Establishing dietary and body size-related risk factors for oesophageal cancer to inform prevention: a pooled analysis of prospective studies
This project is co-funded with Cancer Australia
Cancers of the oesophagus are essentially two diseases – squamous cell carcinoma (88%) and adenocarcinoma (12%). Annually, over 600,000 oesophagus cancers are diagnosed worldwide. Though in some countries such as Australia, over half the oesophagus cancers are adenocarcinomas.
Around 550,000 people also die each year from oesophagus cancers globally. Over half the people diagnosed with oesophagus cancer die within a year of their diagnosis. In order to prevent these cancers and the deaths they cause, first we need to know what causes them.
It’s estimated that about 70% of the oesophagus cancers could be prevented by improving lifestyle including nutrition and body size.
The available evidence on risk factors for oesophagus cancers is based on small, mostly retrospective, studies and is often inconsistent. The best evidence comes from prospective studies where information on risk factors is collected before diagnosis which reduces bias.
Some prospective studies have examined risk factors for oesophagus cancers but they have usually not been comprehensive or examined subgroups because of the limited numbers of cases available in single studies.
According to the latest review of scientific evidence only smoking, alcohol consumption and obesity are known to cause one or both types of oesophagus cancer. Men have a higher risk of cancers of the oesophagus, which is explained only partly by smoking, alcohol and obesity.
This suggests that body fatness and diet might affect the risk of oesophagus cancer differently for men and women. These effects may also differ for smokers, heavy drinkers, obese individuals, and people from different regions.
Aims and Objectives
This study aims to determine whether:
- your risk of developing a cancer of the oesophagus is influenced by how much alcohol and other drinks (soft drinks, coffee, tea) you drink, how much meat and fish you eat, how much fruit, vegetables and cereal you eat, the amount of fibre in your diet, your body size and overall dietary and lifestyle pattern
- the strength of these risks differ between men and women, individuals in different geographical regions, smokers and non-smokers, heavy drinkers and light/non-drinkers, and obese and lean individuals.
How it will be done
The NCI Cohort Consortium, and the resources it shares with the Pooling Project of Prospective Studies of Diet and Cancer (DCPP), offers a not to be missed opportunity to definitively examine these issues using by far the largest sample available globally of prospectively collected data.
We will analyse data from 2.1 million people (participating in 21 high-quality international studies) 1,860 of whom have developed an adenocarcinoma and 1,288 a squamous cell carcinoma of the oesophagus during follow-up.
The participants’ individual data have already been collected and combined. The research team has demonstrated experience in leading this type of large international collaboration using the DCPP.
This project brings together the world’s highest-quality data available and expert researchers to generate the clear evidence required to inform policies to prevent oesophagus cancers. We estimate the study findings may help prevent nearly two-thirds of these cancers worldwide.