Overdiagnosis and overtreatment of breast cancer: Overdiagnosis and overtreatment in service screening

Screening mammography has been shown to be effective for reducing breast cancer mortality. According to screening theory, the first expected consequence of mammography screening is the detection of the disease at earlier stages and this diagnostic anticipation changes the population incidence curve, with an observed increase in incidence rates at earlier ages. It is unreasonable to expect that the age-specific incidence will ever return to pre-screening levels or to anticipate a significant reduction of incidence at older ages immediately after the first screening round. The interpretation of incidence trends, especially in the short term, is difficult. Methodology for quantification of overdiagnosis and statistical modelling based on service screening data is not well developed and few population-based studies are available. The overtreatment issue is discussed in terms of appropriateness of effective treatment considering the question of chemotherapy in very early stages and the use of breast conserving surgery

Estimate of overdiagnosis of breast cancer due to mammography after adjustment for lead time. A service screening study in Italy

INTRODUCTION: Excess of incidence rates is the expected consequence of service screening. The aim of this paper is to estimate the quota attributable to overdiagnosis in the breast cancer screening programmes in Northern and Central Italy. METHODS: All patients with breast cancer diagnosed between 50 and 74 years who were resident in screening areas in the six years before and five years after the start of the screening programme were included. We calculated a corrected-for-lead-time number of observed cases for each calendar year. The number of observed incident cases was reduced by the number of screen-detected cases in that year and incremented by the estimated number of screen-detected cases that would have arisen clinically in that year. RESULTS: In total we included 13,519 and 13,999 breast cancer cases diagnosed in the pre-screening and screening years, respectively. In total, the excess ratio of observed to predicted in situ and invasive cases was 36.2%. After correction for lead time the excess ratio was 4.6% (95% confidence interval 2 to 7%) and for invasive cases only it was 3.2% (95% confidence interval 1 to 6%). CONCLUSION: The remaining excess of cancers after individual correction for lead time was lower than 5%

Lower incidence rates but thicker melanomas in Eastern Europe before 1992: A comparison with Western Europe

The objective of this study was to investigate the epidemiology of melanoma across Europe with regard to Breslow thickness and body-site distribution. Incidence data from Cancer Incidence in 5 Continents and the EUROCARE-melanoma database were used: 28 117 melanoma cases from 20 cancer registries in 12 European countries, diagnosed between 1978 and 1992. Regression analysis and general linear modelling were used to analyse the data. Melanomas in Eastern Europe were on average 1.4 mm thicker (P<0.05) than in Western Europe and appeared more often on the trunk. From 1978 to 1992, their Breslow thickness had decreased in Western but not Eastern Europe. There was a latitude gradient in incidence, with highest rates in southern regions in Eastern Europe and an inverse gradient in Western Europe, with highest rates in the North. Mortality:incidence ratios were less favourable in southern parts across Europe, especially in Eastern Europe. If Eastern European populations copy the sunbathing behaviour of the West it is likely that in the near future a higher melanoma incidence can be expected there

European code against cancer 4th edition: 12 ways to reduce your cancer risk

This overview describes the principles of the 4th edition of the European Code against Cancer and provides an introduction to the 12 recommendations to reduce cancer risk. Among the 504.6 million inhabitants of the member states of the European Union (EU28), there are annually 2.64 million new cancer cases and 1.28 million deaths from cancer. It is estimated that this cancer burden could be reduced by up to one half if scientific knowledge on causes of cancer could be translated into successful prevention. The Code is a preventive tool aimed to reduce the cancer burden by informing people how to avoid or reduce carcinogenic exposures, adopt behaviours to reduce the cancer risk, or to participate in organised intervention programmes. The Code should also form a base to guide national health policies in cancer prevention. The 12 recommendations are: not smoking or using other tobacco products; avoiding second-hand smoke; being a healthy body weight; encouraging physical activity; having a healthy diet; limiting alcohol consumption, with not drinking alcohol being better for cancer prevention; avoiding too much exposure to ultraviolet radiation; avoiding cancer-causing agents at the workplace; reducing exposure to high levels of radon; encouraging breastfeeding; limiting the use of hormone replacement therapy; participating in organised vaccination programmes against hepatitis B for newborns and human papillomavirus for girls; and participating in organised screening programmes for bowel cancer, breast cancer, and cervical cancer