Causes of Rectal Cancer


The exact causes of rectal cancer remain unknown, but there are numerous risk factors that lead to increased chances of developing rectal cancer. Some of these risk factors include:
  • High Fat Intake: A high fat diet increases the risk of developing rectal cancer. Studies conducted show a definite correlation between a high fat intake and the incidence of rectal cancer. This may be because of the formation of carcinogens (cancer causing compounds) as a byproduct of fat metabolism. Diets that are rich in vegetables, fruits and whole-grain cereals can help the body get rid of these carcinogens and reduce the risk of rectal cancer.
  • Polyps in the Large Intestine: Conventional scientific belief suggests that most rectal cancers develop in rectal polyps. Early detection and removal of these polyps is therefore the best way to reduce the risk of developing rectal cancer. Polyps develop when the chromosomes of cells lining the rectum get damaged. Chromosomes govern the growth of cells and any damage to them may make them can cause unrestrained cell growth leading to the formation of polyps. Colon and rectal polyps are initially benign, but over the years, additional damage may make them cancerous.
  • Chronic Ulcerative Colitis: This causes an inflammation in the inner lining of the colon and the rectum. Over a period of time this may develop into colorectal cancer. The risk begins to increase after about 10 years of ulcerative colitis, with current estimates putting it at 2.5% at 10 years increasing to 10.8% at 50 years.
  • A Family History of Colorectal Cancer: Genetic background plays a big role in rectal cancer risk. People with a family history of colorectal cancer have three time higher chances of developing the disease compared to the general population. However, 80% of all colorectal cancers occur in people with no previous family history of colorectal cancer.
About 5% of colorectal cancers are due to hereditary cancer syndromes like FAP (familial adenomatous polyposis). Unless detected and removed early, these are sure to develop into colorectal cancer.



Frequently asked questions
References
  1. Maria Giulia Zampino, Roberto Labianca, Giordano Beretta, Gemma Gatta, Katia Lorrizo, Filippo de Braud, Jacques Wils, Rectal cancer, Critical Reviews in Oncology/Hematology, Volume 51, Issue 2, August 2004, Pages 121-143, ISSN 1040-8428, 10.1016/j.critrevonc.2004.03.004.
  2. E.M. Tweedle, P.S. Rooney, A.J.M. Watson, Screening for Rectal Cancer – Will it Improve Cure Rates?, Clinical Oncology, Volume 19, Issue 9, November 2007, Pages 639-648, ISSN 0936-6555, 10.1016/j.clon.2007.07.002.
  3. Rob Glynne-Jones, Pawan Mathur, Colin Elton, Matthew L. Train, Multimodal treatment of rectal cancer, Best Practice & Research Clinical Gastroenterology, Volume 21, Issue 6, December 2007, Pages 1049-1070, ISSN 1521-6918, 10.1016/j.bpg.2007.11.003.