Mary Henry (Independent)

I thank the Minister of State for attending the House this evening.

The issue of colorectal cancer was drawn to my attention by Colm Ó Móráin, professor of medicine at Trinity College Dublin and senior gastroenterologist in the Adelaide and Meath Hospital at Tallaght. Colorectal cancer poses a major public health problem. According to a recent report from the United European Gastroenterology Federation, it is the leading cause of morbidity and deaths from cancer in Europe. The incidence of colorectal cancer is steadily increasing in both males and females, and that increase is most prominent for malignancies in the sigmoid colon. In Ireland, 1,730 patients with colorectal tumours are diagnosed each year, with 925 deaths occurring.

The prognosis for patients with colorectal cancer is closely related to the clinical and pathological stage of the disease at the time of diagnosis. Unfortunately, most cases of colorectal cancer are detected at an advanced stage, and survival rates are therefore poor. Five years' survival for cancer limited to the bowel wall at the time of diagnosis approaches 90%. However, survival of five years is 35% to 60% when regional lymph nodes are involved, and less than 10% with more extensive metastatic disease. That makes it the most common cause of cancer mortality in western Europe.

The biology of colorectal cancer provides an excellent opportunity for early detection. It develops as a result of stepwise accumulation of genetic mutations. The transformation from normal mucosa to adenoma and ultimately to carcinoma appears to occur slowly over about ten to 20 years. Survival is closely related to the clinical and pathological stage of the disease diagnosis. Evidence from several studies suggests that detection and consecutive removal of pre-cancerous lesions by endoscopic polypectomy reduces the incidence of death.

Cost-effectiveness analyses have shown that screening for colorectal cancer, even in the context of imperfect compliance, significantly reduces mortality, with costs lower than or comparable with already implemented cancer-screening procedures, such as those for breast cancer. However, screening tests vary considerably in diagnostic performance, compliance rates, acceptability and cost. Randomised controls, however, in Europe and the USA have shown a decrease in death rates of between 15% and 30%.

One test widely used, which would cost less than €10,000 per life saved, as compared with €200,000 per individual for chemotherapeutic drugs, is the faecal occult blood test. Such tests detect the presence of blood or blood products in the stool. They rely on the fact that colorectal neoplasms tend to bleed more often than normal mucosa. Since some colorectal neoplasms will bleed only intermittently, testing several stool samples increases the yield. It has become standard to test three consecutive stools using guaic-based methods. Such tests have the disadvantage that they may react positively to peroxidases activity in the faeces and not solely to peroxidases activity from human haem. Faecal occult blood can also be traced using immunochemical methods. However, they are more expensive and have been criticised because of their low sensitivity.

Recently performed trials indicate that screening targeted at particular age groups significantly reduces colorectal cancer mortality. Consequently, various professional organisations have recommended the screening of asymptomatic persons to reduce the mortality rate in the population. As I said, in several European countries such screening has either been introduced or is being considered. The European Union has recommended faecal occult blood screening for colorectal cancer in men and women aged 50 to 74. It would appear to be cost-effective, and the optimum strategy cannot be determined solely by the currently available data. We must have considerable research into this area to determine the most important screening strategy. However, no such studies are in progress in Ireland. This proposal defines the start of an endeavour that will garner significant information on many aspects of screening programmes for colorectal cancer in Ireland.

Making the screening programme a reality and achieving high response and compliance rates are important. The pitfalls of earlier screening programmes should be avoided. Co-operation with existing screening programmes such as the breast-screening programme that I mentioned can greatly contribute to avoiding the pitfalls and stimulate progress in implementing a screening programme for colorectal cancer. The practicality of a screening programme depends on the detection method. Fortunately, faecal occult blood testing is simple and can be performed by the subjects at their homes without high demand.

It is essential to know those who are at risk and to be familiar with their specific education and information needs if we are to achieve high awareness of colorectal cancer and, in turn, a high level of acceptance and response to screening among clients. It is particularly important for scientific and practical reasons that we give sufficient and accurate information to all relevant and interested parties, especially if we wish to maintain and improve high rates of response and compliance.

I am sure the Minister of State will be alarmed to hear that the level of awareness in Ireland of the risks and symptoms of colorectal cancer is among the lowest in the European Union. It is conceivable that those who consider themselves to have a high risk of developing colorectal cancer are more inclined to respond and to be compliant. A high-risk assessment questionnaire has been developed to assess such expectations and considerations. Other considerations, such as general quality of life and satisfaction, might influence levels of response and compliance.

Are people satisfied to undergo regular colorectal cancer screening without a guarantee that they will be free of the cancer for life? It is possible that the awareness of risk influences the quality of one's life. Changes in one's quality of life and behaviour can change one's response to screening tests in many ways. It is hard to predict whether the availability of screening will be seen as positive or negative for certain people. We need to examine and address such issues.

I have details of how it is proposed to conduct such a pilot project and I would be delighted to submit them to the Minister of State. I hope he will mention in his response that he supports the implementation of a pilot project, especially as it is such an important issue in this country, where there is a low level of awareness of the high incidence of colorectal cancer.