Showing papers by "Olof Nyrén published in 1999"
TL;DR: There is a strong and probably causal relation between gastroesophageal reflux and esophageaal adenocarcinoma, and the relation between reflux And gastric cardia is relatively weak.
Abstract: Background The causes of adenocarcinomas of the esophagus and gastric cardia are poorly understood. We conducted an epidemiologic investigation of the possible association between gastroesophageal reflux and these tumors. Methods We performed a nationwide, population-based, case–control study in Sweden. Case ascertainment was rapid, and all cases were classified uniformly. Information on the subjects' history of gastroesophageal reflux was collected in personal interviews. The odds ratios were calculated by logistic regression, with multivariate adjustment for potentially confounding variables. Results Of the patients interviewed, the 189 with esophageal adenocarcinoma and the 262 with adenocarcinoma of the cardia constituted 85 percent of the 529 patients in Sweden who were eligible for the study during the period from 1995 through 1997. For comparison, we interviewed 820 control subjects from the general population and 167 patients with esophageal squamous-cell carcinoma. Among persons with recurrent sy...
2,949 citations
TL;DR: The primary aim was to precisely estimate the strength of the association while adjusting for potential confounding factors, and the effects of body mass early in life compared with its effects late in life and assessed the relative importance of physical activity and energy intake.
Abstract: The association between body mass index and esophageal carcinoma was strong and was not explained by bias or confounding. The carcinogenic mechanism, however, remains to be clarified. The increasin...
675 citations
TL;DR: In comparison with the general population, patients with diabetes mellitus have an increased risk of renal cell cancer, and a higher risk was seen for kidney cancer mortality.
Abstract: To investigate the relation between diabetes mellitus and the risk of renal cell cancer we carried out a population-based retrospective cohort study. Patients identified in the Swedish Inpatient Register who were discharged from hospitals with a diagnosis of diabetes mellitus between 1965 and 1983 formed a cohort of 153 852 patients (80 005 women and 73 847 men). The cohort members were followed up to 1989 by record linkage to three nation-wide registries. Standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) were computed using age-specific sex-specific and period-specific incidence and mortality rates derived from the entire Swedish population. After exclusion of the first year of observation, a total of 267 incidences of renal cell cancer (ICD-7 : 180.0) occurred in diabetic patients compared with the 182.4 that had been expected. Increased risks were observed in both women (SIR = 1.7, 95 % confidence interval, CI = 1.4–2.0) and men (SIR = 1.3; 95 % CI = 1.1–1.6) throughout the duration of follow-up (1–25 years). A higher risk was seen for kidney cancer (ICD-7 : 180) mortality (SMR = 1.9; 95 % CI = 1.7–2.2, women; SMR 1.7, 95 % CI = 1.4–1.9, men). In comparison with the general population, patients with diabetes mellitus have an increased risk of renal cell cancer. [Diabetologia (1999) 42: 107–112]
219 citations
TL;DR: In this article, the authors reported dramatic increases in gastric cardia cancer incidence warrant concern, and the recent introduction of a separate diagnostic code, the lack of a consensus definition of t...
Abstract: Background: Reports of dramatic increases in gastric cardia cancer incidence warrant concern. However, the recent introduction of a separate diagnostic code, the lack of a consensus definition of t ...
192 citations
TL;DR: Examination of associations of physical activity, weight and weight change, fruit, vegetable, and alcohol consumption, socio‐economic status, parity and presence of diabetes mellitus with the risk of endometrial cancer in a cohort study confirmed that environmental factors are the most important, especiallyPhysical activity, parity, and weight in young and middle age.
Abstract: Case-control studies of lifestyle factors have been inconclusive in the study of endometrial cancer, and prospective data are scarce. Our aim was to examine the associations of physical activity, weight and weight change, fruit, vegetable, and alcohol consumption, socio-economic status, parity and presence of diabetes mellitus with the risk of endometrial cancer in a cohort study. In 1967, 11,659 women in the Swedish Twin Registry, born 1886–1925, answered a 107-item questionnaire, including questions about diet, physical activity and other lifestyle factors. Complete follow-up through 1992 was attained through record linkage to the Swedish Cancer and Death Registers. The relative risks for endometrial cancer were estimated in proportional hazards models that adjusted confidence limits for correlated outcomes. We observed 133 incident cases of endometrial cancer in the cohort. There was no clear pattern of risk over strata of alcohol or fruit and vegetable intake, although the data suggest an increased risk with very low fruit and vegetable intake. Increasing physical activity markedly decreased the risk of endometrial cancer (p for trend < 0.01), independently of weight and parity; the risk in the highest quartile, relative to the sedentary category, was 0.2 (95% CI 0.3–0.8). As expected, higher weight in middle age increased the risk (p for trend < 0.01), as did higher weight in early adulthood. Contrary to previous findings, weight gain did not have an effect independent of weight at enrollment. We did not find a genetic component to endometrial cancer. Our results confirm that environmental factors are the most important, especially physical activity, parity, and weight in young and middle age. Int. J. Cancer 82:38–42, 1999. © 1999 Wiley-Liss, Inc.
159 citations
TL;DR: This study did not support the hypothesis that the role of tobacco differs by sub‐site and histologic sub‐type of gastric cancer, and neither intake of alcoholic beverages nor snuff dipping was associated with an increased risk of any type of cardia or Gastric cancer.
Abstract: Few studies have provided information on the role of smoking and alcohol in the carcinogenesis of gastric cancer by sub-site and histologic type. The relationship of snuff dipping with risk of gastric cancer has also been rarely studied. In a population-based case-control study conducted in 5 counties of Sweden from February 1989 to January 1995, a total of 90 cases of gastric cardia cancer, 260 and 164 cases of distal gastric cancer of intestinal and diffuse types, respectively, and 1164 frequency-matched control subjects were personally interviewed about life-time smoking, use of smokeless tobacco and use of alcohol 20 years ago. Current smokers had a higher risk than never-smokers for all 3 kinds of gastric adenocarcinoma [odds ratio (OR) 1.7, 95% confidence interval (CI) 1.0-3.1 for gastric cardia adenocarcinoma; OR 1.8, 95% CI 1.2-2.7 for distal gastric cancer of intestinal type; and OR 2.2, 95% CI 1.4-3.5 for distal gastric cancer of diffuse type], and the risk rose with increasing dose and duration of smoking among current smokers. However, no elevated risk was observed for ex-smokers. Neither intake of alcoholic beverages nor snuff dipping was associated with an increased risk of any type of cardia or gastric cancer. Our study did not support the hypothesis that the role of tobacco differs by sub-site and histologic sub-type of gastric cancer.
123 citations
TL;DR: Data on individual exposure are not consistent with an important role of sunlight in the etiology of NHL, but some support is provided for an association of sunlight exposure with NHL incidence based on the associations seen using geographic latitude of residence as a proxy for exposure.
Abstract: Indirect evidence, notably ecological comparisons and an association with skin cancer, links non-Hodgkin's lymphoma (NHL) with exposure to sunlight. We conducted a population-based, nationwide cohort study with exposure to outdoor work inferred from job titles reported in the population and housing censuses in 1960 and/or 1970 and by classifying each individual's work and home addresses according to latitude. Follow-up for cancer incidence was accomplished through record linkages with the virtually complete Swedish Cancer Registry. The cohort included all Swedish residents who were recorded as gainfully employed in both censuses. Altogether 4,171,175 individuals contributing 69,639,237 person-years accrued through 1989 were included in the analyses. We identified 10,381 cases of NHL, 4,018 cases of chronic lymphocytic leukemia (CLL), 11,398 cases of malignant melanoma (MM) and 11,913 cases of squamous cell skin cancer (SCC). We calculated age-adjusted relative risks for NHL, CLL, MM and SCC in strata based on estimated residential and occupational sunlight exposure. Interaction effects were considered for pesticide and solvent exposure. NHL, MM and SCC, but not CLL, were positively associated with increasingly southerly residential latitude, with stronger associations seen for skin cancer compared to NHL. Occupational sun exposure was not associated with the risk of developing any of the studied cancers. Pesticides and solvents also were not related to an increased risk of NHL, nor did these exposures enhance effects of residential or occupational sunlight exposure. Our results provide some support for an association of sunlight exposure with NHL incidence based on the associations seen using geographic latitude of residence as a proxy for exposure. Although type of occupation may be an imperfect index of the biologically relevant ultraviolet (UV) light dose, our data on individual exposure are not consistent with an important role of sunlight in the etiology of NHL.
121 citations
TL;DR: The increasedrisk of primary liver cancer and the increased risk of mortality from cirrhosis of the liver are consistent with findings from previous clinical surveys, but the new observations of excess lung cancer and chronic obstructive pulmonary disease require confirmation.
Abstract: Cancer incidence and mortality risks were evaluated in a combined cohort of patients who were hospitalized for porphyria in Denmark (1977-1989) and Sweden (1965-1983) Patients were identified by using population-based hospitalization registries The unique individual identification numbers of 530 patients with porphyria cutanea tarda (PCT) and 296 with acute intermittent porphyria (AIP) were linked to the nationwide cancer and death registries Among patients with both types of porphyria, the authors found small but significantly elevated risks of all cancers combined (PCT: standardized incidence ratio (SIR) = 17, 95% confidence interval (CI) 13-22; AIP: SIR = 18, 95% CI 11-28) due to pronounced excesses of primary liver cancer (PCT: SIR = 212, 95% CI 85-437; AIP: SIR = 704, 95% CI 227-1643) and moderate increases in lung cancer (PCT: SIR = 29, 95% CI 15-52; AIP: SIR = 28, 95% CI 03-102) PCT patients had a significantly increased risk of mortality from liver cirrhosis (standardized mortality ratio (SMR) = 84, 95% CI 31-184) or chronic obstructive pulmonary disease (SMR = 31, 95% CI 11-67) The increased risk of primary liver cancer and the increased risk of mortality from cirrhosis of the liver are consistent with findings from previous clinical surveys, but the new observations of excess lung cancer and chronic obstructive pulmonary disease require confirmation
88 citations
TL;DR: The survival of patients with a stomach cancer diagnosis appears to be increasing, likely to include improvements in surgical and anesthesiologic management, but the long-term prognosis of cancer of the gastric cardia remains dismal.
Abstract: The overall survival among patients with stomach cancer has remained stable at a depressingly low level for several decades. 1,2,3–5 Hopes that a true change in the overall prognosis may be imminent have been raised, however, by the increased availability of endoscopy 6,7 and encouraging reports from case series, which have documented an increasing proportion of surgical resections, 8,9 decreasing operative mortality rates, 10 and increasing long-term survival among those operated on for cure. 8,9
Population-based studies of the overall survival among patients with stomach cancer have been sparse. 3–5,11 Only hospital-based case series have provided survival data for cancer of the gastric cardia, 12–14 which appears to be epidemiologically 15–17 and clinically 18 distinct from noncardiac stomach cancer. The aim of the present study, based on the entire population of Sweden, was to test the hypothesis that advances in diagnosis and treatment have increased the overall survival among patients with cardiac and noncardiac cancer of the stomach.
84 citations
TL;DR: There is no evidence of a positive association between HPV16 or HPV18 infection and either form of esophageal cancer, and the results do not support conclusions from previous studies.
Abstract: Background: Infection with human papillomavirus (HPV) type 16 has been implicated as a risk factor for esophageal squamous cell carcinoma in three seroepidemiologic studies. We conducted a larger, population-based study to verify this association and to i
74 citations
TL;DR: These nationwide results indicate no overall cancer hazard among hip and knee implant patients, but limited follow-up warrants continued surveillance of individuals undergoing these increasingly common surgical procedures.
Abstract: A nationwide cohort study of hip and knee replacement patients in Denmark was undertaken to assess any carcinogenic potential of these implants. A cohort of 22,997 osteoarthritis patients who received hip replacements and of 4,771 osteoarthritis patients who received knee replacements during the period 1977 through 1989 were identified using the nationwide Danish Hospital Discharge Registry. These patients were followed for cancer occurrence through 1993, using the Danish Cancer Registry. There was no overall excess of cancer in either the hip implant cohort [standardized incidence ratio (SIR) = 0.94; 95% confidence interval (CI)= 0.91-0.98] or the knee implant cohort (SIR = 0.97; 95% CI = 0.89-1.06). The risk reduction in both groups of patients reflected for the most part reduced risks for cancers of the respiratory system and the digestive tract, particularly stomach cancer (SIR = 0.69; 95% CI = 0.50-0.81 for hip replacement patients; SIR = 0.46; 95% CI = 0.20-0.91 for knee replacement patients). Elevated risks were observed for melanoma of the skin in both groups of patients. There was no clear excess risk for lymphohematopoietic cancers or malignant neoplasms of the bone or connective tissue among implant patients in either implant group. Contrary to an earlier study in Sweden, we did not find an excess risk for kidney or prostate cancers. In summary, these nationwide results indicate no overall cancer hazard among hip and knee implant patients, but limited follow-up warrants continued surveillance of individuals undergoing these increasingly common surgical procedures.
TL;DR: Genomic fingerprinting showed extensive interpatient variation, but the banding pattern obtained from colonies from the same patient were always identical (intrapatient variation), while in five patients, the cagA status varied between the colonies despite identical banding patterns.
Abstract: The aim of the study was to determine inter- and intrapatient variation of Helicobacter pylori strains based on genomic fingerprinting and cagA (cytotoxin-associated gene A) status. Ten bacterial colonies from each of 10 patients with gastric cancer (GC), 10 with duodenal ulcer (DU), and 10 with gastritis (GI) were used. The presence of the putative adhesin gene, the cagA gene, and the strain specific banding pattern obtained by arbitrary primed (AP-) PCR was analyzed. Genomic fingerprinting showed extensive interpatient variation, but the banding patterns obtained from colonies from the same patient were always identical (intrapatient variation). In five patients, the cagA status varied between the colonies despite identical banding patterns. Among patients in a developed country such as Sweden, the proportion with multiple-strain infection of H. pylori is low, but subclones with differing cagA status exist within the strain.
Journal Article•
TL;DR: Employment in the metal industry and exposure to phenoxyacetic acids were both positively and independently associated with gastric cancer risk and the fractions of all gastric cancers attributable to these job-related exposures were small but not negligible in the Swedish population.
Abstract: Gastric cancer trends seem to follow improvements in the environment of blue-collar workers, but the etiological role of occupational exposures in gastric carcinogenesis is scantily investigated. The risk of gastric adenocarcinoma in 10 common occupational industries, and particularly the long-term effects of asbestos, organic solvents, impregnating agents, insecticides, and herbicides, were evaluated in a population-based case-control study, including data on most established risk factors. The study base included all individuals of ages 40-79, born in Sweden and living in either of two areas (total population, 1.3 million) with differing gastric cancer incidences, from February 1989 through January 1995. We interviewed 567 cases classified to site (cardia/noncardia) and histological type, and 1,165 population-based controls, frequency-matched for age and sex. Metal workers had a 46% excess gastric cancer risk [adjusted odds ratio (OR), 1.46; 95% confidence interval (CI), 1.10-1.94], increasing to 1.65 (95% CI, 1.17-2.32) for >10 years in the industry. The elevated risk after exposure to herbicides (OR, 1.56; 95% CI, 1.13-2.15) was attributable to phenoxyacetic acids (adjusted OR, 1.70; 95% CI, 1.16-2.48), similarly across tumor subtypes, and not modified by smoking, body mass index, or Helicobacter pylori. The absence of interaction was demonstrated by the pure multiplicative effect found among those exposed to both H. pylori and phenoxyacetic acids (OR, 3.42; 95% CI, 1.41-8.26). Organic solvents, insecticides, impregnating agents, and asbestos were not associated with gastric cancer risk. Employment in the metal industry and exposure to phenoxyacetic acids were both positively and independently associated with gastric cancer risk. The fractions of all gastric cancers attributable to these job-related exposures were small but not negligible (7 and 5%, respectively) in the Swedish population.
TL;DR: The protective effect of occupational physical activity on breast cancer risk, if any, appears to be confined to certain age groups.
Abstract: Objective: Our purpose was to investigate effects of physical activity on risk for breast cancer
TL;DR: Occupational physical activity was inversely associated with renal cell cancer among men, and the absence of association among women might be due to smaller range of exposure, confounding by household work or reproductive factors, or to a difference in biological response to physical activity in men and women.
Abstract: The causes of renal cell cancer remain incompletely understood. In one previous retrospective case-control study, high occupational physical activity has been associated with a decreased risk among men, but not among women. Our aim was to investigate the association between occupational physical activity and renal cell cancer in a large cohort in Sweden. A cohort of Swedish men and women was identified in the nationwide censuses in 1960 and 1970, and the reported occupations were classified into 4 levels of physical demands. Follow-up from 1971 through 1989 was accomplished through record linkages to the Swedish Cancer Registry. Multivariate Poisson regression models were used to estimate relative risk (RR) and 95% confidence intervals (CI). We found a monotonic increase in risk of renal cell cancer with decreasing level of occupational physical activity among men (p for trend 0.50). Occupational physical activity was inversely associated with renal cell cancer among men. The absence of association among women might be due to smaller range of exposure, confounding by household work or reproductive factors, or to a difference in biological response to physical activity in men and women.
TL;DR: The results show no general HWE for cancer incidence among employed Swedish women, and overall cancer risks were highest among full-time workers, younger workers, urban workers, and workers with the highest socioeconomic status.
Abstract: Background
Our aim was to evaluate whether there is a healthy worker effect (HWE) for cancer incidence among women. HWE is a bias found in occupational studies that compare rates of disease among employed people to disease rates for the general population, which includes unemployed people (who may be less healthy than those who are employed).
Methods
Data from the 1960 and 1970 Swedish censuses were used to identify all 1,659,940 Swedish women who were employed in either year. They were followed during 1971–1989 through linkages to the national cancer and death registers. Standardized incidence ratios (SIRs) were computed comparing employed women to the 1,627,873 women who were not employed in either 1960 or 1970.
Results
For the 545,857 women employed in both 1960 and 1970, the SIR for all cancers combined was 1.05 (1.04–1.06). When specific cancer sites were analyzed separately, the highest cancer risks were for cancers of the lung and bladder (SIR = 1.2) and reproductive organs (breast, ovary, endometrium, and cervix SIR = 1.1). Overall cancer risks were highest among full-time workers, younger workers, urban workers, and workers with the highest socioeconomic status (based on the woman's job title).
Conclusions
These results show no general HWE for cancer incidence among employed Swedish women. Am. J. Ind. Med. 36:193–199, 1999. Published 1999 Wiley–Liss, Inc.
TL;DR: Differences in outcome between catchment area categories could not be explained by differences in age, time period, or duration of follow up after diagnosis, and were attributable to different strategies for diagnosing and managing patients with rectal cancer.
Abstract: BACKGROUND—The quality of rectal cancer surgery at small units has been debated. No national studies of this issue have been undertaken and most studies have been based on insufficient data to clarify the controversy. It has been claimed that observed differences in outcomes between specialised centres and smaller hospitals are confounded by differences in stage/severity.
AIM—To compare survival after rectal cancer between hospital catchment areas.
PATIENTS—All patients with rectal cancer notified to the Swedish Cancer Register in 1973-1992 (n = 30 811) were followed up by record linkage to the nationwide Death Register.
METHODS—Relative survival—that is, ratio of observed to expected survival—was computed as a measure of excess mortality attributable to rectal cancer. Multivariate analysis was then performed to estimate the independent effects of hospital catchment area categories and age, year of diagnosis, and duration of follow up.
RESULTS—One year relative survival among rectal cancer patients residing in catchment areas of large regional hospitals was 76%, compared with 72% for small local hospitals (p<0.001). A difference was already noted after 30 days and remained five years after diagnosis. Relative survival improved considerably overall, but the differences between catchment area categories persisted. These were not reduced by adjustment for age, time after diagnosis, or time period in multivariate models.
CONCLUSION—The differences in outcome between catchment area categories could not be explained by differences in age, time period, or duration of follow up after diagnosis. They are unlikely to be explained by differences between catchment area populations with regard to the average stage of the disease at which symptoms lead to diagnosis. The differences may therefore be attributable to different strategies for diagnosing and managing patients with rectal cancer.
Keywords: rectal neoplasms; cancer; survival; Sweden
TL;DR: Results provide no support for a common link between colon cancer and oesophageal adenocarcinoma and suggest screening for colonic neoplasia among patients with malignant or premalignant oesophileal mucosa, or vice versa, may not be warranted.
Abstract: BACKGROUND—Previous reports have indicated an association between Barrett's metaplasia or adenocarcinoma of the oesophagus and colonic neoplasia, but the findings have been inconsistent. If true, such an association suggests common causal mechanisms.
AIMS—To test the hypothesis of an association between Barrett's metaplasia or adenocarcinoma of the oesophagus and colonic neoplasia.
METHODS—A population based, retrospective cohort study was performed on all Swedish patients with colon cancer diagnosed between 1958 and 1992. 538 500 person years at risk were reviewed among the 118 030 patients in the cohort (average follow up 4.6 years, median 2.1 years). The standardised incidence ratio (SIR), the ratio of the observed to the expected number of incident oesophageal adenocarcinomas, was used as a measure of relative risk. The expected number was derived from the entire Swedish population.
RESULTS—Eleven oesophageal adenocarcinomas were found during follow up in the cohort, as against 9.5 expected (SIR=1.2; 95% confidence interval 0.6-2.1). Analysis by latency intervals after diagnosis of colon cancer showed no trend towards increasing or decreasing risk over time. There were no important sex differences in relative risk.
CONCLUSIONS—Results provide no support for a common link between colon cancer and oesophageal adenocarcinoma. Although the direct relation between colon cancer and Barrett's oesophagus was not looked at, a search for common aetiological factors or genetic defects may not be fruitful. Screening for colonic neoplasia among patients with malignant or premalignant oesophageal mucosa, or vice versa, may not be warranted.
Keywords: oesophageal cancer; Barrett's metaplasia; colon cancer; adenocarcinoma