Colon Cancer

The colon is also called large intestine which is the terminal part of the alimentary tract. Cancer that develops in this part is called colonic cancer.

Though Colon cancer typically affects older adults it can happen at any age. They normally start as small polyps, later they turn malignant. Rectum is the final part of the colon and cancer which develops here is called rectal cancer

Signs & Symptoms

  1. A persistent change in the bowel habits, including diarrhea or constipation or a change in the consistency of the stool
  2. blood in the stool
  3. Persistent abdominal discomfort
  4. Weakness or fatigue
  5. Unexplained weight loss & loss of appetite

Risk factors

Factors that may increase the risk of colon cancer include:

  1. Older age.
  2. Presence of polyps in colon
  3. Inflammatory intestinal conditions such as crohns or ulcerative colitis. .
  4. Inherited syndromes that increase colon cancer risk that can run in families – . familial adenomatous polyposis (FAP) and Lynch syndrome, which is also known as hereditary nonpolyposis colorectal cancer (HNPCC).
  5. Family history of colon cancer.
  6. Low-fiber, high-fat diet.
  7. A sedentary lifestyle.
  8. Diabetes
  9. Obesity
  10. Smoking
  11. Alcohol

Diagnosing colon cancer

  1. Using a scope to examine the inside of the colon (colonoscopy).Colonoscopy uses a long, flexible and slender tube attached to a video camera and monitor to view the entire colon and rectum. If any suspicious areas are found, tissue samples (biopsies) can be taken
  2. Blood tests.A low haemoglobin levels should be a trigger for further investigations to rule out colonic malignancy. Carcinoembryonic antigen, or CEA is a specific tumour marker for colonic cancer. This is also used to see the response to treatment.
  3. CT SCAN – This is one of the mainstay investigations to stage the disease and to understand if it has spread to other parts of the body. If the tumour is in the rectum then a MRI scan will be done to know the local spread of the tumour.
  4. PET-CT – A Pet scan will be done to see if there is any distal spread of the tumour.

Based on these investigations a staging of the tumour will be done.

Treatment

Treatment  will depend on staging of the bowel cancer. As in any cancer the three main treatment options are Surgery, Chemotherapy & Radiotherapy. Most of the time they will be used in various combinations and in varying sequence to achieve maximum results. 

Surgery

The type of surgery will depend on the position of the tumour as shown in the diaphragm. If the tumour is situated very low down the large intestine then a an artificial passage to pass stools will be created (Stoma). At times a stoma will be created on temporary basis and will be closed at a later date.

Chemotherapy

Chemotherapy uses drugs to destroy cancer cells. Chemotherapy for colon cancer is usually given after surgery if the cancer is larger or has spread to the lymph nodes. In this way, chemotherapy may kill any cancer cells that remain in the body and help reduce the risk of cancer recurrence.

Chemotherapy might also be used before an operation to shrink a large cancer so that it’s easier to remove with surgery

Radiation therapy

Radiation therapy uses powerful X-rays to kill cancer cells. It might be used to shrink a large cancer before an operation so that it can be removed more easily.

When surgery isn’t an option, radiation therapy might be used to relieve symptoms, such as pain. Sometimes radiation is combined with chemotherapy.

Immunotherapy

Immunotherapy is a drug treatment that uses the immune system to fight cancer. The body’s disease-fighting immune system may not attack the cancer because the cancer cells produce proteins that blind the immune system cells from recognizing the cancer cells. Immunotherapy works by interfering with that process.

Immunotherapy is usually reserved for advanced colon cancer.

Supportive (palliative) care

Palliative care is provided by teams of doctors, nurses, social workers and other specially trained professionals They focus on providing relief from pain and other symptoms of a serious illness. Thereby increase the quality of life not only for the patients but also for the families.  

Prevention

Screening colon cancer

Doctors recommend that people with an average risk of colon cancer consider colon cancer screening around age 50. But people with an increased risk, such as those with a family history of colon cancer, should consider screening sooner.

Other lifestyle changes are as follows

  1. Eat a variety of fruits, vegetables and whole grains.
  2. Drink alcohol in moderation, if at all.
  3. Stop smoking.
  4. Exercise most days of the week.
  5. Maintain a healthy weight.