"I was delighted to take part in a clinical trial as it has the potential to really help others in the future.”
A study looking at the causes of stomach cancer and food pipe cancer (SOCS)
This study looked at the possible causes of stomach and food pipe cancer (oesophageal cancer).
More about this trial
Doctors already know that there are various risk factors for stomach cancer and for oesophageal cancer. The researchers wanted to learn more about these known risk factors and anything else that may contribute towards the development of these cancers.
The researchers collected saliva and blood samples and information about lifestyle from people with stomach cancer and oesophageal cancer. The researchers also asked the partners of those with cancer to provide saliva and blood samples. The partners provided the
The aims of the study were
- To find out more about the known risk factors
- To look for new genetic and environmental risk factors
Summary of results
The researchers mainly looked at people with oesophageal cancer and Barrett’s oesophagus.
The researchers looked at the results of people taking part in this study as well as the results of other similar studies carried out across Europe, Australia and North America. Out of a total of 14 studies
- 1508 people had oesophageal cancer
- 2383 people had Barrett’s oesophagus
- 2170 people had neither cancer nor Barrett’s oesophagus and provided the control group for the study
One area the trial team looked at was the fact that more men are affected by oesophageal cancer than women. They concluded that one reason for this may be hormones.
Hormones are natural substances made by glands and organs in our bodies. Hormones are carried in our blood stream and act as messengers between one part of our body and another. There are many different hormones in the body.
Two hormones are oestrogen and oxytocin. Although they are found in both men and women, they are found at higher levels in women. Oxytocin is released during childbirth and breastfeeding and oestrogen plays an important part in the female reproductive system and the development of breast tissue.
The researchers think that there may be various explanations why higher levels of oestrogen and oxytocin are associated with a lower risk of oesophageal cancer. For example, higher oxytocin levels in the oesophagus and stomach may mean that the cells here are less likely to become inflamed and are more likely to heal following damage. But at the moment this is a theory. They don’t know this for sure.
Although this study involved large numbers of people, the numbers of women taking part was low compared to the number of men. So this meant that the researchers could not make as useful a comparison between the genders as they hoped to.
These findings need to be confirmed and explained in further research.
The researchers also recognised that the studies mainly involved white Europeans and so it may not be possible to apply the results to the population as a whole (or to other ethnic groups).
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Professor Carlos Caldas
Cambridge University Hospitals NHS Foundation Trust
Cancer Research UK
Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer