Original PaperThe prognostic role of gender in survival of adult cancer patients
Introduction
Life expectancy for women at birth exceeds that for men in almost all countries, exceptions being Bangladesh, Bhutan, India, Nepal and Pakistan; the anomaly of these countries generally being considered as an effect of strong discrimination against women[1]. In most industrialised countries, the greater life expectancy of women has been known for a long time[2]. In Sweden, the country with the longest reliable mortality statistics, female life expectation at birth has exceeded males since 1751 when data became available[1]. Some researchers predict that the gender gap will increase in the near future[3], whilst others suggest it will decrease slightly[4]. One view of the phenomenon is that it is biological and approaches the status of a law of nature. However, even if women do have an advantage over men in terms of psychological and biological robustness[2], the causes of this difference remain poorly understood.
The potential effect of gender as a predictor of life expectancy of cancer patients has not been sufficiently investigated. EUROCARE I, a project for estimating the survival of European cancer patients diagnosed during 1978–1985[5]and other studies found that female gender is a favourable prognostic factor for survival, even after adjusting for competing mortality (i.e. when relative survival were considered) and age6, 7, 8, 9.
The aim of the present study was to evaluate gender differences in cancer survival in a large set of data collected across 45 population-based cancer registries in 17 European countries (EUROCARE II). By analysing such a large set of survival data, undesirable random effects will be reduced, facilitating identification of the potential prognostic role of gender after adjusting for competing mortality, age, geographical area and cancer site.
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Patients and methods
Survival analysis was carried out on 1 188 469 malignant cancer adult patients (ICD9: 140–208 except 173) diagnosed from 1985 to 1989 in 17 European populations participating in EUROCARE II. Cases discovered at autopsy, first diagnosed with another malignant tumour or known on the basis of death certificates only (DCO) were not included. Cases were followed for a minimum of 5 years after diagnosis. Some registries (Denmark, Estonia, Finland, Slovakia, Slovenia and Iceland) cover the population of
Life expectancy
In all countries participating in the EUROCARE II study, life expectancy at birth was higher for women than for men according to WHO 1992 data (Fig. 1)[11]. Differences between the sexes ranged from around 4 years in Iceland, where the expectation of life for men was 76.8 years, to 11.2 years in Estonia, where the expectation of life for men was 63.6 years (Table 1). The three highest differences were observed in the Eastern European countries Estonia, Poland and Slovakia; whereas the three
Discussion
Women generally have a much longer life expectancy than men. Several earlier observations suggested that this female advantage is present in cancer patients, even after adjusting for competing mortality5, 6, 9. The purpose of the present study was to evaluate the role of gender as a potential predictor of survival in cancer patients, making use of the very large population-based data-set of the EUROCARE II. To our knowledge, this is the first time that gender has been analysed as predictor of
Acknowledgements
The EUROCARE study was financed through the BIOMED programme of the European Union.
References (25)
The concept of illness behaviour
J Chron Dis
(1962)- et al.
A new method of classifying prognostic co-morbidity in longitudinal studies: development and validation
J Chron Dis
(1987) The sex differences in illness incidence, prognosis, and mortality: issues and evidence
Soc Sci Med
(1983)Why do women live longer than men?
Soc Sci Med
(1976)Women’s longevity
Science
(1995)Why do women live longer then men?
Science
(1987)- et al.
Modelling and forecasting US sex differentials in mortality
Int J Forecasting
(1991) - Bell FC, Wade AH, Goss SC. Life tables for the United States Social Security Area 1900–2080. 1992. Actuarial Study No....
- Berrino F, Sant M, Verdecchia A, Capocaccia R, Hakulinen T, Esteve J, eds. Survival of Cancer Patients in Europe, The...
- et al.
The effect of female sex hormone on cancer survival
JAMA
(1990)
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The EUROCARE Working Group for this study is listed in the Appendix A.