Causes of Pancreatic Cancer:
The exact causes of of pancreatic cancer are not known. DNA is the substance that stores the biological instructions pertaining to growth, development and functioning of cells. The genes that are responsible for the cell division are as follows:
- Oncogenes: the genes that help cells grow, multiply and stay alive.
- Tumour suppressor genes: the genes that control cell division, repair mistakes of the DNA and cause timely death of the cells.
- The permanent alteration in the DNA sequence is called gene mutation. Cancer is known to develop due to genetic mutations. Genetic mutations are divided into two categories.
- Inherited gene mutations: Certain inherited conditions or syndromes can cause these mutations.
- Acquired gene mutations: These occur after birth and due to exposure to cancerous agents. Pancreatic cancers are mostly due to acquired gene mutations.
When the exact causes are of cancer are not known, certain conditions are identified to increase the chances of developing the cancer and these are called the risk factors. The presence of risk factors does not guarantee that a person gets cancer, nor does absence of risk factors prevent cancer, it only reflects higher probability of developing it. The following are the known risk factors of pancreatic cancer:
The possibility of developing pancreatic cancer increases with age. People below 40 rarely get it with over two thirds of the cases being over 65 years old and the average age of patients diagnosed is 71.
Men are noted to be more likely to develop pancreatic cancer than women and the exact reasoning for this is not known although it may be because of slightly higher consumption of tobacco too.
African Americans were noted to be more likely to develop pancreatic cancer than Caucasians, Asians or Hispanics and again, the exact reasons for this are not known.
Having one or two first degree relatives having pancreatic cancer is a known risk factor of this type of cancer.
Smoking is one of the major risk factors for pancreatic cancer and is thought to be responsible for about 20% to 30% of all pancreatic cancer cases. The risk of getting this cancer is two times higher in smokers as compared to non smokers.
People who were obese were noted to have 20% higher risk to develop pancreatic cancer than those who were not. It was also observed that people who exercised were half as likely to develop this cancer when compared to those who did not.
Heavy exposure to chemicals used in dry cleaning and metal industries increases the person’s risk of cancer.
Mentioned below are some of the inherited syndromes that cause pancreatic cancer.
- Hereditary breast and ovarian cancer syndrome
- Familial atypical multiple mole melanoma (FAMMM) syndrome
- Familial pancreatitis caused PRSS1 gene mutation
- Lynch syndrome
- Peutz Jeghers syndrome
- Von Hippel Lindau syndrome
The following syndromes cause pancreatic neuroendocrine tumours and related cancers too.
- Neurofibromatosis type 1
- Multiple endocrine neoplasia type 1
People with type 2 diabetes are noted to have higher risk of developing pancreatic cancer though the exact reason is not known, type 2 diabetes is associated with old age and often related to obesity too. It is not known if type 1 diabetes increases the risk of pancreatic cancer too.
Chronic Pancreatitis is the inflammation of pancreas that does not heal with time and leads to permanent damage. It develops between the ages 30 to 40 and is more common in men than in women with a prevalence of about 50 in a 100,000 people. The ability to digest food and make hormones gets impaired in this condition and is a risk factor for pancreatic cancer.
This is a late stage of scarring of liver which occurs in response to liver damage. When the liver is damaged, it tries to repair itself and scar tissue is formed in this process and this process cannot be undone and this increases the risk of pancreatic cancer.