National comparisons of lung cancer survival in England, Norway and Sweden 2001e2004: differences occur early in follow-up Lars Holmberg, 1 Fredrik Sandin, 2 Freddie Bray, 4 Mike Richards, 5 James Spicer, 1 Mats Lambe, 3 A ˚ sa Klint, 6 Mick Peake, 7 Trond-Eirik Strand, 4 Karen Linklater, 1 David Robinson, 1 Henrik Møller 1 ABSTRACT Background Countries with a similar expenditure on healthcare within Europe exhibit differences in lung cancer survival. Survival in lung cancer was studied in 2001e2004 in England, Norway and Sweden. Methods Nationwide cancer registries in England, Norway and Sweden were used to identify 250 828 patients with lung cancer from England, 18 386 from Norway and 24 886 from Sweden diagnosed between 1996 and 2004, after exclusion of patients registered through death certificate only or with missing, zero or negative survival times. 5-Year relative survival was calculated by application of the period approach. The excess mortality between the countries was compared using a Poisson regression model. Results In all subcategories of age, sex and follow-up period, the 5-year survival was lower in England than in Norway and Sweden. The age-standardised survival estimates were 6.5%, 9.3% and 11.3% for men and 8.4%, 13.5% and 15.9% for women in the respective countries in 2001e2004. The difference in excess risk of dying between the countries was predominantly confined to the first year of follow-up. The relative excess risk ratio during the first 3 months of follow-up comparing England with Norway 2001e2004 varied between 1.23 and 1.46, depending on sex and age, and between 1.56 and 1.91 comparing England with Sweden. Conclusion Access to healthcare and population awareness are likely to be major reasons for the differences, but it cannot be excluded that diagnostic and therapeutic activity play a role. Future improvements in lung cancer management may be seen early in follow-up. INTRODUCTION Despite increasing overall cancer survival and diminishing regional differences within Europe, there are still differences between countries with similar national healthcare systems and total national expenditure on healthcare. 1 2 Survival differences are generally most pronounced for cancers with good survival, indicating that these differences may be sensitive to the allocation of health resources. Differences are less pronounced for those cancers with a good prognosis which are treated at specialised centres (eg, testicular cancer) and for cancers with a poor prognosis (eg, lung cancer). 13 An understanding of the differences in survival on a population level, even for cancers with a poor prognosis, may reveal critical points in the infrastructure of healthcare that are important areas for improvement. Unless detected at a localised and resectable stage, lung cancer is a rapidly fatal disease and the effective therapeutic arsenal is limited. EUROCARE 4 reported a 5-year relative survival for the follow- up period 2000e2002 of 8.4% in the UK, 11.2% in Norway and 13.9% in Sweden. 2 Between 1990 and 1994, and 2000 and 2002 there was a relative improvement in survival of 20e35% in Norway and Sweden, but <10% in the UK. 2 We studied patterns of relative survival during 2001e2004 in patients with lung cancer diagnosed in 1996e2004 in England, Norway and Sweden. These three countries have a similar expenditure on healthcare, and all have population-based cancer registration systems. We were particularly inter- ested in identifying the periods of follow-up where the major differences in survival between the countries occur, and in studying the impact on survival of age at diagnosis. METHODS Cancer registration in England Data are collected by eight regional cancer regis- tries. 4 5 The means of collecting the data vary between registries, from largely automated systems based on electronic pathology and hospital activity records, to manual operations where extraction of information from clinical records plays a large part. Electronic data sources are being increasingly used. The regional data are collated into a national data repository maintained by the Office for National Statistics and the National Cancer Intelligence Network. 6 These processes resolve cross-registry duplicates and provide continuous update of the vital status and cause of death for each person. Data linkage is achieved via the National Health Service (NHS) number, which is a unique person- level identifier for all English citizens registered with a general practitioner in the NHS. Cancer registration in Norway The Cancer Registry of Norway collects notifica- tions on cancer in the Norwegian population. Hospitals, pathological laboratories, general practi- tioners and the National Statistics Office (Statistics Norway) are the primary sources, with clinical notifications reported on structured templates and pathology notifications routinely sent to the Registry. Statistics Norway provides information 1 Division of Cancer Studies, King’s College London, School of Medicine, London, UK 2 Regional Oncological Centre, Uppsala/O ¨ rebro Region, Uppsala, Sweden 3 Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden 4 Norwegian Cancer Registry, Oslo, Norway 5 Department of Palliative Medicine, St Thomas’ Hospital, London, UK 6 Swedish Cancer Registry, National Board of Health and Welfare, Stockholm, Sweden 7 Department of Respiratory Medicine, Glenfield Hospital, Leicester, UK Correspondence to Professor Lars Holmberg, Division of Cancer Studies, King’s College London, School of Medicine, Research Oncology, 3rd Floor Bermondsey Wing, Guy’s Hospital, London SE1 9RT, UK; lars.holmberg@kcl.ac.uk Received 24 July 2009 Accepted 16 February 2010 436 Thorax 2010;65:436e441. doi:10.1136/thx.2009.124222 Lung cancer on January 21, 2022 by guest. 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