Researchers at the University of British Columbia in Canada have found a direct link between high insulin levels and the condition.
It provides the first detailed explanation as to why people with the two conditions are at increased risk of the fifth biggest cancer killer in the UK, with 9,000 deaths every year.
Pancreatic Cancer UK reports it is the tenth most common cancer in the country, with 10,500 people diagnosed in 2018.
Incidence rates are projected to rise by 5 per cent in the UK between 2023-2025 and 2038-2040, according to Cancer Research UK.
Pancreatic cancer had been linked to obesity and type 2 diabetes in the past but researchers had been unable to establish the cause prior to the research.
According to the new study, which was conducted on mice, excessive insulin levels overstimulate pancreatic acinar cells, which produce digestive juices. This overstimulation leads to inflammation that converts these cells into precancerous cells.
Co-senior author Dr James Johnson, a professor in the department of cellular and physiological sciences at the University of British Columbia (UBC), said: “Alongside the rapid increase in both obesity and type 2 diabetes, we’re seeing an alarming rise in pancreatic cancer rates.
“These findings help us understand how this is happening, and highlights the importance of keeping insulin levels within a healthy range, which can be accomplished with diet, exercise and in some cases medications.”
The new findings show insulin supports the physiological function of pancreatic acinar cells in producing digestive enzymes that break down fat-rich foods.
However, at high levels, the increased action can inadvertently foster pancreatic inflammation and the development of precancerous cells.
Researchers suggest it may pave the way for new cancer-prevention strategies and treatments that target insulin receptors in acinar cells.
Senior author Dr Janel Kopp, assistant professor in the department of cellular and physiological sciences at UBC, said: “We hope this work will change clinical practice and help advance lifestyle interventions that can lower the risk of pancreatic cancer in the general population.
“This research could also pave the way for targeted therapies that modulate insulin receptors to prevent or slow the progression of pancreatic cancer.”