Colorectal cancer is cancer affecting the large intestine, and rectum. There has been rapid increase in colorectal cancer in India and this can be attributed to
1. Increasing life expectancy
2. Changing life style to western
Most cases occur above the age of 50. It is true that if detected early then colorectal cancer can be cured.
How does Colorectal cancer develop?
Contrary to belief it take years to develop colorectal cancer. It develops from the inner lining of bowel (mucosa). Initially it forms a polyp which over the time turns into cancer. Tumor then starts to invade through different layers of bowel wall then into to lymph nodes near by. If undetected, it can eventually spread to different parts of the body.
Most of these cancer are on the left side. (see pic)
Is there treatment for polyp?
Yes. Most polyps do not contain cancer cells. Removal of polyp will be sufficient to prevent the cancer from developing.
After removing the polyp, if cancer cells are found then it alone is sufficient if cancer cells are confined to polyp, however, if the cancer cells have spread to colon then further surgery is advised if necessary.
What are risk factors for Colorectal cancer?
- Increases with age
- Western life style
- Genetic factor (First degree relative having colorectal cancer)
- Long term inflammatory bowel disease (Crohns, Ulcerative colitis)
What reduces the chances of having colorectal cancer?
- Hormonal replacement therapy for woman
- Vegetarian diet
What are symptoms of colorectal cancer?
Initially there might be no symptoms or very little symptoms and become more when the cancer grows in size
- Change in bowel habit either to constipation or passing too many times
- Sensation of incomplete emptying after passing motion
- Blood mixed with the stool
- Passing mucus with stool
- Sensation fullness after eating little
- Abdominal distension
- Abdominal pain
- Weight loss
What tests are needed before surgery?
- Colonoscopy and biopsy to prove it is cancer is a must unless its an emergency
- CT scan to asses the spread inside the abdomen and chest
- MRI of pelvis if cancer is in rectum
What are the treatment options?
If it affects colon: Surgery is done first. After excision the cancer is looked under microscope, if it has spread to lymph nodes then chemotherapy might be needed post op.
If it affects rectum: In first two stages then surgery first.
If 3rd/4th stage then chemo radiotherapy first is absolutely must. Chemo-radiotherapy is given first then operating reduces risk of recurrence from 85% to 5% (See Pic)
If in Anal canal: Chemo radiotherapy is main stay of treatment.
How is Surgery done?
If the patient is fit cancer surgery can be done safely with keyhole (Laparoscopic) with 3 or 4 small incisions. Usually the cut ends are joined using special stapler. In certain cases, colostomy can be done if the joining is thought to be risky. The options will be discussed with risk/benefits before surgery.
Can the colorectal cancer be cured?
Yes, if found in early stages. Even if it has spread to lymph nodes, then also it is curable. People with liver metastasis can also be cured at times.