April 5, 2019
By: Dr. Amit Rana

Colon Cancer

Forget swallowing bubblegum and fearing it being stuck in your intestine and stomach for days and finally getting operated to remove the gum from your body, colon cancer beats this and every other major digestive affliction. Colon cancer is a type of cancer where the large intestines form polyps which later turn into cancer.  Colon cancer or colorectal cancer starts from the colon or the rectum, named depending on where they start. It is the third most common cancer in men and the second most common in women.

 Risk factors:

1) Inherited mutated gene that increases the risk of colon cancer

2) African-American race

3) Old-age

4) Dietary habits with low fiber consumption, high fat and low water intake

5) Inflammatory intestinal conditions and radiation therapy

6) Diabetes, smoking, alcohol consumption and sedentary lifestyle with no


7) The family history of colon cancer, polyps and inherited syndromes that

       increase the risk of colon cancer


The most common inherited syndromes are-

1)  Familial adenomatous polyposis (FAP) - People with this syndrome have a

      higher risk of developing colon cancer before the age of 40

2)  Hereditary non-polyposis colorectal cancer (HNPCC), also called Lynch

      syndrome - People with this syndrome have a higher risk of developing colon

      cancer  before the age of 50


Stages and Diagnosis:

  • Stage I – Cancer grows through the mucosa but doesn’t move beyond the colon wall.
  • Stage II - Cancer grows through the wall
  • Stage III - Cancer grows into the lymph nodes but not into nearby body regions.
  • Stage IV - Cancer invades distant parts, ex. Liver.


Once the signs and symptoms indicate the probability of colon cancer, diagnosis is as follow-

1) Blood tests – Although blood test cant reveals colon cancer, it may show the functions of body parts and clues to the overall health. The carcinoembryonic antigen or CEA, found in the colon, tested through blood tests, shows how well the diseased colon is responding to the treatment and shows the status of the prognosis.

2) Fecal immunochemical test (FIT) and guaiac-based fecal occult blood test (gFOBT) – the blood in these tests could be the sign of large polyps.

3) Stool DNA testing – Shows whether the DNA taken from the stool for testing has genes with aberrations that could possibly lead to colon cancer.

4) Colonoscopy – Here a long slender tube with a video camera attached at the operating end is sent along the colon and rectum to look for abnormal growths and if found tools are sent to take tissue samples and for biopsies.

5) CT colonography / virtual colonoscopy - Finding the cross-sectional areas of the colon and rectum using CT scans.

6) Flexible sigmoidoscopy - Not famously used, this looks for certain parts of the colon. It is done every 5 years. 

The treatment for colon cancer includes radiation therapy, proton beam therapy, immunotherapy, chemotherapy, targeted drug therapy, and extensive palliative care. Clinical trials are always at the reach of the hand for those who are willing to go ahead with it.