Investigation into the aetiology of small intestinal cancer in a pooled cohort
Principal Investigator:
Professor Elio Riboli
Approved Research ID:
28811
Approval date:
December 1st 2014
Lay summary
The small intestine is the longest structure in the gastrointestinal tract, yet it has only 5% or less of the cancers found here. Very little is known about the causes of small intestinal cancer (SIC) and few studies have been done mainly due to the limitation of the small number of cases. We propose a pooled study of over 2 million participants to examine the causes of SIC. The data collected from these cohorts, particularly diet, physical activity, anthropometric measurements, smoking alcohol drinking, comorbidities and medications will be examined being associated with SIC. The study is to investigate the aetiology of the small intestinal cancer (SIC) which meets the stated purpose of UK biobank. First, it is a ` health relate` research question to improve the prevention, diagnosis and treatment of SIC. Second, it is a `public interest` related question. Although, SIC is rare, the small intestine consists of more than 90% of the total surface area and more than 2/3 of the total length of gastrointestinal tract. The low incidence of SIC compared to the high prevalence of colon cancer is poorly understood. We are initiating a large-scale collaborative study to pool the data from different cohorts for the study of small intestinal cancer. The proposed project is designed as a nested case-control study, with 10 controls per case, matched by age, sex, ethnicity and geographical area of residence. Exposed data including diet (food frequency questionnaire), anthropometric data, physical activity, smoking, alcohol drinking, comorbidities and medications which were collected in the cohorts, will be examined to be associated with risk of small intestinal cancer. Conditional logistic regression with adjustment for potentials confounders will be performed based on hypothetical causality models. All the cases of small intestinal cancer and corresponding controls (1:10) will be included. It means one case will be matched by 10 controls. Around 100 small intestinal cancer will be estimated from the UK Biobank population based on previously reported incidence of small intestinal cancer. Thus totally 100 cases and 1000 controls will be expected to be included.