RESUMEN
Large-scale epidemiologic studies have consistently demonstrated the effectiveness of mammographic screening programs, however the benefits are still subject to debate. We estimated the effect of the Dutch screening program on breast cancer mortality. In a large multi-region case-referent study, we identified all breast cancer deaths in 2004 and 2005 in women aged 50-75 who had been invited for screening (cases). Cases were individually matched to referents from the population invited to screening. Conditional logistic regression was used to estimate the odds ratio (OR) of breast cancer death according to individual screening history. The OR was adjusted for self-selection bias using regional correction factors for the difference in baseline risk for breast cancer death between screened and unscreened women. A total of 1233 cases and 2090 referents were included in this study. We found a 58% reduction in breast cancer mortality in screened versus unscreened women (adjusted OR = 0.42, 95% CI 0.33-0.53). Screening, i.e. early detection and treatment, has resulted in a substantial reduction in breast cancer mortality, indicating that the Dutch breast cancer screening program is highly effective.
Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/mortalidad , Detección Precoz del Cáncer/mortalidad , Mamografía , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Persona de Mediana EdadRESUMEN
OBJECTIVE: We designed a case-referent study to investigate the effect of mammographic screening at the individual level, looking at the association of breast cancer death with screening history. METHODS: The study population included all women aged 50-75 in the province of Limburg, the Netherlands who had been invited to the screening program from 1989 to 2006. From this population, 118 cases originated who died of breast cancer in 2004 or 2005. The screening history of these cases was collected and compared with a sample of the invited population. The breast cancer death rate in the screened relative to the unscreened women was estimated as the odds ratio (OR). This OR was adjusted for self-selection bias, the difference in baseline risk for breast cancer death between screened and unscreened women. RESULTS: Analysis of the data showed a breast cancer mortality reduction of 70% in the screened versus the unscreened women (OR = 0.30, 95% CI 0.14-0.63). The magnitude of self-selection was estimated specifically for Limburg. After correction for self-selection bias, the effect of screening increased to 76% (OR = 0.24, 95% CI 0.10-0.58). CONCLUSION: Screening resulted in a remarkable reduction in breast cancer mortality. Contrary to findings in other countries, adjustment for self-selection in Limburg had no influence on the impact of screening. Thanks to a well-organized centralized screening program, similar results are expected in other regions of the Netherlands.
Asunto(s)
Neoplasias de la Mama/mortalidad , Anciano , Neoplasias de la Mama/diagnóstico , Estudios de Casos y Controles , Femenino , Humanos , Mamografía , Tamizaje Masivo , Persona de Mediana Edad , Países Bajos/epidemiología , Oportunidad Relativa , Sesgo de SelecciónRESUMEN
OBJECTIVE: Time trend studies in the USA have shown that the incidences of adenocarcinomas of the oesophagus and gastric cardia have risen strongly since the 1970s, whereas the incidence of squamous cell carcinomas of the oesophagus has declined. Earlier, we found that the incidence of these adenocarcinomas also rose in some European countries until the early 1990s. The main goal of this study was to investigate more recent trends in the incidence of oesophageal and stomach cancer subtypes in the European countries. METHODS: Eurocim cancer incidence data of 23 cancer registries from 13 European countries were used to investigate the incidence trends in oesophageal and stomach cancer subtypes during the 1983-1997 period. We calculated estimated annual percentage changes (EAPCs) in European age-standardized incidence rates and 95% confidence intervals. RESULTS: The incidence of adenocarcinomas of the oesophagus and gastric cardia rose in most, but not all, registration areas (EAPCs were usually 1-7%), the strongest in the UK and Ireland. Oesophageal squamous cell carcinoma incidence rose mostly in Northern European and Slovakian men (EAPCs: 1-5%) and in women from all regions (EAPCs: 1-8%), but declined mostly in Southern and Western European men (EAPCs: -1 to -5%). CONCLUSION: Our results are partly in line with earlier findings on adenocarcinomas of the oesophagus and gastric cardia. There was, however, substantial heterogeneity in trends of subtypes of these cancers within Europe. There may be different risk factors for these cancers, and the prevalence of these risk factors may differ among countries.
Asunto(s)
Adenocarcinoma/epidemiología , Neoplasias Esofágicas/epidemiología , Neoplasias de Células Escamosas/epidemiología , Neoplasias Gástricas/epidemiología , Europa (Continente)/epidemiología , Femenino , Humanos , Incidencia , Masculino , Sistema de Registros/estadística & datos numéricosRESUMEN
The prevalence of risk factors for endometrial and ovarian cancer, such as obesity, oral contraceptive use and parity has changed among Dutch women. Therefore, trends in age-specific incidence and mortality from endometrial and ovarian cancer were studied between 1986 and 2003 in the region of the Maastricht Cancer Registry. Trends were standardized to the European population and were examined by the estimated annual percentage change (EAPC). The overall incidence and mortality from endometrial cancer increased in the period 1993-2003 by 3.4% (P=0.03) and 4.0% (P=0.04), respectively. The increasing incidence trend was observed in stages II and III tumours. Overall incidence trends of ovarian cancer declined after 1992 by 2.6% (P=0.03) and overall mortality after 1991 by 1.7% (P=0.04). The increasing prevalence of obesity might explain the increasing trends in endometrial cancer. Parity and increased oral contraceptive use could possibly explain the decline in ovarian cancer.
Asunto(s)
Carcinoma Endometrioide/epidemiología , Carcinoma Endometrioide/mortalidad , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/mortalidad , Neoplasias Uterinas/epidemiología , Neoplasias Uterinas/mortalidad , Adenocarcinoma/epidemiología , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Anciano , Carcinoma Endometrioide/patología , Femenino , Predicción , Humanos , Incidencia , Persona de Mediana Edad , Estadificación de Neoplasias , Países Bajos/epidemiología , Neoplasias Ováricas/patología , Sistema de Registros , Análisis de Supervivencia , Neoplasias Uterinas/patologíaRESUMEN
OBJECTIVE: Many case-control studies have reported that salt and cured meat intake are positively, and refrigerator use is inversely, associated with stomach cancer risk. In the current prospective study these associations were evaluated. METHODS: The Netherlands Cohort Study consisted of 120,852 men and women ages 55-69 years at baseline in 1986. Salt exposure was measured by calculating mean daily sodium intake (dietary salt) from 150 food items and by specific salt questions. After 6.3 years of follow-up, 282 incident stomach cancer cases were available for analyses. Case-cohort analyses were based on the 282 cases and 3123 subcohort members. RESULTS: In multivariate analyses adjusted for age, sex, smoking, education, stomach disorders, history of stomach cancer in the family, rate ratios (RR) for increasing quintiles of energy-adjusted intake of dietary salt were 1.00, 1.49, 1.03, 1.54 and 1.18, respectively (p trend = 0.43). An inverse association was found between stomach cancer and salt added at the hot meal (p trend = 0.04). For salt added to home-made soup, use of salt at the table, salt preference and duration of refrigerator use, no associations were observed. Positive associations were found for bacon (RR highest/lowest intake = 1.33; 95% CI = 1.03-1.71) and other sliced cold meat (RR highest/lowest intake = 1.29; 95% CI = 0.96-1.72), but not for smoked sausage, total cold meats, rashers/bacon, boiled ham and smoked beef/pork loin roll. Separate analyses among subjects with self-reported stomach disorders revealed higher RR of stomach cancer for dietary salt and several types of cured meat. CONCLUSION: The present findings suggest that intake of dietary salt and several types of cured meat were weakly positively associated with stomach cancer risk.