What are Pancreatic Cancer Risk Factors?
Pancreatic cancer risk factors
A risk factor is anything that affects your chance of getting a disease such as cancer. Different cancers have different risk factors. Some risk factors, like smoking, can be changed. Others, like a person’s age or family history, can’t be changed.
But having a risk factor, or even several risk factors, does not mean that you will get the disease. And many people who get the disease may have few or no known risk factors.
Several factors can affect a person’s chance of getting cancer of the pancreas. Most of these are risk factors for exocrine pancreatic cancer.
Risk factors that can be changed
Smoking is one of the most important risk factors for pancreatic cancer. The risk of getting pancreatic cancer is about twice as high among smokers compared to those who have never smoked. About 20% to 30% of pancreatic cancers are thought to be caused by cigarette smoking. Cigar and pipe smoking also increase risk, as does the use of smokeless tobacco products.
Overweight and obesity
Being overweight is a risk factor for pancreatic cancer. Very overweight (obese) people are about 20% more likely to develop pancreatic cancer.
Carrying extra weight around the waistline may be a risk factor even in people who are not very overweight.
Workplace exposure to certain chemicals
Heavy exposure at work to certain chemicals used in the dry cleaning and metal working industries may raise a person’s risk of pancreatic cancer.
Risk factors that can’t be changed
The risk of developing pancreatic cancer goes up as people age. Almost all patients are older than 45. About two-thirds are at least 65 years old. The average age at the time of diagnosis is 71.
Men are slightly more likely to develop pancreatic cancer than women. This may be due, at least in part, to higher tobacco use in men, which raises pancreatic cancer risk (see above). The difference in pancreatic cancer risk was larger in the past (when tobacco use was much more common among men than women), but the gap has closed in recent years.
African Americans are slightly more likely to develop pancreatic cancer than whites. The reasons for this aren’t clear, but it may be due in part to having higher rates of some other risk factors for pancreatic cancer, such as diabetes, smoking in men, and being overweight in women.
Pancreatic cancer seems to run in some families. In some of these families, the high risk is due to an inherited syndrome (explained below). In other families, the gene causing the increased risk is not known. Although family history is a risk factor, most people who get pancreatic cancer do not have a family history of it.
Inherited genetic syndromes
Inherited gene changes (mutations) can be passed from parent to child. These gene changes may cause as many as 10% of pancreatic cancers. Sometimes these changes result in syndromes that include increased risks of other cancers (or other health problems). Examples of genetic syndromes that can cause exocrine pancreatic cancer include:
Hereditary breast and ovarian cancer syndrome, caused by mutations in the BRCA1 orBRCA2 genes
Familial atypical multiple mole melanoma (FAMMM) syndrome, caused by mutations in thep16/CDKN2A gene
Familial pancreatitis, usually caused by mutations in the PRSS1 gene
Lynch syndrome, also known as hereditary non-polyposis colorectal cancer (HNPCC), most often caused by a defect in the MLH1 or MSH2 genes.
Peutz-Jeghers syndrome, caused by defects in the STK11 gene. This syndrome is also linked with polyps in the digestive tract and several other cancers.
Von Hippel-Lindau syndrome, caused by mutations in the VHL gene. It can lead to an increased risk of pancreatic cancer and carcinoma of the ampulla of Vater.
Pancreatic neuroendocrine tumors and cancers can also be caused by genetic syndromes, such as:
Neurofibromatosis, type 1, which is caused by mutations in the NF1 gene. This syndrome leads to an increased risk of many tumors, including somatostatinomas.
Multiple endocrine neoplasia, type I (MEN1), caused by mutations in the MEN1 gene. This syndrome leads to an increased risk of tumors of the parathyroid gland, the pituitary gland, and the islet cells of the pancreas.
Changes in the genes that cause some of these syndromes can be found by genetic testing. For more information on genetic testing, see Can pancreatic cancer be found early?.
Pancreatic cancer is more common in people with diabetes. The reason for this is not known. Most of the risk is found in people with type 2 diabetes. This type of diabetes most often starts in adulthood and is often related to being overweight or obese. It’s not clear if people with type 1 (juvenile) diabetes have a higher risk.
Chronic pancreatitis, a long-term inflammation of the pancreas, is linked with an increased risk of pancreatic cancer (especially in smokers), but most people with pancreatitis never develop pancreatic cancer.
Chronic pancreatitis is sometimes due to an inherited gene mutation. People with this inherited (familial) form of pancreatitis have a high lifetime risk of pancreatic cancer.
Cirrhosis of the liver
Cirrhosis is a scarring of the liver. It develops in people with liver damage from things like hepatitis and heavy alcohol use. People with cirrhosis seem to have an increased risk of pancreatic cancer.
Infection of the stomach with the ulcer-causing bacteria Helicobacter pylori (H. pylori) may increase the risk of getting pancreatic cancer. Some research has suggested that excess stomach acid might also increase the risk.
Factors with unclear effect on risk
Some studies have linked pancreatic cancer to diets that are high in red and processed meats (such as sausage and bacon) and low in fruits and vegetables. But not all studies have found such links, and this is still being studied.
Some research has suggested that lack of physical activity might increase pancreatic cancer risk. But not all studies have found this.
Some older studies have suggested that drinking coffee might increase the risk of pancreatic cancer, but more recent studies have not confirmed this.
Some studies have shown a link between heavy alcohol use and pancreatic cancer. This link is still not certain, but heavy alcohol use can lead to conditions such as chronic pancreatitis and cirrhosis, which are known to increase pancreatic cancer risk.