Trends in the survival of patients diagnosed with cancers in the respiratory system in the Nordic countries 1964–2003 followed up to the end of 2006

BACKGROUND: Previous studies have shown that there have been systematic differences between the Nordic countries in population-based relative survival of patients with respiratory cancer (lung, pleura, larynx, nose and sinuses). MATERIAL AND METHODS: Relative survival of patients with respiratory cancer diagnosed in the Nordic countries in 1964-2003 and followed up to the end of 2006 was studied and contrasted with developments in incidence and mortality. RESULTS: For cancer of the lung, relative survival is lower in Danish patients than in the other countries during the first months of follow-up after diagnosis. For cancer of pleura, the relative survival ratios indicate that there may be problems in the official coding of the causes of death in Denmark, Norway and Sweden. There has been little improvement in survival of patients with cancer of the respiratory organs in the Nordic countries over time. CONCLUSIONS: The slightly lower survival of Danish lung cancer patients may be related to a less favourable stage distribution and to an increased prevalence of causal factors, affecting the mortality due to competing risks of death. A reclassification of official causes of death at the cancer registry may be needed for cancer of the pleura in order to make the corresponding mortality rates comparable between countries.