Population-based study of short- and long-term survival from colorectal cancer in Denmark, 1977–1999

BACKGROUND: Survival rates for patients with colorectal cancer have been lower in Denmark than in other European countries. The aim of this study was to examine temporal trends in relative survival from colorectal cancer between 1977 and 1999. METHODS: All patients diagnosed with colorectal cancer between 1977 and 1999 were identified using the nationwide population-based Danish Cancer Registry. Patients were linked with the Danish Central Population Registry to obtain data on survival to December 2002, and to select ten population controls per patient. RESULTS: A total of 69 562 patients with colorectal cancer were identified, of whom 49.2 per cent were men. Six-month relative survival after diagnosis increased from 69.7 per cent in 1977-1982 to 77.7 per cent in 1995-1999. Five-year relative survival rates increased from 37.8 to 46.8 per cent respectively. Women had slightly higher 5-year relative survival than men throughout the study period. Rectal tumours were associated with better survival than colonic tumours until 2 years after diagnosis, after which tumour location had no impact on survival. CONCLUSION: Relative survival of patients with colorectal cancer has improved in Denmark between 1977 and 1999, most probably reflecting better management of the disease.