Building a Database for Cancer Prevention: Keeping the Science Current
The Continuous Update Project
The largest ongoing review of cancer prevention and survival research of its kind in the world, AICR/WCRF's Continuous Update Project (CUP), has published its first progress report, providing an overview of the most active areas of research on food, nutrition, physical activity, weight and cancer.
The CUP maintains the world's largest scientific database on food, nutrition, physical activity, weight and cancer. The innovative project builds on AICR/WCRF's second expert report, published in 2007, which represented the most extensive analysis of the existing science at that time. With research burgeoning in the field of lifestyle and cancer prevention, the WCRF global network – which AICR is part of – wanted to make sure the recommendations reflect current science.
"The database is a unique resource and is essential for us to continually update the science," Rachel Thompson, PhD, the Deputy Head of Science for WCRF who has overseen the development of the CUP from its beginnings. The continuous stream of new studies means "we need a resource that we can add new evidence to as it is published. So once the data from a research paper is added to the database it can be included in any analysis we chose either today or in the future."
How the CUP works
The CUP focuses on systematically collecting, analyzing and reviewing the information for each cancer site. A panel of experts selected which cancer sites to first review based on whether there was a high amount of research and/or emerging research that would help fill knowledge gaps identified by the expert report. (Breast cancer survivorship was one of those gaps the CUP is currently undertaking.) The process follows the same rigorous methods as the previous expert report, with an independent team of scientists systemically adding relevant studies to a central database and a separate panel of international experts in the field reviewing the evidence and drawing conclusions.
The methodology also stays the same, with a set protocol for what studies to collect for each cancer site, says Teresa Norat, PhD, Principal Research Fellow at Imperial College, London, and the leader of the team of scientists conducting the ongoing systematic literature review. Once every month for each cancer site already begun, Dr. Norat and her team search online for all published prospective studies and clinical trials that meet the criteria of the protocol. Currently, they are updating cancers of the breast, prostate, colorectum and pancreas. Breast cancer survivorship, then cancers of the endometrium, ovarian, bladder and kidney are scheduled to follow.
"The crucial element is that we collect all the relevant information in the database and that all the information is accurate," says Norat. "You can repeat the analysis 20 times but it won't solve anything if articles are missing or if the information is wrong." To ensure the accuracy of the database, two researchers verify the selected studies and how data from each study are entered.
The number of studies is growing, says Norat, with more cohort studies than previously considered and more from Asia. The most active area of research relates to diet, physical activity and weight and breast cancer.
The CUP's first cancer type investigated was breast cancer. In September 2009, the CUP confirmed the findings of AICR/WCRF's expert report: excess body fat (post-menopausal) and drinking alcohol increased risk; being physically active and breastfeeding reduced the risk of breast cancer. The WCRF global network expects to publish its report on colorectal cancer this Spring/Summer, with a report on pancreatic cancer and breast cancer survivorship due to follow.
By 2015, CUP plans to have updated the evidence for all cancer types associated with food, nutrition, physical activity and body fatness. At that point, ongoing updates will continue for all sites. Thus far, researchers have added over 100 studies to the 2007 report's database for breast cancer.
"Once the database has been updated to include all papers for all sites, it will be made available to researchers around the world," says Thompson. Access to the database will give researchers access to high quality data, and allow them to conduct their own analyses, and look for gaps in the research. "Hopefully the database will inspire researchers to conduct studies that can eventually be added to the database. The database will largely be used for research purposes but the findings from the Continuous Update Project will enable AICR/WCRF to ensure our Recommendations are based on the best evidence and health professionals can feel confident in talking about these recommendations to their patients."