Approved research

Optimisation of colorectal cancer prevention strategies by identification of risk factors for proximal colon cancer.

Lay summary

Colorectal cancer, also known as bowel cancer, is the third most commonly diagnosed cancer, with a reported 1,849,518 new cases, and the second most common cause of cancer death, with 880,792 deaths worldwide in 2018 (1). These cancers occur along the length of the bowel, with the number of new cases of those occurring in the upper part, farthest away from the rectum, increasing globally (2, 3). Most bowel cancers start as polyps, which are small growths found on the wall of the bowel. Bowel cancer screening aims to check the inner wall surface for any polyps or abnormalities that could develop into cancer and has been shown to reduce the number of newly diagnosed cases. Unfortunately, the current screening tests are less effective at identifying cancers in the upper part of the bowel; and as a result, these cancers are often diagnosed at a later stage, lowering patients' chances of survival (5). This highlights the importance of research to identify risk factors for these cancers so that we can prevent them from occurring. Research has shown that certain factors, including diet, lifestyle and the use of common drugs such as aspirin can affect the risk of developing bowel cancer (8, 9). However, it is unclear whether these risk factors have an effect on cancers in all parts of the bowel. This study aims to identify factors including diet, lifestyle and common drugs, which increase or decrease the likelihood of cancer developing in the upper part of the bowel specifically. The large size of the UK-BIOBANK cohort and the number of cancer cases accumulated over the years of follow-up will allow for in-depth analyses to be performed. This project will be conducted over the course of 24 months and will support existing research into risk factors for bowel cancer. Study results can be used to develop strategies and guidelines to help prevent the number of newly diagnosed cases of bowel cancer each year, particularly those found in the upper part of the bowel, which are harder to detect by screening.