Prospects for cancer control: colorectal cancer.

AIMS: The study assessed the contribution to the control of colorectal cancer achievable from primary prevention, screening, early diagnosis, and treatment in New Zealand.

METHODS

Available estimates of the attributable risk or protection offered by significantly increasing consumption of fruit and vegetables were used to predict the number of cases of (and deaths from) colorectal cancer prevented if these activities were effective in 1999. The potential effect of screening was also estimated from published results. Estimates of the potential effect of improvements in early diagnosis and treatment available from cancer-control plans of other countries were used to estimate the likely impact of such improvements in New Zealand.

RESULTS

Primary prevention could potentially prevent 81 deaths in men and 77 deaths in women from colorectal cancer each year. The potential impact of screening differed between screening methods, with the prevention of 44 deaths in men and 35 deaths in women from colorectal cancer by screening using faecal occult blood testing or 73 deaths in men and 53 deaths in women annually from colorectal cancer by screening using flexible sigmoidoscopy. Improvements in surgical practice and reorganisation of surgical services together with improved use of radiotherapy and chemotherapy could prevent about 82 deaths in men and 78 deaths in women from colorectal cancer each year.

CONCLUSIONS

The most immediate control of colorectal cancer appeared to be achievable by improvements in surgical services and the introduction of screening while increased consumption of fruit and vegetables provided potential longer-term reductions in colorectal cancer incidence and mortality.