Current trends in colorectal cancer: site, incidence, mortality and survival in England and Wales.

The objective was to examine trends in colorectal cancer (CRC) incidence and mortality in England and Wales over the last 30 years. Age-standardized incidence, mortality and survival rates for CRC, based on data from the National Cancer Intelligence Centre at the Office for National Statistics, were calculated and trends assessed. Between 1971 and 1997 the total number of cases of CRC increased by 42%, from 20,400 to 28,900. The site distribution of CRC between 1971 and 1994 was: rectum 38%, sigmoid 29%, caecum 15%, transverse colon and flexures 10%, ascending colon 5%, and descending colon 3%. Between 1971 and 1997 the direct age-standardized incidence increased by 20% in males and by 5% in females. The direct age-standardized mortality fell by 24% in males and by 37% in females. Age-standardized relative 5-year survival in adults improved from 22%-27% for patients diagnosed during 1971-1975 to over 40% for those diagnosed during the period 1991-1993. In conclusion, the incidence of CRC in England and Wales has been steadily rising. It is more common in males and has increased more rapidly in males than in females. The reasons for these trends remain unclear. Five-year survival has improved substantially, but rates are still below those in comparable countries elsewhere in Europe and in the USA.