Colonoscopy is an important method for diagnosing bowel cancer but it is also an uncomfortable, invasive procedure which patients would happily rather do without. A Dublin-based research group is working on an alternative which is completely non-invasive.
It is known as "virtual colonoscopy" and is based on the use of computer power and CT X-ray scans. The work is one of the projects funded under the Irish Cancer Society's research programme, paid for in part by the generous contributions made by the public.
The society has almost £400,000 to invest in advanced medical research this year and it recently announced support for 19 projects here, five new and 14 ongoing. Another £75,000 will be given to the Irish Clinical Oncology Research Group which seeks to get the latest drug treatments quickly into clinical use.
Colon cancer is a major problem in Ireland with 1,800 new cases and 950 deaths each year from the disease. Yet it can be prevented if diagnosed early.
The research on the new diagnostic technique is being done by Dr Padraic MacMathuna, consultant gastroenterologist at the Mater Hospital, Dublin, and by Dr Paul Whelan, of DCU's Vision Systems Laboratory. It is based on pioneering research by Dr Helen Fenlon, who first demonstrated the potential of virtual colonoscopy (VC) in diagnosing cancer.
The approach involves producing computer-generated, three-dimensional images of the colon from two dimensional CT scans. The original CT data is analysed and reprocessed by the computer system which then gives a 3-D virtual representation of the interior of the colon.
The object is to be able to detect polyps, tiny pre-malignant growths. The system is designed to identify the polyps automatically, giving doctors locations for further investigation. It represents an important screening technique which helps reduce unnecessary testing.
"Conventional colonoscopy procedures require sedation, can be uncomfortable and possible give rise to complications," said Dr MacMathuna. "VC is not invasive. Rather it provides accurate computer-generated, 3-D images of the colon from original CT scans."
Clinical trials of the technique have begun and will involve about 250 people over the next 12 to 24 months. "We will be comparing outcomes from traditional techniques with our new technology. Preliminary results are encouraging and the ultimate aim is to perfect the precision of VC in picking up tiny pre-malignant growths."
The approach may be of particular significance for high-risk individuals: those with a family history of colon cancer. It should make diagnosis less arduous and also help reduce illness and possibly death through early detection.