groups and linked with the population-based Icelandic Cancer Registry. Standardized incidence ratios (SIRs) were calculated for the period 1982 to 2004., Results: We found a significant association between educational level and cancer risk. Among males with academic education, the SIR was elevated for prostate cancer (SIR=1.17, 95% CI 1.05-1.30) and melanoma (SIR=1.41, 95% CI 1.00-1.93) and lowered for cancers of the lung (SIR=0.72, 95% CI 0.59-0.87) and stomach (SIR=0.67, 95% CI 0.48-0.90). Women with academic education had an increased risk of breast cancer (SIR=1.19, 95% CI 1.07-1.33) and a decreased risk of lung cancer (SIR=0.49, 95% CI 0.36-0.65). Increasing educational level was associated with a lowered risk of cervical cancer (p trend=0.017)., Discussion: The association between education and cancer incidence seen in this study resembles observations from other countries and probably reflects concordance between social status and certain risk factors for cancer. Our study confirms health-related socioeconomic differences in Iceland and must be taken into account when programmes for health promotion are planned.

Validity of biobank studies on hormone associated cancers depend on the extent the sample preservation is affecting the hormone measurements. We investigated the effect of long-term storage (up to 22 years) on immunoassay measurements of three groups of hormones and associated proteins: sex-steroids [estradiol, progesterone, testosterone, dihydroepiandrosterone sulphate (DHEAS), sex hormone-binding globulin (SHBG)], pregnancy-specific hormones [human chorionic gonadotropin (hCG), placental growth hormone (pGH), alpha-fetoprotein (AFP)], and insulin-like growth factor (IGF) family hormones exploiting the world largest serum bank, the Finnish Maternity Cohort (FMC). Hormones of interest were analyzed in a random sample of 154 Finnish women in the median age (29.5 years, range 25 to 34 years) of their first pregnancy with serum samples drawn during the first trimester. All hormone measurements were performed using commercial enzyme-linked- or radio-immunoassays. Storage time did not correlate with serum levels of testosterone, DHEAS, hCG, pGH and total IGFBP-1. It had a weak or moderate negative correlation with serum levels of progesterone (Spearman's ranked correlation coefficient (r(s))=- 0.36), IGF-I (r(s)=-0.23) and IGF binding protein (BP)-3 (r(s)=-0.38), and weak positive correlation with estradiol (r(s)=0.23), SHBG (r(s)=0.16), AFP (r(s)=0.20) and non-phosphorylated IGF binding protein (BP)-1 (r(s)=0.27). The variation of all hormone levels studied followed the kinetics reported for early pregnancy. Bench-lag time (the time between sample collection and freezing for storage) did not materially affect the serum hormone levels. In conclusion, the stored FMC serum samples can be used to study hormone-disease associations, but close matching for storage time and gestational day are necessary design components of all related biobank studies.

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.

Unlabelled: The aim of the study was to assess the feasibility of and possible selection to attend in colorectal cancer screening., Material and Methods: During the years 1979-1980, 1 785 men and women (born in 1917-1929) were invited to a pilot screening project for colorectal cancer. The screening method used was a guaiac-based faecal occult blood test repeated once if the initial test was positive., Results: Compliance was 69% and the test was positive in 19% of those attending. In a record linkage with the Finnish Cancer Registry, 47 colorectal cancer cases and 24 deaths from colorectal cancer were observed by the end of 2004. In all, the particular test method was not regarded specific enough for population screening. There was, however, no difference in cancer incidence between those who complied and those who did not when compared to the general population of same age and gender., Conclusion: Compliance was found high enough to make screening feasible and there was no self selection of persons with low cancer risk to attend screening.

Human biomonitoring of the lipid peroxidation DNA modification 1,N6-ethenodeoxyadenosine (epsilondA) excreted into urine is thought to be a potential marker for oxidative stress-related DNA damage and human cancer. We have tested this hypothesis in a prospective, nested case-control study. During the years 1984-1989, 24-h urines were collected from 1956 men in the Kuopio Ischaemic Heart Disease (KIHD) Risk Factor Study. epsilondA concentrations were measured by LC-MS/MS in 24-h urine samples from 47 men with cancer diagnosed at follow up until 2001 and from 31 cancer free smoking-matched control subjects. Odds ratio for having higher than control median epsilon dA excretion rate and cancer, estimated by binary logistic regression, was 0.73 (95% CI 0.29-1.80, p = 0.49). In this study, the urinary excretion of epsilondA provides no additional prediction of cancer development in males after controlling for smoking.

We evaluated the accuracy and time to reporting of cancer diagnoses obtained through the Finnish Cancer Registry (FCR) for the Alpha-Tocopherol Beta-Carotene Cancer Prevention (ATBC) Study in 1985-1997. In the ATBC Study suspect neoplasms were centrally reviewed through medical records and pathology specimens. The FCR data were compared against the reviewed data for 3600 cancers of eight sites. For most sites, 95% of the cases were reported to the FCR within 0.9 years with longer delays for lung and pancreatic cancers. Ninety-six percent of all FCR cases received the same primary site diagnosis in the ATBC review, and in 1.4% no malignancy was found. Conversely, 97% of cancers ascertained in the ATBC review had the same primary site in the FCR and 0.8% were unknown to the Registry. The accuracy of the FCR data is high but the delay in case notification should be considered in epidemiological studies.

The decreasing incidence rate and improvement in survival of laryngeal cancer patients in Finland are exceptions among western countries. A descriptive study of these trends was conducted including both nationwide population-based cancer registry data with 5 766 patients diagnosed in 1956-1995 and regional hospital-based data from Northern Finland, allowing classification into supraglottic and glottic cancers, with 353 patients diagnosed in 1976-1995. In Finland, the age-adjusted incidence rate among males decreased from 6.5 per 100 000 in 1956-1965 to 3.5 in 1986-1995, while in females the rate remained around 0.3 per 100 000. The rates in Northern Finland were slightly higher and the supraglottic to glottic incidence ratio diminished from 1.4:1 in 1976-1985 to 0.5:1 in 1986-1995. The 5-year relative survival rate improved in both Northern Finland and the whole country, most noticeably among males and the elderly. In the data from Northern Finland, the survival rate was more favourable in glottic (80%) than in supraglottic cancer (64%). Considering the marked decrease in the incidence of the less favourable supraglottic disease, the observed improvement in survival was small.

A longitudinal cohort study was carried out to determine whether gynaecological infections other than human papillomavirus (HPV) are also related to the subsequent increased risk of cervical neoplasia. The study comprised 19114 women attending the organized mass screening in Finland in 1985-1990 with cytologically detected HPV, Actinomyces, herpes simplex, Trichomonas vaginalis, or yeast. The women were followed-up for subsequent preinvasive lesions and invasive cancers until the end of 1994 by linkage to the nation-wide Cancer Registry. Standardized incidence ratios (SIR) with rates for the whole of Finland as reference and 95% confidence intervals (CI) were estimated. Trichomonas vaginalis and HPV were associated with a high relative risk of cervical cancer, SIR 6.4 (CI 3.7-10, preinvasive lesion and invasive cancer combined) and SIR 5.5 (CI 4.2 7.2, preinvasive lesion and invasive cancer combined), respectively. Herpes simplex was rarely detected, but the highest and statistically most significant point estimate was observed (SIR 12, CI 2.4-34, preinvasive lesion and invasive cancer combined). Neither Actinomyces nor yeast was associated with a significantly increased risk of cervical cancer. None of these results could be accounted for by the confounding effect of the other infections. Our results, based on a prospective design, lead us to propose that Trichomonas vaginalis and herpes simplex virus are also predictors for cervical neoplasia.

In Finland traditionally as many as two-thirds of laryngeal cancers have been considered to be supraglottic, while in other countries the majority are glottic. The Finnish observation is based on clinical series diagnosed and treated mainly before the 1960s. The aim of our study was to evaluate the present situation. This study consisted of 279 patients treated in Eastern Finland between 1975 and 1994 and included 145 (52%) glottic, 124 (44%) supraglottic and 10 (4%) subglottic tumours in 260 (93%) men and 19 (7%) women. During this study period, the proportion of glottic tumours remained stable in men but increased in women. The change in smoking habits seems to be the most important reason for the shift from supraglottic to glottic tumours.

Introduction: The study of survival of cancer patients is essential for monitoring the effectiveness of cancer control. The previous monograph describing cancer patient survival in Finland was published by the Finnish Cancer Registry in 1981 and covered patients diagnosed in 1953-1974. This new supplement assesses cancer patient survival up to the year 1995., Material and Methods: The study includes over 560000 tumours registered at the Finnish Cancer Registry with a date of diagnosis between 1955 and 1994. Patients were followed up to the end of 1995. Trends in relative survival rates are studied over four 10-year diagnostic periods from 1955 to 1994. In addition, detailed results are presented for patients diagnosed during 1985-1994, including relative survival rates tabulated by stage, sex, and age. Additional sections describe differences in cancer patient survival according to social class and region of residence and a comparison of cancer patient survival in Finland to other European countries., Results: Patient survival improved over time for almost all anatomical sites. The main exception is in cancer of the cervix uteri, where patient survival has decreased slightly from 1965-1974 to 1985-1994 due to the selective prevention of less aggressive tumours through cytologic screening. Very few differences in patient survival are observed between males and females. A substantial improvement in survival can be seen for childhood cancers., Conclusion: The increasing survival rates reflect improvements that have taken place in various areas of cancer control, from health education and early diagnosis to treatment and aftercare. This study provides valuable reference information for both clinicians and health administrators, as well as a baseline for more detailed studies of patient survival for individual anatomical sites.

A population-based descriptive study was conducted to describe incidence and survival of cancer of the mobile tongue in Finland between 1953 and 1994. The study included 1504 patients, drawn from the Finnish Cancer Registry, with first primary mobile tongue cancer diagnosed between 1953 and 1994. Incidence and relative survival were determined. The age-standardized overall incidence rate was 0.6 per 100000 years in 1953-1994. At the time of diagnosis 78% of the patients had either localized or regional disease. The age-standardized incidence rate decreased after the mid-1960s, but increased in the 1990s. The 5-year relative survival rate increased gradually from 40% in 1953 1959 to 58% in 1988-1994. Disease stage at the time of the diagnosis strongly affected the survival rate. Survival increased especially in regional disease. Cancer of the mobile tongue is increasing in Finland, but survival has increased particularly in regional disease, probably because of improved treatment. Early diagnosis is emphasized for a good prognosis.

The effects of primary site, sex, age, stage and histological type on cancer patient survival were analysed on the basis of the population-based material of the Finnish Cancer Registry from 1985 to 1994. In addition, trends in survival were constructed for the period 1955-1994. Detailed site-specific data are published as Supplement 12 to Vol. 38 of Acta Oncologica. Within a given site, the survival differences by gender were not large. However, because of different site distributions, the average prognosis for female patients, all sites taken together, was superior to that of males: the 5-year relative survival rates (RSR) were 58% and 43%, respectively. In general, older patients had a poorer outcome compared with younger patients (partly because of different stage and histology distributions). Stage was a strong determinant of patient survival. In some cancers with a poor average prognosis the 5-year RSR for localized tumours was reasonable, e.g. 61% for stomach cancer, males, 34% for gallbladder cancer, females, and 29% for lung cancer, males. Most of the survival rates clearly increased over time. In addition to improvements in cancer treatment, changes over time in several other factors affect the trends, such as changes in the stage distribution (early diagnosis as a result of health education, improved diagnostic methods, screening, etc.) and in the composition of the patient material because of changing definitions of cancer (e.g. papilloma versus papillary carcinoma of the bladder, occult carcinoma of the thyroid, and early prostate cancer). The large Cancer Registry material (466,000 patients) enabled accurate estimates of the survival rates of cancer patients in Finland. These rates reflect the effectiveness of the healthcare system as a whole and are useful for planning and evaluation purposes. However, the estimated survival rates are based on grouped data, and cannot be directly applied for predicting the prognoses of individual patients, although they can be used as guidelines.

The risk of a second cancer among lung cancer patients was investigated using Finnish Cancer Registry data from 1953 to 1989. Among the 36,528 patients with a primary cancer of the lung, 504 new cancers were diagnosed six months or more after the diagnosis of lung cancer, yielding a standardized incidence ratio significantly lower than expected (SIR = 0.81). A significant excess of cancers of the larynx (SIR = 2.10) and urinary bladder (SIR = 1.35) was observed Among lung cancer patients below 60 years of age, the risks of oesophageal cancer (SIR = 2.47) and kidney cancer (SIR = 2.48) were also significantly elevated. The risk of a second cancer among lung cancer patients increased with the length of follow-up, and there was some indication of an excess risk of oesophageal cancer and leukaemia among lung cancer patients subject to radiotherapy.

Cancer registries should pay great attention to the quality of their data, both in terms of completeness (all cancer patients in the population are registered) and accuracy (data on individual cancer patients must be correct). In addition to technical measures in the data processing, different types of checks and comparisons should be routine practice. Active research policy and ambitious, research-oriented staff with competence in medicine, biostatistics and computer science are essential in terms of maintaining good data quality.

Bronchial asthma itself or the treatment of asthma may modify the immunological response to cancer. The survival of lung cancer patients with a preceding diagnosis of bronchial asthma was compared with that of non-asthmatic lung cancer patients in Finland during 1970-1989. This was accomplished by linking two nation-wide data registers, the medication reimbursement register and the cancer registry. For 921 out of the 926 asthmatic patients with lung cancer diagnosed after the diagnosis of bronchial asthma, a non-asthmatic referent patient, matching with respect to sex, anatomical site, and histological type of tumour, as well as to age and year of lung cancer diagnosis, was successfully found in the files of the Cancer Registry. Another referent group was formed by using the stage of lung cancer at diagnosis as an extra matching criterion; this search was successful for 895 asthmatic lung cancer patients. The corrected 5-year survival rate of asthmatic lung cancer patients was 8.4% and that of the referent patients, not matched for stage, 9.6%. When stage was included as matching criterion the corresponding rates were 8.5% and 8.1% respectively. None of these differences were significant. The prognosis of asthmatic and non-asthmatic lung cancer patients thus seemed to be similar.

A retrospective follow-up study on 924 physical education (PE) and 3,239 language (L) teachers was performed to study whether life-long high physical activity affects the risk of breast cancer. The Finnish Cancer Registry found 128 malignant breast cancers among these women in a follow-up during 1967-1987. The standardized incidence ratio (SIR) for all PE teachers was 1.28 (n.s.) and for L teachers 1.59 (p less than 0.001). Before the menopause (below age 50) SIR for PE teachers was 0.93 (n.s.) and for L teachers 1.51 (p less than 0.05). These results suggest that before menopause the risk of breast cancer in physically active PE is smaller than in the less active L. A Poisson regression analysis, taking into account the reproductive factors together with age and observation period, did not show any significant difference between PE and L teachers, probably due to the relatively small number of cases (n = 22) in the PE teacher group.