The exact cause of pancreatic cancer is not clear but certain factors have been identified as contributing to the risk for this condition.
All cancers are caused by the growth of abnormal cells. Genetic mutations alter the cellular regulatory mechanism for cell growth and multiplication. Cells containing such a mutation grow and proliferate in an abnormal manner, eventually giving rise to a tumor. Factors that increase the risk of damage to cellular DNA such as smoking or exposure to ultra violet light are therefore risk factors for cancer.
Some of the factors that increase the risk for pancreatic cancer include:
The risk for pancreatic cancer increases with age and the disease is most common in people aged 60 and above. Pancreatic cancers are rare in individuals below the age of 40.
The risk of developing pancreatic cancer is at least doubled among smokers and about 20% to 30% of exocrine pancreatic tumors are thought to be caused by smoking. Quitting smoking is one of the most important measures a person can take to reduce their risk of pancreatic cancer.
A diet that is rich in red and processed meat, sugar and fat but low in fibre, fresh fruit and vegetables increases the risk for pancreatic cancer.
Research shows that being overweight increases the risk for pancreatic cancer, with around 10% of cases in the UK linked to overweight.
Individuals with diabetes are at an increased risk of pancreatic cancer, although the risk is small. Specialists suggest that individuals aged over 50 years who suddenly develop diabetes should be evaluated for the possibility of pancreatic cancer.
Chronic inflammation of the pancreas
Chronic pancreatitis or long-term inflammation of the pancreas has been associated with an increased risk for pancreatic cancer. However, no causal relationship between the two conditions has been established in clinical studies.
Individuals with a family history of pancreatitis are at a greater risk of pancreatic cancer than those without such a family history. This rare condition is caused by inheritance of a faulty gene that will lead to the development of pancreatitis before the age of 75 years in around 50% of cases.
Excessive alcohol intake
In around 70% of cases, chronic pancreatitis develops as a result of long-term heavy drinking. Chronic pancreatitis is a risk factor for pancreatic cancer. However, no studies have established a firm link between heavy drinking and pancreatic cancer.
Around 5% to 10% of all pancreatic cancer patients have a family history of the condition. The condition can run in families but the exact genes that predispose to this cancer are yet to be identified.
Individuals who have at least one first degree relative who has suffered from pancreatic cancer are at twice the risk of developing the condition than those who have not had a family member develop the condition.
Risk for the condition is also increased among those with familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer and carriers of the breast cancer mutations BRCA1 or BRCA2.