What Causes Pancreatic Cancer?
Normal cells in the body follow an orderly path of growth, division, and death. Cancer cells however grow uncontrollably and do not die when they are supposed to. Scientists do not know all the reasons why this happens but we have understood alot about cancer through research.
Cells can experience uncontrolled growth if there is damage or mutations in the DNA. Four key types of genes are responsible for controlling the cell growth process: oncogenes tell cells when to divide, tumor suppressor genes tell cells when to stop dividing, DNA-repair genes help fix DNA when it is damaged and suicide genes tell cells to kill themselves if DNA is not reparable.
Cancer is the result when a cell's DNA mutations make the cell, grow when it shouldn’t or not die when it should. In pancreatic cancer, most DNA mutations are a result of factors that damaged DNA after a patient was born rather than a result of inheritance from parents.
There are a small number of pancreatic cancer patients however that inherited their mutated DNA from their family. About 10% of pancreatic cancers are though to be caused by inherited gene mutations. Genetic syndromes that are associated with pancreatic cancer include hereditary breast and ovarian cancer syndrome, pancreatitis, and non-polyposis colorectal cancer (Lynch syndrome).
Carcinogens are a class of substances that are directly responsible for damaging DNA, promoting or aiding cancer. Cigarette smoke contains close to 50 different carcinogens that have been shown to be harmful to humans. About one-third of pancreatic cancer cases are thought to be a direct result of cigarette smoking. Other carcinogens found in certain pesticides, dyes, and chemicals related to gasoline have also been linked to pancreatic cancer.
There are several other medical factors are known to increase the risk of developing pancreatic cancer. These include:
- Age: The risk of developing cancer of the pancreas increases after age 50. Most patients are between age 60 and 80 at the time of the diagnosis.
- Gender: Men are about 30% more likely to develop pancreatic cancer compared to women, but this difference is narrowing.
- Race: African Americans are more likely to develop pancreatic cancer than are white Americans or Asian.
- Diabetes mellitus: Diabetic individuals are twice as likely to develop pancreatic cancer compared to non-diabetic individuals. The reason for this association is not known.
- Chronic pancratitis: Patients with chronic pancreatitis may have an increased risk of developing pancreatic cancer.
Diet and obesity have also been linked to cancers of the pancreas. People who do not exercise much and who are obese are more likely to develop pancreatic cancer. In addition, those who eat diets low in vegetables and fruits and high in red meat and fat are more likely to be diagnosed with the disease. On the other hand, a diet high in fruits, vegetables, and dietary fiber appears to have a protective effect and to reduce
the risk of pancreatic cancer.
Alcohol consumption is also considered a risk factor for pancreatic cancer. Long term, heavy drinking leads to chronic pancreatitis, which is a known risk factor for pancreatic cancer.