Q) I have a family history of colorectal cancer. What should I know about it and have there been any new breakthroughs?
A) Colorectal cancer is in fact two different types of cancer. It is a cancer (i.e. a disease where our cells grow too quickly and do not fully develop which results in a mass of cells known as a tumor) that can be found in the rectum or the colon depending upon where they started from.
They are often grouped together when we talk about them because they share so many features. Collectively they are deemed the fourth most commonly diagnosed cancer in Canada in 2022. It is the second leading cause of death from cancer in men (1 in 34 will die from it) and the third leading cause in women (in whom, over a lifetime it will be the cause of death in about 1 in 40).
It is estimated that in 2022, 5,200 men will die from it along with 4,200 women in Canada alone. On average, 67 Canadians will be diagnosed with it everyday and in those same 24 hours, 26 will die from it. These are sobering statistics, but not all of the news is bad.
The rate of new cases of colorectal cancer is declining in both sexes. This is more than likely due to increased screening which allows for early detection and the removal of precancerous polyps. Death rates have also been in decline for years now due to this same trend of earlier diagnosis coupled along with improved treatments. Regular screening is critical as many of these cancers might be present without any signs or symptoms.
The best screening tool we have is a colonoscopy in which a physician uses a long and flexible scope to view the rectum and the entire colon (after the patient has had their intestines emptied via fasting and the consumption of one of the various concoctions that force one to stay “close to home” the day before). Since it is a somewhat invasive procedure and requires the use of an operating room, this test is reserved for those at higher risk. For the rest of us, a fecal occult blood test that can be performed at home and sent to a lab is an adequate first step in screening. This test is designed to look for traces of blood (usually invisible to the eye) in our stools and results that appear abnormal or inconclusive can then trigger a colonoscope as a follow-up.
An exciting development in screening was just announced a few weeks ago. Researchers have developed a simple blood test that looks for four specific pieces of RNA (genetic) that, when detected together in higher levels, provide an extremely accurate indicator of even very early onset colorectal cancer. The test is inexpensive, requires only a small blood sample and could very easily someday be incorporated into a part of our routine annual healthcare given the high prevalence of this awful disease.
This is all great but the reality of healthcare right now is that routine screening does not always get done, especially in those who lack a family doctor or who choose only to make an appointment after the “wheels” have fallen off. As such, it would be wise to go over some of the common signs of colorectal cancer if/when they do finally start to appear.
These can include:
· A change in bowel habits- either constipation, diarrhea or incomplete evacuation (these are usually a sign of other less serious problems however)
· Blood in the stool (which can make it appear black or red)
· Unexplained weight loss
· Abdominal or pelvic pain
· Anemia (where you may be sluggish, short of breath and pale in colour)
With a disease as common as colorectal cancer, it would not be overstating the case to say that everyone is at risk from it. But of course, as with every other disease, there are some of us who have an increased chance of being diagnosed with this. These risk factors include:
- Personal history of colorectal cancer- unfortunately, just because you have already had it once doesn’t mean you aren’t more likely than other people to “get it” again
- Family history- this type of cancer can run in some families who have inherited a mutation in a cancer causing gene
- Age- while it can be diagnosed at any age, it is more common in those over the age of 50
- Other medical conditions- people who have type 2 diabetes, any of the inflammatory bowel conditions (such as colitis or Crohn’s), other types of cancer and certain inherited conditions among other diseases
- Lifestyle factors- smokers, the consumption of alcohol, the sedentary, and the overweight are all at an increased risk.
In fact, new research has shown just how a “western-style” diet might be helping to cause colorectal cancer. Diets termed as such are high in the consumption of red and processed meats (such as hot dogs, lunch meat slices…), sugar and refined grains (such as processed cereals, white flour products…) while also being low in vegetables and legumes. This type of diet seems to cause inflammation within the intestine (and elsewhere) which appears to play a role in the proliferation of a type of bacteria called pks+ E. coli, a subspecies of a bacteria that needs no introduction to those of us who have lived in this region for a few decades. This bacteria has recently been found to cause mutations in the DNA within cells of our colon providing a possible pathway that investigators can hopefully explore to find new and improved treatments or prevention strategies in “at risk” patients.
This list of those of us who are at risk due to our lifestyle choices is a lengthy one, which is a bit of a drag to be sure. The good news on that front, is that we use the term “choices” for a reason. For more information about this or any other health related questions, contact your pharmacist.