A study to understand more about indicators of bowel cancer risk in people who are overweight

Cancer type:

Bowel (colorectal) cancer

Colon cancer

Status:

Results

Phase:

Other

This study looked to see if certain indicators (biomarkers) of cancer risk change after weight loss.

We know that people who are overweight have a slightly increased risk of developing cancer of the large bowel (colon). Researchers wanted to find out why this is.

Inflammation in the bowel increases risk of bowel cancer. People who are overweight have higher blood levels of proteins that control inflammation. Researchers wanted to find out if losing weight decreases bowel inflammation, which may lower bowel cancer risk.

They looked at blood, urine and stool samples to measure levels of inflammation proteins. And they looked at tissue samples to measure the rate that bowel cells divide and die.

The aims of this study were to find out if weight loss is linked to a

Decrease in bowel inflammation
Healthier rate of cell growth and death in bowel tissue

Summary of results

The research team found that the level of some factors changed after weight loss.

This study recruited

21 people who had a body mass index BMI of 40 or more (they were morbidly obese)
20 people who weren’t obese and had a BMI between 18.5 and 29.9

The people who were obese were due to have an operation to reduce the size of their stomach. This is called a sleeve gastrectomy and helps people lose weight.

The research team looked at the levels of proteins including C-reactive protein (CRP), interleukin-6 (IL-6) Open a glossary item and tumour necrosis factor (TNF) . They found that these were increased in people who were obese, compared to those who were not. The level of CRP fell significantly when people lost weight after a sleeve gastrectomy, but there was no significant change in the level of the other proteins.

When they looked at the bowel cells, they found that cells in people who were obese divided more quickly than those in people who weren’t obese. They also found that this didn’t change in the 6 months after surgery (it does after different type of weight loss surgery called a gastric bypass).

The research team found that some factors which indicate the level of inflammation in the bowel fell when people lost weight after a sleeve gastrectomy. They concluded that this should be looked at in more detail in a larger trial.

We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item ) and published in a medical journal. The figures we quote above were provided by the trial team. We have not analysed the data ourselves.