Bowel cancer is the second commonest cancer in women and third commonest cancer of men. It is the development of cancer in the colon or rectum (parts of the large intestine). It is due to the abnormal growth of cells that have the ability to invade or spread to other parts of the body. It is thought to start as a polyp in most cases which can turn into cancer over time. Signs and symptoms may include blood in the stool, a change in bowel movements, weight loss, and feeling tired all the time.
Risk factors for colorectal cancer include lifestyle, older age, inherited genetic disorders, diet, smoking, alcohol, lack of physical activity, family history of colon cancer and colon polyps, presence of inflammatory bowel disease like crohn’s or ulcerative colitis, presence of colon polyps, race, exposure to radiation, and even other diseases such as diabetes and obesity. People with family history of bowel cancer may be at a higher risk of developing polyps or cancers and should discuss screening with an expert.
Screening for bowel cancer is gaining recognition as it has the potential of preventing unnecessary deaths from bowel cancer. Screening programs vary between countries but screening over the age of 50 is recommended in several countries.
The signs and symptoms of bowel cancer depend on the location of the cancer in the bowel, and whether it has spread elsewhere in the body. The classic warning signs include: worsening constipation or diarrhoea, blood in the stool, decrease in stool caliber (thickness), loss of appetite, loss of weight, and nausea or vomiting.
Diagnosis
Bowel cancer is most commonly diagnosed by sigmoidoscopy or colonoscopy. This may be followed by biopsies and scans as appropriate. Screening (detection of cancers prior to symptoms) is effective for preventing and decreasing deaths from bowel cancer.
Treatment
Treatments used for colorectal cancer may include some combination of surgery, radiation therapy and chemotherapy. Cancers that are confined within the wall of the colon may be curable with surgery and various minimally invasive techniques are now available to reduce the impact of cancer surgery on patients.
All bowel cancers are discussed in the multidisciplinary team meeting (comprising of surgeon, oncologist, radiologist, pathologist and colorectal nurse practitioner) to individualise treatment plan according to disease and patient needs and wishes.