The exact cause of pancreatic cancer isn't fully understood.
However, there are a number of risk factors that can increase your chances of developing it.
Pancreatic cancer can affect people of any age, but it mainly affects people who are aged 50 to 80. Almost 50% of people diagnosed with cancer of the pancreas are aged 75 or over.
Research has found that about one in three cases of pancreatic cancer is associated with smoking and other tobacco use.
Smoking cigarettes, cigars or chewing tobacco can all increase your risk of developing cancer of the pancreas.
This is because tobacco smoke contains harmful chemicals and toxins that can cause irritation and inflammation within your body's organs and tissues.
If you have diabetes, your risk of developing pancreatic cancer is thought to be increased.
However, it's important to remember that diabetes is very common, affecting more than 3 million people in the UK, and most people with diabetes won't develop pancreatic cancer.
As well as diabetes being a risk factor for pancreatic cancer, it's also thought that a cancerous tumour that grows in the pancreas could be responsible for some cases of diabetes.
Chronic pancreatitis and hereditary pancreatitis
Chronic pancreatitis (long-term inflammation of the pancreas) increases your risk of getting pancreatic cancer, but isn't responsible for many cases. Chronic pancreatitis is often caused by long-term alcohol misuse.
Although it's a very rare condition, if you have hereditary pancreatitis, your risk of developing pancreatic cancer is 50 times greater than the rest of the population.
Helicobacter pylori infection
Helicobacter pylori are bacteria that cause stomach ulcers, and is a known risk factor for stomach cancer.
Research has shown that a Helicobacter pylori infection may slightly increase your risk of getting pancreatic cancer. However, the risk is thought to be small because most people with this infection don't get cancer of the pancreas.
Other known risk factors
There are also a number of other factors that have been associated with an increased risk of pancreatic cancer. These are:
The Cancer Research UK website has more information about these other possible risk factors for pancreatic cancer.
What is cancer?
Cancer begins with a change (mutation) in the DNA in cells. This causes the cells to reproduce uncontrollably, producing a lump of tissue called a tumour.
Left untreated, cancer can grow and spread to other parts of the body.
Last updated: 05 January 2016
Can I inherit pancreatic cancer?
In about 1 in 10 cases, pancreatic cancer is inherited from a person's parents.
Certain genes can increase your chances of getting pancreatitis, which in turn increases your risk of developing cancer of the pancreas.
Read more about the genetic risk factors for pancreatic cancer on the Cancer Research UK website.
Continue to next section: Diagnosing pancreatic cancer