Colorectal cancer is cancer affecting the colon and the rectum can also be called rectal cancer, colon cancer or bowel cancer. It is the third most common cancer occurring both in women and men. Countries, where people are affected, are Australia, New Zealand, Canada, United States and some parts of Europe, China, India and South America are at lower risk.
Symptoms of Colorectal Cancer:
- Constipation or diarrhoea
- Change in bowel habits
- Blood in stools that makes it appear black
- Pain and bloating of the stomach
- Feeling that bowel doesn’t empty even after a bowel movement
- Feeling full in the abdomen even without eating
- Weight loss
- Iron deficiency in men and women
Risk Factors of Colorectal Cancer:
Many risk factors are associated with colorectal cancer. They are
- Age – more than 90% of cancer cases are seen in people of age 50 or older and the chances increase between 60 to 79 years. But the present trend also shows that younger people can also be diagnosed.
- The family history of colorectal cancer
- Presence of polyps in rectum and colon that later become cancerous
- Inflammatory bowel disease or Crohn disease or ulcerative colitis
- Inherited genetically
- Nutritional habits – diet has a very strong influence on causing colorectal cancer and change in diet can reduce up to 70% risk. High animal fat diet mainly red meat and a diet low in fiber, fruits and vegetables are main causing factors.
- Lack of physical activity
- Excessive alcohol consumption.
Causes of Colorectal Cancer:
Cancer is caused by changes in a chemical component of DNA. These changes lead to mutations and cause uncontrolled growth of cells which becomes cancer.
The common forms of inherited colon cancer are
- Hereditary nonpolyposis colorectal cancer (HNPCC) – also called Lynch syndrome. It is caused by a mutation in genes that are involved in DNA repair - MLH1 and MSH2 genes. They are also responsible for causing other cancers as well like uterus, stomach, pancreas, kidney, and ureter.
- Familial adenomatous polyposis (FAP) – it is a rare disorder that causes the growth of polyps in the lining of the colon and rectum.
Diagnosis of Colorectal cancer:
After knowing the signs and symptom the doctor advises for
- Fecal occult blood testing – testing fecal sample in the laboratory
- Colonoscopy – a thin, flexible tube is inserted in the rectum and checked for polyps.
Staging colon cancer-
The stages of colon cancer are:
- Stage I – cancer growth doesn’t spread beyond the colon or rectum wall
- Stage II – cancer growth reaches into the wall of colon or rectum but doesn’t spread to lymph nodes
- Stage III – invades to lymph nodes but not to other parts of the body
- Stage IV – spreads to other organs
Treatment of Colorectal cancer:
Depending on the severity of cancer the treatment is decided. The treatments are surgery, chemotherapy, and radiation.
- Surgery – for the early stage of cancer surgery can be done by removing the polyps. At the later stages, a part of the colon containing the cancer is removed. In advanced stages, surgery is an option to relieve pain and bleeding but doesn’t cure cancer.
- Chemotherapy – after surgery drugs are given to further manage the spread to lymph nodes by reducing the risk.
- Radiation – uses X-rays, to kill and shrink cancer cells for easy removal and relieving the symptoms. It can be combined with other treatments or given alone.
Prevention of Colorectal Cancer:
Lifestyle change and modifying the eating practices by consumption of fish, more fibre, vitamin D and calcium are proven to be beneficial. Always remember to consult a doctor and go for routine checkups.