Colorectal cancer: key points

• In Scotland, after non-melanoma skin cancer, lung cancer, and prostate cancer, colorectal cancer is the fourth most commonly diagnosed cancer in men, and the fourth most common in women after non-melanoma skin cancer, breast cancer, and lung cancer.  It is the second most common cause of death from cancer in men after lung cancer, and the third most common in women after lung and breast cancer.
• Currently, around 2,090 men and 1,740 women are diagnosed with colorectal cancer in Scotland every year.
• Excluding non-melanoma skin cancer, colorectal cancer accounts for just under 15% of all cancers diagnosed in men, and around 11.5% of all cancers diagnosed in women.
• Based on current rates of disease, an estimated 1 in 18 men, and 1 in 22 women develop colorectal cancer during their lifetime.
• Between 1999 and 2009, the age-standardised mortality rate of colorectal cancer decreased by an estimated 19.5% in men, and 14.3% in women. 
• The incidence of colorectal cancer is higher in Scotland than England.  The incidence rates for Scotland fall within the mid-upper range of rates for other countries that have data available for comparison. 
• The main risk factors for colorectal cancer are dietary (vegetables and fibre are probably protective, red meat may increase risk), obesity, lack of physical activity, genetic factors, and (probably) long-term smoking.
• Randomised controlled trials carried out in Minnesota, USA; Funen, Denmark; and Nottingham, UK, have shown that it is possible to reduce mortality from colorectal cancer by screening based on faecal occult blood testing (FOBt). Pilot studies carried out in Grampian, Tayside, and Fife, and in parts of West Midlands have demonstrated that screening with FOBt is feasible in the UK, and that it should reduce deaths from colorectal cancer.  The Scottish Bowel Screening Programme is now a national programme, since December 2009.
• Survival from colorectal cancer has increased substantially over the last 30 years. For both men and women, the relative survival at five years increased from around 36% for patients diagnosed during 1980-84 to 55% for those diagnosed during 2003-2007.
• There are no substantial differences in incidence of or mortality from colorectal cancer between socioeconomic categories, but survival is significantly lower among people living in areas of socioeconomic deprivation.
• Although there is no recent evidence of any health boards in Scotland having worse survival from colorectal cancer than the average for Scotland, previous audits and international comparisons have suggested possible scope for improving outcomes from colorectal cancer in Scotland. 

Key statistics:

Notes:
(1) Number of colorectal cancer survivors at 31 Dec 2007 who had been diagnosed in the previous 20 years per 100,000  population.
(2) Five year relative survival for patients diagnosed during the period 2003-2007 (not standardised).