Colon cancer is the fourth most common cancer in the UK after breast, prostate and lung
cancer with over 40,000 new diagnoses in the UK every year. It will affect 1 in 14 men
and 1 in 19 women during their lifetime with the vast majority being over the age of 50.
Cancer of the colon and rectum is a process where the natural control mechanisms of cell
proliferation are lost through a series of genetic mutations leading to uncontrolled
cell division. The majority of cancer is within the large bowel, start their lives as small
polyps measuring only 1mm in diameter and then gradually enlarge in size over the next
5 to 10 years ultimately turning into cancer through genetic mutation.
Benign polyps can easily be diagnosed during routine diagnostic colonoscopy which is the
fiber optic examination of the large bowel when they can be removed and at the same time
removing the risk of bowel cancer.
The symptoms of colorectal cancer tend notto arise until the tumor has reached a significant, critical size and small cancers and pre-malignant
polyps are completely symptom free. The key thing here is acting quickly when symptoms
arise and early investigation because the earlier a tumor is identified, the earlier
the stage of the cancer, the more likely it is the cancer will be curable. Like all tumor
types, prevention is better than cure. The common symptoms of bowel cancer include
bleeding from the bottom either fresh blood on the toilet paper or in the toilet. Any
change in the bowel habit from the norm including looser stool or an increase frequency of stool
or a deterioration and constipation will be of concern. Abdominal pain out of the ordinary
or weight loss are also worrying features. Finally, if the general practitioner has done
some blood tests, any iron deficiency anemia suggests chronic blood loss from the gut.
The latest surgical techniques are minimally invasive surgical techniques. For example,
during a colonoscopy, which is the fiber optic examination of the bowel, polyps are routinely
removed and some of these larger polyps may contain a very early cancer. And in these
patients, that polyp removal may be the only treatment the patient needs but with no requirement
of surgery. Also in a small percentage of patients, perhaps
less than 5% of patients with rectal cancer, if the tumour is very early, it can be removed
trans-anally, in other words, through the bottom without the need for removal of a large
segment of colon. That again is considered to be minimally invasive.
But for the vast majority of patients, the affected segment of bowel will need to be
removed surgically. The big advance in the last 15 years has been with the advent of
keyhole surgery or laparascopic surgery where the bowel is removed with tiny cuts, much
less post-operative pain and therefore a quicker return to normal activities and back to work
quicker. There’s obviously a cosmetic component to that as well opposed to traditional open
surgery where there would have been a large midline scar with a more painful recovery.
As we’ve touched on earlier, prevention is better than cure for any cancer type including
colorectal cancer. The NHS screening program has been very comprehensive in its screening
for colon cancer and it is two-fold. The first method of screening in the UK is
with Fecal Occult Blood Testing Kits. These kits are sent out to the patient’s home
address between the age of 60 and 74 very two years. The kit comes with instructions
as to how to apply a small stool sample onto the kit. The kit is then sent back to the
central laboratories and it analyzes for small invisible amounts of blood within the stool
which is what colorectal cancer will produce. The second type of bowel screening in the
UK is known as Bowel Scope where patients aged 55 are invited to come along for a one
off fiber optic camera examination of the lowest part of the colon. It’s a relatively
easy procedure that takes about five or ten minutes and for every 300 people screened,
it’s thought that two will be prevented from developing bowel cancer and one life
saved from bowel cancer.