Rectal cancer is a serious health condition that affects thousands of people every year. Rectal cancer originates in the rectum – the last part large intestine, which is several inches long and is directly linked to the anus through a narrow passage. While the exact causes of rectal cancer remain largely unknown, there are several risk factors and lifestyle habits which can increase your likelihood of developing it. In this article, we’ll be discussing the possible causes of rectal cancer in greater detail, including how certain environmental factors may increase your risk.
How is Rectal Cancer Caused?
Most cases of rectal cancer are sporadic, that is, the mutation of the gene that causes cancer formation is acquired and not inherited from parents. A small amount of patients (only around 10%) show inherited patterns of rectal cancer. There are also several genetic and environmental risk factors that increase the chances of rectal cancer. The following reasons are usually found to be associated with rectal cancer occurrence:
- Genetic mutations - Mutations in the gene FAP (Familial Adenomatosis Polyposis) have been found to be associated with rectal cancer. Further mutation associated with genetic diseases like Lynch syndrome, i.e. hereditary non-polyposis colorectal cancer [HNPCC], has been found to cause rectal cancer. People with Lynch syndrome, another genetic disorder, show up to 80% risk of developing rectal cancer. People with a FAP mutation also show a 100% lifetime risk of developing rectal cancer if they leave the polyps in the colorectal region untreated.
- Family history – People with a family history of colon cancer, adenomatous polyps, and polyps with villus are at a higher risk of getting rectal cancer.
- Development of inflammatory bowel disease – Patients with inflammatory bowel disease or Crohn’s syndrome are more prone to developing rectal cancer.
Other risk factors for developing rectal cancer include the following:
- Age – The chances of getting rectal cancer increase with advancing age.
- Unhealthy lifestyle – Following an unhealthy lifestyle with a non-nutritious diet, smoking, alcohol intake, and physical inactivity increases the risk of developing rectal cancer.
- Lifestyle diseases – Diseases that occur due to a bad lifestyle, like diabetes and obesity, can also increase the chances of getting rectal cancer.