Bowel cancer is one of the most common forms of cancer in the UK. Sara Forrest explains how underwriters view this condition
Bowel cancer can occur anywhere in the colon or rectum. Cells lining the inside of the bowel are constantly dying and being replaced. A cancer arises when this process of renewal goes wrong. These abnormal cells can form a polyp and develop into cancer. If the cancer is not treated, cells can break away and spread to other parts of the body, often to the liver.
The majority (98%) of colorectal cancers are adenocarcinomas. Others are squamous cell carcinomas, carcinoid tumours, lymphomas and leiomyosarcomas.
Adenocarcinoma - These tumours start in the lining or internal skin layer of the bowel. They are the most common type of small bowel cancer and usually appear within the duodenum.
Carcinoid - Carcinoid tumours arise in the cells that make hormones in the small intestine. These tumours also appear more commonly in the ileum and sometimes within the appendix
Lymphoma - These tumours start in the lymph tissue of the small bowel. The lymph tissue is part of the body's immune system. Usually small bowel lymphomas are of the type known as non-Hodgkin's lymphoma, and appear more commonly in the jejunum or ileum.
Sarcoma - Leiomyosarcomas are sarcomas that usually grow in the muscle wall of the small bowel. These more commonly occur in the ileum. Another, rare type of sarcoma is gastrointestinal stromal tumour (GIST), which can develop in any part of the small bowel.
There are a number of risk factors associated with bowel cancer:
- Age. Bowel cancer can occur in younger people, but nine out of 10 people who get it are over the age of 50.
- A previous polyp or bowel cancer. Not all types of polyps increase the risk of bowel cancer, but adenomatous polyps do.
- Personal history of chronic bowel inflammation. Ulcerative colitis and Crohn's disease will slightly increase the risk of developing bowel cancer.
- Diet. A diet that is high in red meat and fat and low in vegetables, folate and fibre may increase the risk of bowel cancer.
- Exercise. Moderate exercise may help prevent colorectal cancer developing.
- Obesity. Being overweight or obese may increase the risk of bowel cancer developing.
- Smoking and alcohol. Although not as strong a risk factor as for other cancers, smoking may also increase the risk of bowel cancer, particularly in heavy drinkers. Alcohol consumption may increase risk, especially in those with low levels of folate in their diet.
- Family history. Less than one in 10 cases of bowel cancer are due to an inherited gene defect. However, there are certain families who have an increased risk of developing bowel cancer due to a variety of conditions including familial adenomatous polyposis (FAP) and hereditary non-polyposis colon cancer (HNPCC).
- Personal history of bowel cancer. Having had bowel cancer before increases the risk of a new cancer developing.
Symptoms may include:
- Blood (bright red or black flecks) or mucus in the stool (faeces).
- Changes in bowel habits. Diarrhoea, constipation or both, anything that is abnormal, or which lasts more than two weeks.
- The feeling of still having to go to the toilet even after having emptied the bowels.
- Pain or discomfort in the stomach area (colicky pain, cramps, or tenderness).
- Unexplained weight loss.
- Extreme tiredness (this may be due to bleeding).
- A lump in the abdomen.
Investigations to detect bowel cancer may include:
- Rectal examination - The doctor carries out an internal examination and feels for any lumps or swellings.
- Faecal occult blood test (stool test) - Chemical test that can pick up minute traces of blood in the faeces. The test is normally done by applying a small sample of faeces to a piece of paper that contains the reacting chemical. The paper changes colour if blood is present. This test is not completely reliable as bleeding bowel cancers do not bleed all the time, so if tested when the tumour is not bleeding, you will get a false negative result. Additionally, certain food and drinks can also cause a false negative result. Home testing kits are now available in the shops, although this is usually a hospital test.
- Sigmoidoscopy and proctoscopy - Tests to look inside the rectum (proctoscopy) or rectum and lower part of the large bowel (sigmoidoscopy). The bowel is inflated with air and a flexible tube with a light inside is passed into the rectum, a biopsy (sample of tissue) can be taken if necessary.
- Colonoscopy - This test looks at the whole of the inside of the large bowel. A flexible tube is passed into the rectum and up into the bowel. As the tube bends easily, it can pass around the curves in the bowel so it can examine the whole length of it. The light inside the tube helps to find any problem areas or swelling. Photographs and biopsies of the lining of the bowel can be taken during the test.
- Barium enema - This is an X-ray of the large bowel. The barium passes through the bowel and shows up any lumps or swellings.
The stage of a cancer is a term used to describe its size and whether it has spread beyond its original site. Knowing the particular histology (microscopic study of the structure, function and composition of the body tissues) and the stage of the cancer helps the doctors to decide on the most appropriate treatment.
Cancer can spread in the body, either in the bloodstream or through the lymphatic system. The lymphatic system is part of the body's defence against infection and disease. The system is made up of a network of lymph glands (also known as lymph nodes) that are linked by fine ducts containing lymph fluid. Doctors will usually check the lymph nodes close to the bowel in order to help determine the stage of the cancer.
Since 1932, bowel cancers have been staged according to the Dukes classification following surgery, but more recently there has been a preference to use the TNM classification:
Stage 1 - The cancer is contained within the lining of the bowel or has spread into the muscle wall, but has not begun to spread to the lymph nodes or other parts of the body.
Stage 2 - The cancer has spread through the muscle wall and may affect other nearby structures such as the pancreas.
Stage 3 - The cancer has spread to nearby lymph nodes.
Stage 4 - The cancer has spread to nearby lymph nodes and also to other parts of the body such as the liver or lungs.
The three main treatments for bowel cancer are:
Surgery - About four out of five patients undergo some form of surgery. It can be extremely successful. Generally, a specialist will remove the area of the cancer and a small amount of surrounding tissue.
Radiotherapy - Radiotherapy uses high-energy rays similar to X-rays to kill cancer cells.
Chemotherapy - Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. Occasionally chemotherapy may be given in combination with radiotherapy or surgery, or on its own, to treat cancer of the bowel. Chemotherapy is not suitable for every situation and its effectiveness in bowel cancer is still being researched.
The risk of developing bowel cancer is two or three times higher in people with a strong family history when compared to the general population. Strong family history means you have several relatives diagnosed with bowel cancer, or relatives diagnosed at a particularly young age. Examples of strong family history are:
- One first degree relative diagnosed before the age of 45.
- Two first degree relatives diagnosed with bowel cancer. A first degree relative is a parent, child or sibling. It is advisable that these relatives are screened by colonoscopy to detect any cancers or polyps at an early stage.
UNDERWRITING IMPLICATIONS
For most benefits, a tumour questionnaire will be requested from the client's GP. As with most cancers the terms will depend on the type and extent of the tumour, success of the treatment and length of time since initial treatment was completed. Initial treatment may combine surgery, chemotherapy and radiotherapy. Critical illness (CI) will be declined in all cases.
Our guidelines may allow us to offer terms for life and income protection (IP) with a temporary extra 'per mille rating' where an extra annual charge is applied per £1,000 of sum assured. Dependent on the staging of the cancer, we may not be able to offer terms for the first few years or in some instances it may incur a minimal permanent extra rating. IP can only be considered with a minimum deferred period of 13 weeks.
Where a client discloses a family history of bowel cancer a rating may apply. If the applicant is aged under 50 and has one first-degree relative diagnosed with bowel cancer before age 60 then a small permanent extra will apply for CI. All other benefits would be at standard rates.
In the case of two or more first degree relatives diagnosed with bowel cancer we would request a General Practitioner's Report from the client's GP and in most instances terms would be subject to a permanent extra rating.
Although if the client has been well followed up with regular negative colonoscopies, the last being last within two years, then we may be able to offer a credit on the normal rating imposed.
FACTS AND FIGURES
- Bowel cancer is the third most common cancer in men after prostate and lung cancer, accounting for 14% of all cancers; and the second most common cancer in women after breast cancer, accounting for 12% of all cancers.
- Bowel cancer caused 16,000 deaths in the UK in 2003. Mortality rates are higher in men than in women.
- Each year, there are 18,500 new cases of bowel cancer in men, and over 16,000 cases in women. In most people the cause is still unknown, but research is underway. Like most types of cancer, bowel cancer is more common in older people. It is unusual for bowel cancer to be diagnosed in people under 50.
- There have been significant improvements in five-year survival rates over the last thirty years for bowel and rectum cancers. For men diagnosed with colon cancer in the early 1970's the five-year survival was 22%. Men diagnosed in the late 1990's had a five-year survival of 47%. For women with colon cancer over the same time period the rates were 23% and 48%. Similarly, there was an improvement in the five-year survival for patient's diagnosed with rectum cancer. For men, five-year survival increased from 25% to 47%, and for women, 27% to 51%.
SOURCES:
www.cancerresearchuk.org
www.cancerbackup.org.uk
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