Bowel cancer, also known as colorectal cancer, forms in the tissues of the colon or rectum.
This is a common type of cancer and is one of the leading causes of cancer deaths in the UK, but with early detection and treatment, it is highly curable.
The delayed onset of symptoms often leads to an advanced stage diagnosis. Regular screening can assist in catching the signs earlier and getting ahead of this serious disease.
What Is Bowel Cancer?
Bowel cancer begins in the large bowel or intestine, including the colon (which is divided into ascending, transverse, descending and sigmoid colon) and the rectum. These abnormal cells can form a tumour, leading to various complications if left untreated.
The large bowel is part of the digestive system, absorbing water from undigested food in the colon, and storing the remaining waste in the rectum before it is passed out of the body.
Bowel cancer is one of the top 5 most common cancers in the UK, and is the second biggest cause of cancer deaths. However, each person’s journey with bowel cancer will be different, as every person’s body, medical history, health, and treatment response is different.
Who Is At Risk Of Bowel Cancer?
While we are not yet certain of what causes bowel cancer, there are several known factors that influence your risk of bowel cancer.
As we age, the genetic changes due to our environment, lifestyle, and errors in normal cell processes accumulate, and our biological defence mechanisms are less efficient at getting rid of mutations that lead to the uncontrolled growth of cancer cells. This means that the older we get the higher our risk of developing cancer, with most cases of bowel cancer occurring in patients over the age of 50.
However, bowel cancer can still be diagnosed in younger patients and these numbers appear to be rising. It is important that all ages be aware of the risks and on the lookout for symptoms.
Individuals with a family history of bowel cancer are at a higher risk, particularly if you have close relatives (parents or siblings) who have been diagnosed under the age of 50, or multiple relatives with a history of bowel cancer.
Certain genetic conditions, such as Lynch syndrome or Familial Adenomatous Polyposis (FAP), can increase the risk. If someone in your family has been diagnosed with one of these conditions, talk to your doctor about screening for genetic testing.
An unhealthy lifestyle, including a poor diet, lack of exercise, obesity, smoking, and alcohol consumption, can also contribute to an increased risk. If you have inflammatory bowel disease (including Crohn’s disease and ulcerative colitis), type 2 diabetes, or bowel polyps (small growths), you may be at a higher risk of developing bowel cancer.
What Are The Symptoms Of Bowel Cancer?
There are several symptoms that could indicate bowel cancer. While bowel cancer symptoms are often only noticeable when the cancer has reached a more advanced stage, some of these problems could present in a mild form earlier on in the course of the disease.
While other health problems can also cause these symptoms, it is important that you keep an eye on any changes and consult with your doctor as soon as possible if you do notice anything new.
Some may find these issues embarrassing to discuss, but if you are dealing with bowel cancer an early diagnosis is essential to improved outcomes, and doctors are well accustomed to dealing with bodily functions.
- Changes in bowel habits: Onset of diarrhoea or constipation, or a noticeable change in the size and shape of stools, particularly thin stools. It may also seem that the bowel is not fully emptying.
- Blood in the stool or rectum: Bright red or dark-coloured blood in the stool, or bleeding from your bottom. While haemorrhoids can also produce these symptoms, they usually come and go with flare-ups, while rectal bleeding from cancer is more likely to continue and can be accompanied by pain. Monitor for any signs of iron-deficiency or anaemia, which could also indicate intestinal bleeding.
- Abdominal discomfort: Cramps, bloating, or pain in the abdomen, or even nausea or vomiting.
- Unexplained weight loss: Unexplained weight loss without any dietary or lifestyle changes.
- Fatigue and weakness: Generalised tiredness and weakness, even without any physical exertion.
How Is Bowel Cancer Diagnosed?
Generally speaking, bowel cancers that are diagnosed and treated at an early stage have high survival rates, while bowel cancers diagnosed at advanced stages have low survival rates. Regular screening tests can help detect bowel cancer at an early stage when it is most treatable.
If you experience symptoms or changes, your doctor might do a physical exam of the stomach and rectal area, and you may need to provide a stool sample. If symptoms or results are concerning, further investigation will then be needed.
Screening tests are done in the absence of symptoms, and are one of the best ways to reduce bowel cancer mortality, as the symptoms connected to the disease often present when the cancer is already more advanced. If the screening test is abnormal, you will require further diagnostic testing, such as a biopsy, which can be done during a colonoscopy.
Common screening methods include: Colonoscopy, which examines the entire colon and rectum using a colonoscope; Sigmoidoscopy, where only the rectum and sigmoid colon are examined; CT colonoscopy, often used as a radiological option if the patient is medically unfit for colonoscopy; Stool tests such as faecal occult blood tests (FOBT) or faecal immunochemical test (FIT), which detect hidden blood in the stool; and stool DNA tests.
It is generally recommended that individuals aged 50 and above undergo regular screening, and in the UK older populations may be provided at-home FIT tests by the NHS.
How Is Bowel Cancer Treated?
The treatment for bowel cancer depends on the stage and extent of the disease, your age and overall health, whether certain genetic changes are present, and where the cancer is located (colon, rectum, or both).
Common treatment options include surgery, chemotherapy, radiation therapy, and targeted drug therapies. These therapies can be used in combination to increase the efficiency of a treatment or prevent recurrence.
Surgery is a common bowel cancer treatment, and could include a local excision for early stage cancer that is confined to a small area, or a colectomy, which involves partial or full removal of the bowel. Nearby lymph nodes are usually also removed and tested. Advanced colon cancer often spreads to the liver and lungs, which means that a liver or lung resection may be needed.
Depending on the extent of the surgery, a temporary or permanent stoma may be required. A stoma is an opening in the abdominal wall through which stool passes into a disposable bag instead of going through the rectum and anus. If you have a bowel obstruction, surgery could also be used to remove the blockage or insert a stent (thin metal tube).
Chemotherapy can be used before surgery to shrink the tumour (neoadjuvant therapy), after surgery to prevent recurrence (adjuvant therapy), as an alternative to surgery, or to manage symptoms of advanced bowel cancer (palliative therapy). Radiotherapy may be appropriate for rectal cancer or if the cancer has spread, and targeted therapies or immunotherapy may be appropriate for advanced bowel cancer if certain genetic changes are present.
Treatments can have side effects, whether during treatment or some time after completion. These include: fatigue; hernias; nerve damage; and changes in bowel, sexual and bladder function.
Can You Prevent Bowel Cancer?
While not all cases of bowel cancer can be prevented, there are several lifestyle changes that can help reduce your risk. These include: A healthy diet, rich in fruits, vegetables, whole grains, and low in processed foods, red meat, and saturated fats; regular physical activity; avoiding obesity and maintaining a healthy body weight; quitting smoking and limiting alcohol consumption.
If you are older, or have an increased risk of the disease due to family history or other factors mentioned earlier, it is recommended that you get regular bowel cancer screening. However, even if you do get regular screening cancer could develop in between, so make sure to be alert to the symptoms mentioned above.
Screening could also reveal polyps. Not all polyps will develop into cancer, however if your polyps are found to be precancerous, your doctor may advise a colonoscopy procedure to remove them.
Can I Beat Bowel Cancer?
Bowel cancer is the second deadliest cancer and a significant health concern worldwide. However, all hope is not lost as statistics are improving and timely intervention can lead to effective treatment.
Waste, or poo, may not be a comfortable topic for polite conversation, but it is important to understand the essential waste-removal process that our body undergoes, as well as the diseases that can affect this efficient process. Understanding the risk factors, recognising the symptoms, undergoing regular screening, and adopting a healthy lifestyle are essential steps towards reducing the burden of bowel cancer.