Link found between obesity, oesophageal cancer

New Irish study:Overweight men run a much greater risk of contracting a lethal cancer with a one-in-10 survival rate than men of normal weight, according to a new Irish study.

The first Irish study on obesity and cancer, carried out by a research team at St James's Hospital in Dublin, shows that obese men are 11 times more likely to develop a type of oesophageal cancer.

Oesophageal adenocarcinoma is an aggressive tumour that has increased more in the western world than any other cancer. Only one in 10 patients survive more than five years having contracted the condition.

There has been a 38 per cent rise in the incidence of oesophageal cancer in Ireland in the past 15 years. Rates here are among the highest in the EU, and obesity accounts for 41 per cent of cases of the condition in the western world. The average age of men presenting with the condition is 66, but those who contract it in their 40s and 50s have an even lower survival rate.

The study, led by research dietician Aoife Ryan in conjunction with John Reynolds, professor of surgery at St James's, involved 760 cancer patients who were treated at the hospital over a 10-year period.

The research team examined how overweight the patients were a year before getting cancer and compared the information with 900 healthy controls. Other risk factors such as age, smoking, alcohol intake and a history of acid reflux were factored into the study. Some 82 per cent of patients with this cancer were overweight or obese prior to their illness.

The obesity risk of oesophageal cancer is unique to men and may be because men carry excess weight on their abdomen, which is known to be dangerous for a number of chronic illnesses including cancer. The deep "visceral" fat secretes hormones which encourage cancer growth.

"The fact that obesity is fuelling the increase in this form of cancer is very worrying," Ms Ryan said.

"People are very unaware of the link. The attitude toward men with beer bellies is often that they are cute. But in fact they are at much higher risk of cancer."

She said men with waist circumferences of 102cm (40 inches) or more were obese, and in Ireland 57 per cent of men over 51 years were overweight or obese.

However, risk factors associated with obesity can be greatly reduced by a weight loss of just 10 per cent.

She also highlighted the increase in childhood obesity in Ireland. "Paediatric obesity trends are worrying because not only is obesity in children a strong predictor of adult obesity, but children with increased central fatness show hormonal changes described as risk factors for cancer in obese adults."

Obesity accounts for 14 per cent of cancer deaths in men. Recent studies suggest that within the next 10-15 years, three-quarters of the population will be overweight and obesity may overtake smoking as the number one factor linked with cancer risk.

The World Health Organisation predicts that global cancer rates could increase by 50 per cent to 15 million by 2020.

Ms Ryan advised that anyone experiencing swallowing problems and sudden weight loss, or anyone who is obese and suffering with acid heartburn, should visit their doctor.