Risk factors for pancreatic cancer
We don’t properly understand exactly what causes pancreatic cancer, although we do know some risk factors. A risk factor is anything that increases your chances of getting a disease.
The causes of cancer are complex. It may be caused by a variety of things, including your genetic make-up and lifestyle choices, such as smoking. Although scientists now know more about the causes of cancer, we still need more research.
A lot of the evidence about the risk factors for pancreatic cancer is unclear. Some studies may find that something increases the risk, while others may show that it has no effect. And there may be other risk factors that researchers haven’t yet found.
The information below is about the things research suggests may increase someone’s risk of pancreatic cancer. It’s important to remember that having some of the risk factors doesn’t mean you will definitely get pancreatic cancer. Remember too that people sometimes get pancreatic cancer, even if they don’t have any of the risk factors.
Pancreatic cancer is the 11th most common cancer in the UK. Around 9,600 people are diagnosed with it each year. About 1 in 71 people will get pancreatic cancer at some point in their life.
What are the known risk factors?
Some evidence has suggested that the following may also increase your risk:
- red and processed meat
- history of cancer
- blood group
- stomach or gall bladder surgery
- Helicobacter pylori infection
We need more research to show whether these definitely do increase your risk.
Main risk factors that we know about
The risk of developing pancreatic cancer increases with age, as it does for many cancers. In the UK, more than nine out of ten (96%) people diagnosed with pancreatic cancer are aged over 50.
We know that smoking can cause pancreatic cancer. This includes smoking cigarettes, cigars and pipes, and chewing tobacco.
It’s estimated that smoking causes nearly one in three pancreatic cancer cases (29%) in the UK. Your risk of pancreatic cancer increases the more you smoke, and the longer you have smoked for.
Stopping smoking can reduce the risk of pancreatic cancer. About 20 years after stopping, your risk may return to what it would be if you had never smoked.
It’s not clear whether breathing in someone else’s smoke (passive smoking) increases the risk of pancreatic cancer.
Research shows that being overweight increases the risk of pancreatic cancer. Around one in ten pancreatic cancers (10%) may be caused by being overweight or obese.
Researchers think that in the UK, around one in six pancreatic cancer cases (16%) could be prevented each year if we all kept to a healthy weight.
Occasionally, pancreatic cancer may run in a family. This is not common. It includes:
- families with two or more first-degree relatives (a parent, brother, sister or child) with pancreatic cancer
- families with three or more relatives with pancreatic cancer
- families with a family cancer syndrome and at least one relative with pancreatic cancer.
Family cancer syndromes are rare genetic conditions where a faulty gene increases the risk of pancreatic cancer. Up to one in ten (10%) pancreatic cancers may be caused by one of these conditions.
Read more about family history of pancreatic cancer.
Pancreatitis is inflammation of the pancreas. The main symptom is periods of tummy (abdominal) pain. The pain may come and go, but it can last for hours or days. Some people feel or are sick (nausea and vomiting) during the pain. Over time, the pain may happen more often and be more severe. Over many years, pancreatitis can start to cause other symptoms that are linked to problems digesting food. These can be similar to the diet symptoms that are caused by pancreatic cancer.
Hereditary pancreatitis is a rare type of pancreatitis that runs in families. It usually starts in childhood. About four in ten people (40%) with hereditary pancreatitis will develop pancreatic cancer by the age of 70-75. The risk may be higher for people who also smoke or have diabetes.
Chronic pancreatitis is long-term pancreatitis. It is usually caused by heavy drinking over many years. People with chronic pancreatitis have an increased risk of developing pancreatic cancer.
NHS Choices has more information about pancreatitis, including the symptoms.
Diabetes is a condition where your blood sugar level isn’t properly controlled. The blood sugar level is controlled by a hormone called insulin, which is produced by the pancreas.
People with diabetes may have a higher risk of developing pancreatic cancer. However, diabetes is common and most people with diabetes won’t get pancreatic cancer.
Diabetes can also be a symptom of pancreatic cancer. A symptom is any change or problem that may suggest that you have a disease. Anyone over 60 who develops diabetes and starts to lose weight without any clear cause should go to their GP.
Some studies have suggested that people with diabetes who use the drug metformin may have a lower risk of pancreatic cancer. However, other studies have found that metformin makes no difference.
Other possible risk factors
Some research has suggested that these things may increase your risk of pancreatic cancer. But we need more research into them.
Some studies found that heavy drinking (more than three glasses of any alcoholic drink a day) may increase the risk of developing pancreatic cancer, and of getting it at a younger age. The risk may be higher still for people who smoke as well as drink heavily.
Drinking a moderate amount of alcohol doesn’t appear to increase the risk of pancreatic cancer.
Processed meat may increase the risk of pancreatic cancer. Eating around one serving (50g) a day may increase your risk. Processed meat is meat that has been preserved by smoking, curing, salting or adding chemical preservatives. It includes sausages, ham, bacon, salami and burgers.
Red meat may also increase the risk of pancreatic cancer. Red meat includes beef, lamb and pork.
You may have a higher risk of getting pancreatic cancer if you have already had some other cancers. These include cancers of the digestive system, breast, uterus (womb), cervix (neck of the womb), lung and testicular cancer. This may be because of lifestyle factors such as smoking, or it could be a genetic link. Some treatments for cancer, such as radiotherapy, may also increase your risk of getting another cancer.
There is some evidence that people with blood group A may have a higher risk of developing pancreatic cancer. On the other hand, people with blood group O may have a lower risk. We don’t know why blood group might affect your risk of pancreatic cancer, but it may be linked to genes.
The hepatitis virus is an infection that affects the liver. There are different types of hepatitis. Hepatitis B may increase the risk of pancreatic cancer. It isn’t very common in the UK. Hepatitis C may also increase the risk of pancreatic cancer, but the evidence for this is weaker.
There is some evidence that people who have had part of their stomach removed (gastrectomy) may have a higher risk of pancreatic cancer.
Evidence also suggests that people who have had their gall bladder removed (cholecystectomy) may have an increased risk of pancreatic cancer. You may have your gall bladder removed to treat painful gallstones.
Helicobacter pylori (H pylori) is a bacteria that causes stomach ulcers. Some studies have suggested that H pylori infection may increase the risk of pancreatic cancer, though we need more research into this.
Published December 2015
Review date December 2017