Colorectal cancer is the second leading cause of cancer-related death and one of the most preventable. The lifetime probability of an average person developing colorectal cancer is 6% (or about one in 20). Over 35,000 patients are diagnosed and about 16,000 people in the UK die each year from bowel cancer.
WHO IS AT RISK OF COLORECTAL CANCER?
Although colorectal cancer may occur at any age, more than 90% -95% of these tumours occur in people over the age of 40. The risk increases with age; most people diagnosed with the disease are in their 60's or 70's. Certain factors are associated with higher risks including personal history of breast, uterine or ovarian cancer; inflammatory bowel disease (ulcerative or Crohn's colitis) or a family history of polyps or colorectal cancer.
HOW DOES IT START?
Most colon and rectal cancers develop from a single cell or group of cells in the lining of the bowel. These cells start to multiply and grow into a non-cancerous (benign) growth called a polyp. Polyps appear as elevations or projections on the lining of the bowel wall some are on a stalk rather like a mushroom.
The change of a benign polyp into a cancerous tumour appears to be associated with changes or mutations in the genes that control each cell.These changes may be inherited or may occur spontaneously.
WHAT ARE THE SYMPTOMS?
Many polyps and cancers of the colon and rectum do not produce symptoms until they become fairly large. It is important to try and find them when they are small and easily removable. Therefore, recommendations have been developed for the screening of people without symptoms to find these growths or polyps while they are small. The launch of bowel cancer screening in the UK began in 2007.
When symptoms occur, they may be attributed to other common disorders such as haemorrhoids. The most common symptom is bleeding with bowel movements (blood in the stool, toilet water, or on the toilet tissue). Changes in bowel habits, such as new problems with constipation or persistent diarrhoea are good reasons to see your doctor for evaluation. Abdominal pain and unexplained weight loss may be symptoms of more advanced cancers.
HOW CAN YOU PREVENT COLORECTAL CANCER?
Although colorectal polyps and cancers may not produce symptoms early in their development, simple screening methods can detect many growths or polyps early. Finding and removing colorectal polyps with colonoscopy clearly reduces the risk of their developing into cancers.
Diet plays a role, although how big a role is not clear. A diet high in fibre such as those found in whole grains, fruits and vegetables, and low in fats will likely reduce your overall risks of developing cancer. In addition, a high-fibre, low-fat diet will reduce the risk of heart disease, diverticular disease, constipation and haemorrhoids.
WHEN SHOULD YOU BE CHECKED FOR COLON AND RECTAL POLYPS?
Men and women who have one of the risk factors described earlier should be examined by their physician annually beginning at the age of 40 with a digital rectal examination and a test for blood in their stool. In addition, at age 50, a flexible sigmoidoscopy examination of the lower bowel should be performed. If normal, it should be repeated every five years.
Alternatively, average risk persons can be screened using a barium enema x-ray examination every five to ten years or colonoscopy every ten years. People with an increased risk for colon and rectal growths should have the entire colon and rectum examined.
A colonoscopy is usually the best method, but sometimes a barium enema x-ray combined with a flexible sigmoidoscopy exam will suffice. Generally, this should be repeated every five years. The timing of the first exam depends on the risk factors present. If one or more family members have had a colon or rectal cancer before the age of 50, screening should start at age 40 (or five years younger than the age at which the diagnosis was made). If one parent has familial polyposis, screening should start at age 12-14. Screening in individuals with other risks such as inflammatory bowel disease (Crohn's disease or ulcerative colitis), should be discussed with your doctor.
People who have a family history of colorectal cancer or polyps or a personal history of colorectal cancer or adenomatous polyps should have a colonoscopy. Any polyp should be removed and the examination repeated in one to three years. If the exam is normal, then colonoscopy should be repeated every three to five years. Women with a personal history of breast, ovarian or uterine cancer should also have colonoscopy every three to five years beginning at age 40.
OW DOES COLORECTAL CANCER SPREAD?
Cancer has two ways of spreading: by direct growth of the tumour through the bowel wall and into adjacent tissues and by distant spread cancerous cells called metastases most commonly to the liver or the lungs.
Direct growth: As these tumours grow, they may spread into or around the bowel. Eventually, they will invade the bowel wall and spread into adjacent organs, such as/cther loops of intestine, the abdominal wall the bladder, or the uterus.
Metastases: Clumps of cells may break off from the primary tumour and spread to other parts of the body through the blood stream or through the lymph fluid that bathes the cells. These cells may then attach and grow at distant sites such as the lymph nodes around the bowel, the liver, or the lungs.
When a colorectal cancer is surgically removed, the lymph nodes in the tissue around the tumour are also removed.The pathologist then looks at the nodes under a microscope to see if they contain any tumour cells.If there are no tumour cells in the lymph nodes, chances for a cure are better.
HOW ARE CANCERS OF THE COLON AND RECTUM TREATED?
These cancers are removed surgically. An operation is usually performed through an abdominal incision or through four or five small incisions if done by keyhole surgery. The section of bowel containing the cancer along with the associated blood vessels and lymph nodes are removed.
In most cases, the bowel is put back together or rejoined so that normal bowel function is restored. This reconnection is called an "anastomosis." If the cancer has spread to the lymph nodes or elsewhere, additional (adjuvant) treatment such as chemotherapy and/or radiotherapy may be suggested.
Cancers of the rectum develop in the lower six inches of the large bowel above the anus. There are more options for treating these tumours. Most are also removed surgically. Larger, non cancerous polyps and some early cancers may be removed through the anus. Most of the larger cancers are removed surgically through the abdomen.
Although the bowel is usually rejoined after surgery, removal of the entire rectum and anus may be occasionally necessary when the cancer is located very close to the anal opening. In this situation, a colostomy is created. This is an opening of the bowel through the skin of the abdominal wall. In rare instances, a temporary colostomy may be required if the cancer blocks the bowel. Today, most colorectal cancers can be treated without a colostomy.
Additional treatment for rectal cancers includes radiation therapy and or chemotherapy. Usually this additional therapy is given prior to the main operation as research has shown this is the best way of treatment.
WHAT IS "STAGING" AND WHY IS IT IMPORTANT?
Staging provides a way to estimate the chance of a cure after a cancer has been removed. Unlike other solid tumours, the size of the colorectal cancer has little influence on the possibility of cure. A staging system helps the doctor evaluate the tumour based on: if it has grown into the bowel wall; if it has spread into nearby lymph nodes; and, if it has spread to distant organs or tissues.
Tumours are classified in the UK as Dukes A, B, C, or D: Staging is important because it can help predict chances of survival and guide additional treatments.
If a colorectal cancer recurs, it will usually do so within two years of surgery. The vast majority recur within five years. The best chances for a cure, or the best outcome is associated with Dukes A cancers with more than 90% of these patients surviving five years after surgery.
WHAT IS THE LONG-TERM OUTCOME AFTER TREATMENT?
Estimates of long-term cure are based on the stage of the disease. Patients with early cancers, which have not grown through the bowel wall and have not spread to the lymph nodes or elsewhere, have an excellent outlook.
When the cancer has spread to other areas or involves the lymph nodes, the chance for cure may be significantly improved by additional surgery and/or chemotherapy or radiation therapy.
The key to preventing or curing colorectal cancer is to detect it early by undergoing appropriate screening and, when found, removing polyps. Early detection of cancers with prompt treatment will also result in a high cure rate.
If you wish to arrange an appointment with Mr. Rob Church contact your GP.
Or Contact Jacque 0782 6559444
Or the Hospital of your choice:
Spire Hospital Little Aston
Nuffield Hospital Wolverhampton
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