Bowel Surgery

Bowel Surgery

The colon, also called the large intestine, is the terminal part of the digestive tract, colonised by enteric bacteria. Only water gets absorbed from the colon with all the nutrients being absorbed in the small intestine. Colonic bacteria is involved in a variety of functions such as the production of vitamin K; which is essential for the liver to produce certain coagulation factors.

Conditions that affect the colon:

  1. Colon cancer
  2. Diverticular disease
  3. Inflammatory bowel disease such as ulcerative colitis
  4. Polyps
  5. Loss of blood supply

Condition, Treatment & Procedure

Colon Cancer:

Colon cancer  is cancer of the large intestine, the lower part of the gastrointestinal system. Rectal cancer is cancer of the last 15cm  of the colon. These two conditions are often called colorectal cancers. Most cancers of the colon start as a noncancerous outgrowth of cells called polyps. Some of these polyps progress to become colon cancers.

 Polyps produce no symptoms. Regular screening tests prevent colon cancer by identifying and removing polyps before they become colon cancer usually by performing a colonoscopy.
Risk factors:
  • Age: The majority of people diagnosed with colon cancer are over the age of 50 years. Colon cancer can occur in younger people, but it occurs much less frequently.
  • Past history of colon cancer or polyps: If you’ve  had colon cancer or polyps, your risk is higher than other  people.
  • Inflammatory bowel disease: Chronic inflammatory diseases  such as ulcerative colitis and Crohn’s disease will increase your risk of getting colon cancer.
  • Low fibre and high-fat diet: The risk is higher in people who consume more dairy products and those who eat more red meat and processed meat.
  • Hereditary:  Certain familial syndromes can increase your risk of colon cancer. These syndromes include familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer, which is also called Lynch syndrome.
  • Family history of colon cancer:  The increase in the risk is proportional to the number of affected family members and the degree of relationship.
  • Diabetes: Insulin resistance may be associated with an increased risk of colon cancer.
  • Other factors: Overweight, Smoking, Alcohol, Radiation therapy for cancer.

Symptoms:

  • A change in your bowel habits, including diarrohea or constipation
  • Bleeding per rectum
  • Persistent abdominal discomfort, or pain
  • A feeling that your bowel doesn’t empty properly
  • Weakness or fatigue
  • Weight loss

Diagnosis:

When colon cancer is suspected your doctor will do a basic set of blood tests that may include tumour markers called CEA. You will be referred to have a colonoscopy, which will visualise the entire colon and biopsies will be taken if there is a cancerous growth.

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Staging: 

Once colon cancer is proved, certain tests are required to determine the stage of the cancer, which helps to determine the appropriate treatment.

Tests:
1. CT scan of the abdomen and chest to determine whether the cancer has spread to the liver and/or lungs. It may also demonstrate lymph nodes spread to some extent

2. PET scan: this is a form of nuclear medicine scan, the main purpose of the PET scan is ensure there is no spread to other organs

3. MRI of the liver: this will be requested if there are liver metastases to confirm the number of the lesions and their location in relation to main vascular structures.

The stages of colon cancer are:

  • Stage I: cancer has grown through  and limited to the superficial lining of the bowel.
  • Stage II: cancer has grown into or through the muscular wall of the colon without spread to lymph nodes.
  • Stage III: cancer has spread to the lymph nodes
  • Stage IV: cancer has spread to other organs such as the liver or the lungs
1. Removal of small cancer by colonoscopy in the very early stages
2.Endoscopic mucosal resection: larger polyps may  be removed along with a small area of the bowel inner lining
3. Partial removal of the colon:  During this procedure  part of your colon that contains the cancer is removed with a healthy margin and lymph nodes; it is usually possible in such elective situations to join the bowel and restore continuity
4. Creation of a colostomy: if it’s not possible to reconnect the  colon or rectum, you may need to have a colostomy, which could be either temporary or permanent.
5. Lymph node removal: it is a standard that draining lymph nodes are also removed during bowel cancer surgery and examined for spread of cancer.
6. Surgery for metastatic disease to the liver and lungs: in stage four disease surgery is still an option particularly if the spread was in the liver and/or lungs. Usually you will need chemotherapy and  are then referred to a Hepatobiliary surgeon for consultation to find out if the liver disease is removable, also a chest surgeon may be able to remove cancer that has spread to the lungs.
Chemotherapy:

Chemotherapy uses cytotoxic drugs to kill cancer cells that could exist but we can’t see it on imaging, these cancer cells could be anywhere, liver, lungs, bones and lymph nodes.

Chemotherapy for colon cancer is usually given after surgery if the cancer has spread to the lymph nodes. In this way, chemotherapy may help reduce the risk of cancer recurrence. On certain occasion you may need to have chemotherapy prior to having surgery. This is usually implemented in stage IV cancer.

In people diagnosed with rectal cancer, chemotherapy is typically used along with radiation therapy prior to the operation..