Biomedical subjects

R Bergström

Publications and source records attributed to R Bergström.

At least 73 records · Page 4Linked to original sources

PubMed1997

Influence of left ventricular function on survival after coronary artery bypass grafting.

BACKGROUND: Preoperative left ventricular function is a most important predictor for survival in patients with ischemic heart disease. To elucidate the optimal timing of recommended coronary artery bypass grafting, we investigated the influence of different aspects of preoperative left ventricular function on relative survival. METHODS: To calculate the relative survival and estimate the disease-specific survival, we compared 6,514 patients who survived the first month after primary coronary artery bypass grafting with the general Swedish population stratified by age, sex, and 5-year calendar period. In particular we studied the relation between relative survival and different aspects of left ventricular performance, namely left ventricular function at rest, New York Heart Association functional class, and number of previous myocardial infarctions. RESULTS: The three variables (left ventricular function at rest, New York Heart Association functional class, and number of previous myocardial infarctions) as well as age and follow-up year gave independent information concerning relative survival. The results from this multivariate analysis were used to define a risk score for each patient. Patients were categorized into different risk groups. Patients in the low-risk group (30% of the total) showed a survival better than that of the population at large for 9 years after operation. The medium-risk group had no or low excess mortality for about 7 years, and the high-risk group (25%) showed increased excess mortality immediately after operation. CONCLUSIONS: If primary coronary artery bypass grafting is performed before the left ventricular function and physical performance deteriorate, survival is excellent.

Actuarial Analysis↗

PubMed1997

Mammographic screening for breast cancer. What cancers do we find?

The aim of this study was to compare lymph node involvement of breast cancer cases detected at mammography screening with clinically-detected cases. During a 3-year period, 273 primary breast cancers were detected in a population-based screening programme, and 149 primary breast cancers were diagnosed clinically. Lymph node involvement was evaluated in univariate and multivariate logistic regression models correcting for tumour size, histological grade, steroid receptor status and DNA-ploidy. Patients with screen-detected cancers had a low relative risk of having lymph node metastases (univariate, OR = 0.31; 95% confidence interval = 0.19-0.52). In the multivariate logistic regression model, the relative risk was halved (OR = 0.47; 0.28-0.78). The reduced risk was more pronounced for women younger than 50 years of age compared to older women. The risk for screen-detected cases of having lymph node metastases at diagnosis was statistically significantly lower than for clinically-detected cases. The marked reduction, even when correcting for tumour size, makes it less likely that factors such as detection of clinically innocent tumours, length bias sampling or clinical symptoms related to axillary metastases can explain the whole difference. The results indicate at least part of the effect may be explained by tumour progression in the late preclinical detectable phase.

Adult↗

PubMed1997

Long-term relative survival after primary heart valve replacement.

OBJECTIVE: Determination of the optimal timing of primary heart valve replacement is an important issue. The present paper provides a synopsis over early and late survival after primary heart valve replacement, including an evaluation of the excess mortality among heart valve replacement patients compared with the general population. METHODS: Survival was analyzed in 2365 patients (1568 without and 797 with concomitant coronary artery bypass grafting (CABG)) who underwent their first heart valve replacement. Observed survival was related to that expected among persons from the general Swedish population stratified by age, sex, and 5-year calendar period, to calculate the relative survival and estimate the disease-specific survival. RESULTS: Early mortality (death within 30 days after surgery) was 5.9% after aortic valve replacement, 10.4% after mitral valve replacement and 10.6% after combined aortic and mitral valve replacement. Relative survival rates (excluding early deaths) were 84% 10 years after aortic, 68.5% after mitral and 80.9% after both aortic and mitral valve replacement. A multivariate model based on observed survival rates was produced for each group, using the Cox proportional hazards model. Concomitant CABG, advanced New York Heart Association (NYHA) class, preoperative atrial fibrillation, pure aortic regurgitation and higher age increased the late observed survival after aortic valve replacement. NYHA class was the only factor independently related to observed late deaths after mitral valve replacement, and mitral insufficiency the only corresponding factor after both aortic and mitral valve surgery. CONCLUSION: The use of relative survival rates tended to modify the difference between subgroups compared with observed survival rates. Relative survival rates reduced the effect of concomitant CABG on survival, but enhanced for example the effect of aortic regurgitation. In patients > or = 70 years of age and patients submitted to aortic or mitral valve replacement with mild or no symptoms, the survival rate was similar for many years to that in the Swedish population at large.

Adult↗

PubMed1997

Sternal wound complications--incidence, microbiology and risk factors.

OBJECTIVE: Sternal wound complications, i.e. instability and/or infection (mediastinitis), are important causes of morbidity in patients undergoing cardiac surgery via median sternotomy. Coagulase negative staphylococci, a normal inhabitant of the skin, have evolved as a cause of sternal wound infections. Since these opportunistic pathogens often are multiresistant, they can cause therapeutic problems. METHODS: From 1980 through 1995 open heart surgery, was performed on 13,285 adult patients. Reoperation necessitated by sternal wound complications occurerd in 203 patients (1.5%). The incidence was 1.7% (168/9987) after coronary artery bypass grafting (CABG group) and 0.7% (35/3413) after heart valve surgery with or without concomitant CABG (HVR group). RESULTS: Factors independently related to sternal complications in the CABG group (variable odds ratio [95% C.I.]): year of surgery, 1.9 [1.3-2.8] in 1990-1992, 2.0 [1.4-2.9] in 1993-1995; female sex, 0.4 [0.2-0.6]; diabetic disease, 1.8 [1.2-2.5]; bilateral ITA procedure, 3.3 [1.1-7.7]; and postoperative dialysis, 3.1 [1.4-6.9]. In the HVR group they were: use of ITA graft, 3.7 [1.7-7.7]; early re-exploration because of bleeding 3.0 [1.1-8.2]; and postoperative dialysis 3.1, [1.4-9.3]. Multivariate models were used to compute the risk for sternal complications in each patient. However, the prognostic models based on these risk scores provided low sensitivity and low predictive value. Patients with sternal wound complications showed no increased early mortality but worse long-term survival even after adjustment for other factors (relative hazard in CABG group 1.9 [1.2-2.8]; in HVR group 2.1 [1.1-4.3]. CONCLUSIONS: The use of ITA grafts seems to be one of the most important factors related to sternal wound complications. However, patients at truly increased risk for this complication could not be identified on the basis of the risk factors considered in this study.

Adult↗

PubMed1997

Risk for endometrial cancer following breast cancer: a prospective study in Sweden.

The risk for endometrial cancer among women with breast cancer might increase following use of tamoxifen, recently classified as a carcinogen of the human endometrium. However, the strength of the association remains uncertain and it is unknown whether use of this drug--widely prescribed in Sweden since the mid-1980s--has had any measurable effect at the population level. We analyzed all cases of breast cancer (n = 131,614) detected in the nationwide Swedish Cancer Registry in 1958-93. Incident cases of endometrial cancer during follow-up were identified also through the Cancer Registry. Standardized incidence ratios (SIR) and their 95 percent confidence intervals (CI) were computed by use of nationwide rates of endometrial cancer, adjusted for age and calendar year. During follow-up of up to 35 years of the breast cancer cohort, 803 incident endometrial cancers were identified, yielding an overall SIR of 1.58 (CI = 1.47-1.70). In univariate analyses, there was no increase in SIR in recent years. However, the excess risk increased linearly with increasing age at breast cancer diagnosis (P trend < 0.0001) and decreased markedly with longer follow-up (P trend < 0.0001). A multivariate regression analysis, with adjustment for age and year of follow-up, revealed no increased risk for subsequent endometrial cancer among breast cancer cases diagnosed more recently (P trend = 0.19); compared with the period 1958-63, the risk estimate in the last time period (1989-93) was 0.72 (CI = 0.51-1.01). We conclude that the risk for endometrial cancer following breast cancer has not increased over time in Sweden.

Adult↗

PubMed1997

Diet and the risk of papillary and follicular thyroid carcinoma: a population-based case-control study in Sweden and Norway.

A population-based case-control study was conducted in two regions of Sweden and Norway to investigate the association between dietary habits and the risk of thyroid cancer. The consumption of selected foods was reported in a self-completed food-frequency questionnaire by 246 cases with histologically confirmed papillary (n = 209) and follicular (n = 37) thyroid carcinoma, and 440 age- and gender-matched controls. Odds ratios (OR) and their 95 percent confidence interval (CI) were calculated as estimates of the relative risk using conditional logistic regression. High consumption of butter (OR = 1.6, CI = 1.1-2.5) and cheese (OR = 1.5, CI = 1.0-2.4) was associated with increased risks. Residence in areas of endemic goiter in Sweden was associated with an elevated risk, especially among women (OR = 2.5, CI = 1.3-4.9). High consumption of cruciferous vegetables was associated with increased risk only in persons who ever lived in such areas. A decreased risk was associated with consumption of iodized salt in northern Norway, and with use of iodized salt during adolescence among women (OR = 0.6, CI = 0.6-1.0). The results of this study suggest a role of diet and environment in the risk of thyroid cancer.

Adolescent↗

PubMed1997

Trends in urinary bladder cancer incidence in Sweden 1960-93 with special reference to histopathology, time period, birth cohort, and smoking.

This study investigates the incidence trends of urinary bladder cancer in Sweden from 1960 through 1993 (a total of 46,211 cases). Age-standardized incidence rates increased among men from 14.6 per 10(5) in 1960 to 33.5 in 1993 and among women from 4.8 to 8.8, corresponding to an average annual increase of 2.4 percent (95 percent confidence interval [CI]) = 2.0-2.7 percent) and 1.1 percent (CI = 0.9-1.4 percent), respectively. The largest increase occurred in the oldest age-groups. The proportion of patients with transitional cell carcinoma increased in men from 66.0 percent in 1960-64 to 93.6 percent in 1990-93 and in women from 61.0 percent to 89.4 percent. The proportion of patients with papillomas decreased, whereas those with adenocarcinoma and squamous cell carcinoma were stable. Regression modeling (based on the period 1960-89) showed a strong linear effect due to either period and/or cohort. Among men, additional non-linear effects by both period and cohort were obtained. The cohort effects were more important. Cohort data on having smoked daily showed considerable similarities with the estimated cohort-effects. Our findings suggest that the increase of tobacco smoking in successive generations can explain the increase in incidence rates of bladder cancer in Sweden, whereas improved diagnostic activities and registration are less likely to explain fully the changes in incidence rates.

Adult↗

PubMed1997

Stromal tenascin distribution as a prognostic marker in colorectal cancer.

A total of 169 colorectal adenocarcinomas, obtained from patients with a median follow-up of 6.5 years, were studied with immunohistochemical staining on cryosections using a monoclonal anti-tenascin antibody to evaluate the possible association between the staining patterns and tumour stage, tumour differentiation and survival. We found two different staining patterns in the tumour stroma--a diffuse stromal fibrillar staining in 92 out of 169 (54%) tumours and a subglandular staining in the remaining 77 tumours. When the entire group of patients (P < 0.01) and the group of potentially cured patients (P < 0.03) were analysed univariately, it was found that diffuse stromal fibrillar staining was associated with a shorter survival time than subglandular staining. In a multivariate analysis, the Dukes' stage and age were independent prognostic factors, whereas the tenascin expression did not retain a clear independent relationship to survival (P = 0.06). Hence, it appears that the tumour expression of tenascin may be a potential prognostic marker in colorectal cancer, in so far as a diffuse stromal fibrillar staining pattern seems to indicate an increased risk of poor outcome. However, after adjustment for age and Dukes' stage, the additional prognostic value of tenascin remains to be established in further analyses.

Adult↗

PubMed1997

Reliability of retrospective information on diet 20 years ago and consistency of independent measurements of remote adolescent diet.

Although dietary exposures in the distant past are considered important in the etiology of several diseases, few studies have addressed methodological aspects of long-term (> or = 20 yrs) recall. We evaluated the reliability of retrospective self-reports about diet 20 years before the interview and consistency (between siblings) of self-reports about diet during adolescence in a population-based case-control study of stomach cancer in Sweden. Short-term reliability (a questionnaire self-administered 9-12 mos after the personal interview) of reports on diet 20 years ago by 374 control subjects showed mean correlation coefficients for 42 foods/beverages of 0.41 (Pearson) and 0.46 (Spearman) and a mean weighted kappa statistic of 0.42; for 15 nutrients/food constituents the corresponding mean values were 0.46, 0.47, and 0.42, respectively. Consistency of independent reports by siblings about their own diet during adolescence studied in 201 control-sibling pairs was modest. The mean Pearson correlation coefficient for 33 foods/beverages was 0.29, and the mean weighted kappa statistic was 0.30; at the nutrient level the means were 0.26 and 0.24, respectively. A comparison of intersibling differences between controls and stomach cancer cases revealed correlations of a similar magnitude (mean Pearson correlation for 33 foods = 0.29 for control-sibling and 0.27 for case-sibling pairs), thus contradicting differential recall. Our results imply that although reliability of self-reports about the diet in the distant past is generally lower than for the actual diet, we can use these measurements when remote time periods are of special interest in etiological epidemiologic studies.

Adolescent↗

PubMed1997

Survival after colon cancer 1973-1990 in Sweden. Convergence between catchment areas.

OBJECTIVE: The objective of the study is to analyze the temporal trends in relative survival among patients with colon cancer in catchment areas of hospitals of different categories and regions in Sweden. BACKGROUND: In Sweden, cancer of the colon is the second most common type of cancer in women and the third most common in men, afflicting approximately 3000 individuals annually. During the past decades, survival has improved, but it is not clear what factors have contributed to this development. Changes in the natural history of the disease, altered alimentary habits, advances in diagnosis, and treatment have been suggested. The effects of centralized care still are debated. METHOD: Longitudinal observational study of relative survival of all patients with colon cancer from 1973 to 1993 in Sweden (n = 41,700) by period of diagnosis and hospital category of primary catchment area was conducted. Multivariate analyses of relative hazards of any interaction between length of follow-up, period of diagnosis, hospital category of the primary catchment area, age at diagnosis, and region were performed. RESULTS: Relative survival in patients with colon cancer improved substantially from 1973 through 1990. The prognosis in patients from primary catchment areas of regional-university hospitals did not change during this period, and the prognostic improvement was noted only in county and local hospital areas, where survival approached that of regional hospitals. Although new management regimens may have been introduced unevenly, improved perioperative care best explains this convergence. Low-incidence regions showed the lowest survival, but this improved with time, although not significantly. CONCLUSIONS: Although survival in patients with colon cancer improved and convergence between different catchment area categories was seen, a large initial gap as well as a remaining difference may warrant future monitoring to ensure equal prognosis, irrespective of domicile.

Aged↗

PubMed1997

Diet and risk of renal cell cancer: a population-based case-control study.

In a few previous studies on diet and renal cell cancer, an inconsistent positive association with meat, milk, and protein and a negative association with vegetable and fruit consumption have been found. Whereas earlier studies have dealt with recent diet only, our study explored the effect of foods consumed both during the usual adult lifetime and 20 years prior to interview. The study included 379 individuals with incident histologically verified renal cell cancer and 350 control subjects residing in eight counties in Sweden between June 1989 and December 1991. Usual adult dietary intake and dietary habits 20 years prior to interview were assessed by a structured face-to-face interview and a self-administered questionnaire, respectively. Odds ratios were estimated through unconditional logistic regression. We have not observed an association of renal cell cancer with milk or total meat consumption per se; however, frequent intake of fried/sautéed meat increased the risk of renal cell cancer by about 60%; frequent consumption of poultry was also associated with an increased risk (P for trend, 0.05). A significantly protective effect on risk of renal cell cancer was observed with increasing consumption of fruit (P for trend, 0.05). When analyzed by smoking status, total fruit and especially citrus fruit consumption among nonsmokers showed an even stronger protective effect; the highest quartiles of total fruit, apple, and citrus fruit consumption entailed a 50-60% reduction in risk of renal cell cancer compared with the lowest quartiles. There was a suggestion of a protective effect of high total vegetable consumption. A protective effect of vitamin C and alpha-tocopherol was also more pronounced in nonsmokers (P for trend, 0.004 and 0.007, respectively). Our study adds to the evidence that diet may have an important role in the etiology of renal cell cancer.

Aged↗

PubMed1996

Energy, nutrient intake and prostate cancer risk: a population-based case-control study in Sweden.

The role of diet in the etiology of prostate cancer remains unclear, because results from several case-control and cohort studies on fat intake and risk of prostate cancer have been inconsistent; few of the studies have adjusted the results for caloric intake. To examine the relationship between energy, intake of several nutrients and risk of prostate cancer (all stages combined and advanced stages separately), we conducted a population-based case-control study in Orebro County, Sweden, from 1989 through 1994. A total of 526 patients with newly diagnosed prostate cancer and 536 controls, randomly selected from the population register and frequency-matched by age, were included in the analyses. Information about dietary intake was obtained from a self-administered semi-quantitative food frequency questionnaire. Odds ratios with 95% confidence intervals were estimated by unconditional logistic regression. In age-adjusted analyses, there were positive associations of prostate cancer (all stages combined) risk with total energy intake as well as intake of total fat (saturated and monounsaturated), protein, retinol and zinc. The positive association with energy intake was stronger for advanced cancer, with an excess risk of 70% for the highest quartile vs. the lowest. After adjustment for energy intake, there was no apparent association of prostate cancers (all stages combined) with any of the investigated nutrients. However, a weak positive association between intake of retinol and advanced cancer was observed. We conclude that our results provide some evidence that total energy intake is a risk factor for prostate cancer.

Adult↗

PubMed1996

A comparison of proliferation markers and their prognostic value for women with endometrial carcinoma. Ki-67, proliferating cell nuclear antigen, and flow cytometric S-phase fraction.

BACKGROUND: The understanding of proliferation is a central issue in oncology. Several methods exist for the assessment of the growth fraction and cell-cycle time, but comparative studies that give the clinician advice about the most reliable use of new markers are few. The aim of the current study was to perform methodologic, descriptive, comparative, and prognostic studies of Ki-67, proliferating cell nuclear antigen (PCNA), and flow cytometric S-phase fraction (SPF) in endometrial carcinoma. METHODS: The expression of Ki 67 (n = 175) and PCNA (n = 146) were studied immunohistochemically; and the SPF (n = 297) by flow cytometry. The median follow-up time was 78 months. RESULTS: Neither Ki-67 nor PCNA had any correlation to either the stage or the histopathologic subtype of the tumors, but they were covariant with the histopathologic grade (P < 0.05). There was an interrelationship between Ki-67 and PCNA (P < 0.001), and both were associated with the size of the SPF (P < 0.0001 and P < 0.05, respectively). Mean SPF was high in advanced stages and strongly associated with histopathologic subtype (P < 0.0001) and ploidy (P < 0.0001). Tumors with strong Ki-67 expression were more often aneuploid (P < 0.01). In initial analyses, Ki-67 and SPF were predictors of poor survival (P < 0.05 and P < 0.001, respectively), whereas PCNA was not. When SPF was added to a comprehensive multivariate model, Ki-67 provided no further prognostic information, whereas SPF remained a powerful predictor of survival. CONCLUSIONS: Ki-67 and, to a lesser extent, PCNA, give approximate estimates of the growth fraction, whereas SPF only reflects the proportion of cells in S-phase. However, SPF is by far the strongest predictor of survival.

Adult↗

PubMed1996

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

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

Adult↗

PubMed1996

A prospective study of smoking and risk of prostate cancer.

We evaluated the hypothesis that smoking increases the incidence of and mortality from prostate cancer. High-quality smoking information was collected in 1971-1975 in a nation-wide cohort of 135,006 male construction workers in Sweden. We achieved virtually complete follow-up through record linkages and ascertained as of December 1991 2,368 incident cases of prostate cancer and 709 deaths due to this disease. Rate ratios (RR) of prostate cancer incidence and mortality, with 95% confidence intervals (CI), were estimated in Poisson-based age-adjusted models, with amount and duration of smoking as independent variables. We found no convincing association between current smoking status, number of cigarettes smoked or years since onset and risk of prostatic cancer. The age-adjusted incidence RR among previous smokers was 1.09 and among current smokers 1.11 compared with non-smokers. Weak and inconsistent trends were seen with increasing number of cigarettes smoked per day and increasing duration among current smokers. Smokers of 15 or more cigarettes daily for at least 30 years experienced an incidence RR of 1.30. Mortality in ex-smokers was similar to that in never-smokers; it was, however, slightly increased among current smokers without any trend with amount smoked or duration. The weak and inconsistent associations between smoking and prostate cancer could easily have arisen due to bias or confounding. We therefore conclude that smoking is most likely not causally linked to the occurrence of prostate cancer.

Adult↗

PubMed1996

Trends in non-epithelial cancer incidence in Denmark, Finland, and Sweden, 1961-1990.

Trends in the incidence of non-epithelial cancers are particularly likely to reflect environmental carcinogens, since these malignancies are not commonly the targets of screening efforts, and have generally not been closely associated with life style factors such as cigarette smoking and diet. We used data from nation-wide cancer registries in Denmark, Finland, and Sweden to examine trends in non-epithelial cancers over the period 1961-1990. Linear regression analysis of age-standardized rates, and age-period-cohort models were fit to assess the temporal patterns within each country. Within each of the 3 countries, there was a similarly increasing incidence of both hematological malignancies and nervous system/bone/soft-tissue neoplasms. The increases were smallest in children and adolescents (ages 0-14), moderate among young and middle aged adults (ages 15-64), and most pronounced among the elderly (ages 65+). Age-period-cohort modeling suggested that the dominant factor in the increases were birth cohort effects. It is not clear what factors underlie this increase in incidence; it seems most likely that increases both in diagnostic efficiency and in exposure to environmental carcinogens play a role.

Adolescent↗

PubMed1996

Trends in prostate cancer survival in Sweden, 1960 through 1988: evidence of increasing diagnosis of nonlethal tumors.

BACKGROUND: The incidence of prostate cancer has increased during the past 30 years but has been paralleled by increases in survival rates from this disease, despite the absence of documented major improvement in curative treatment. Since a high prevalence of microscopic prostate cancer has been observed in autopsied men and because many prostate cancers may never surface clinically, increased diagnostic activities might have led to increased detection of less aggressive tumors. PURPOSE: This study was conducted to elucidate whether the trends in prostate cancer incidence and patient survival may be due to increasing diagnoses of nonlethal tumors. METHODS: We analyzed a population-based cohort comprising all cases of prostate cancer (n = 80,901) detected in Sweden during the period of 1960 through 1988. Five hundred eighteen patients (0.64% of the total number) who could not be followed because of emigration or an incomplete national registration number were excluded. Observed and relative survival rates were calculated for the entire cohort of 80,383 assessable patients per 5-year age group in 5-year periods of diagnosis and according to diagnostic method and were compared between geographic areas with differences in incidence rates. To estimate the independent effects of these determinants, multivariate analyses were performed. RESULTS: For the 80,383 patients with complete follow-up, the 10- and 20-year observed survival rates were 17.5% (95% confidence interval [CI] = 17.2%-17.9%) and 3.5% (95% CI = 3.2%-3.7%), and the relative survival rates were 41.1% (95% CI = 40.3%-41.9%) and 28.6% (95% CI = 26.5%-30.1%), respectively. Relative survival rates improved markedly over time; 10-year relative survival rates increased from 29% (95% CI = 27%-31%) among case patients diagnosed in 1960 through 1964 to 45% (95% CI = 43%-46%) among those diagnosed in 1975 through 1979. Relative survival rates leveled off after about 18 years at 18% (95% CI = 15%-20%) among patients diagnosed in 1960 through 1964 and at 31% (95% CI = 28%-34%) among those diagnosed in 1970 through 1974. An even more favorable outlook was observed in those case patients diagnosed later. In areas with a high or low incidence of prostate cancer, the 10-year relative survival rates were 45% (95% CI = 44%-47%) and 36% (95% CI = 34%-38%), respectively. In the early 1960s, the calculated loss of life expectancy after diagnosis varied from about 68% (95% CI = 61%-75%) of the expected length of life in the youngest age group to about 48% (95% CI = 46%-50%) in the oldest age group. From 1960 through 1964 to 1985 through 1988, the loss of life expectancy decreased by more than 50% in all age groups. The differences in relative survival rates between age groups were small, with a gradual decrease in age groups more than 60-64 years of age. CONCLUSIONS: Most of the great temporal improvement and geographic variation in survival rates are quantitatively consistent, with likely increases in the rate of detection of nonlethal tumors. IMPLICATIONS: The increase in relative survival rates must be taken into consideration when evaluating the outcome of treatment of prostate cancer, since nonrandomized comparisons may be confounded by time trends. Diagnosis of nonlethal tumors raises concerns because the individual would suffer from the psychologic burden of a cancer diagnosis without any therapeutic benefit.

Age Distribution↗

PubMed1996

The risk of stomach cancer in patients with gastric or duodenal ulcer disease.

BACKGROUND: Helicobacter pylori infection, now considered to be a cause of gastric cancer, is also strongly associated with gastric and duodenal ulcer disease. The discovery of these relations has brought the long-controversial connection between peptic ulcers and gastric cancer into focus. METHODS: We estimated the risk of stomach cancer in a large cohort of hospitalized patients with gastric or duodenal ulcers, as recorded in the Swedish Inpatient Register between 1965 and 1983. Altogether, 57,936 patients were followed through 1989, for an average of 9.1 years. The standardized incidence ratio--the ratio of the observed number of cancers to the number expected on the basis of the incidence in the Swedish population at large--was used as a measure of relative risk. RESULTS: After peaking in the first 3 years of follow-up, the standardized incidence ratio for gastric cancer among 29,287 patients with gastric ulcers leveled off at 1.8 (95 percent confidence interval, 1.6 to 2.0) and remained significantly increased throughout follow-up, which was as long as 24 years for some patients. Prepyloric ulcer, diagnosed in 8646 patients, was not associated with a significant excess risk (standardized incidence ratio, 1.2; 95 percent confidence interval, 0.8 to 1.6). In the cohort of patients with duodenal ulcers (24,456 patients), the incidence of gastric cancer was significantly lower than expected. After the second year of follow-up, the standardized incidence ratio was only 0.6 (95 percent confidence interval, 0.4 to 0.7) and remained stable thereafter. CONCLUSIONS: Gastric ulcer disease and gastric cancer have etiologic factors in common. A likely cause of both is atrophic gastritis induced by H. pylori. By contrast, there appear to be factors associated with duodenal ulcer disease that protect against gastric cancer.

Adult↗