Seeing blood in your stool is startling and unnerving. Many times, it’s caused by something relatively minor, such as peptic ulcers. However, sometimes it’s a sign of something more serious, such as colorectal cancer. Knowing more about this kind of cancer and what symptoms to watch for can help you reduce your risk or detect the problem early when it’s easier to treat. Dr. Graham Gibb, a general and colorectal surgeon, provides a brief overview of colorectal cancer.
What is Colorectal Cancer?
Colorectal cancer is cancer that begins in either the colon or rectum. It’s possible to divide this type of cancer into colon cancer, which begins in the colon, and rectal cancer, which begins in the rectum. They are often put together because they share common features.
The colon and rectum together form the large intestine, which is the lower part of your digestive tract. They are responsible for absorbing water and salt from the food matter that remains after it passes through the small intestine, then storing the leftover waste matter until it’s eliminated.
Colorectal Cancer Beginnings
A small growth or polyp on the lining of the rectum or colon is often the way colorectal cancer begins. Many of these polyps never become cancer, and the ones that do often take a few years to turn into colorectal cancer. This slow period of initial growth makes it possible to catch the cancer early, improving the likelihood of recovery. Certain polyp characteristics indicate a higher probability of developing colorectal cancer:
- Type – Polyps known as adenomatous polyps have a higher chance of turning into cancer than other kinds of polyps.
- Number – Developing two or more polyps puts you at a higher cancer risk.
- Size – Larger polyps, bigger than 1 cm, are more concerning than smaller ones.
- Dysplasia – Cells that appear abnormal but aren’t cancerous are called dysplasia; although not cancerous, they do tend to indicate a higher chance of developing cancer.
Stages of Colorectal Cancer
Like most cancers, colorectal cancer moves through stages as it develops; determining the stage of the cancer helps doctors treat it more effectively. Colorectal cancer has four stages:
- Stage 1 – In the initial stage, the cancer reaches only the lining of the colon or rectum.
- Stage 2 – By the second stage, it moves into the walls of the colon or rectum.
- Stage 3 – The third stage begins when the cancer penetrates nearby lymph nodes.
- Stage 4 – In the final stage, the cancer moves to other areas of the body.
Risk Factors You Can’t Control
There are a variety of risk factors that make a person more likely to get colorectal cancer. Some are things you can change, and others are not. Having some or all of these risk factors doesn’t mean you’ll develop cancer and not having any doesn’t mean you won’t, but you are at higher risk if you have many risk factors. The following are common risk factors for colorectal cancer that you can’t control:
- Being over 50 years of age
- A family history of colorectal polyps or cancer
- A personal history of colorectal polyps or inflammatory bowel disease
- Certain inherited syndromes, like Lynch syndrome and familial adenomatous polyposis
- Type 2 diabetes
- Being of Eastern European Jewish or African-American descent
Lifestyle Risk Factors
Other risk factors relate to lifestyle, and you can change these to lower your risk of developing cancer. Lifestyle risk factors include:
- Being overweight or obese
- Physical inactivity
- Certain kinds of diets, such as those high in processed or red meats
- Heavy alcohol use
Preventing Colorectal Cancer
Completely preventing colorectal cancer is impossible, but there are things you can do to reduce your risk of developing the disease. There are two main ways to help prevent colorectal cancer: screenings and controlling risk factors. Routine screenings are a key part of prevention. Polyps take time to develop into cancer, so screenings often discover and remove them before they have a chance to change into cancer. Controlling lifestyle risk factors is also important. Managing your weight, engaging in regular physical activity, eating a well-balanced diet, limiting alcohol to moderate amounts, and not smoking all help put you at a lower risk for colorectal cancer.
What are the Symptoms of Colorectal Cancer?
It’s difficult to discover colorectal cancer based on the signs and symptoms alone. Sometimes a person with cancer doesn’t display any symptoms, and many of the symptoms could also point to a different condition. That said, it’s still important to know some of the common signs and symptoms. Talk to your doctor if you notice any of the following symptoms of colorectal cancer:
- Constipation, diarrhea, or other change in bowel habits that lasts longer than a few days
- Blood in the stool
- Rectal bleeding
- Stool color change
- Passing excessive gas
- An urge to have a bowel movement that doesn’t go away after having one
- Weakness and fatigue
- Abdominal pain, cramping, or bloating
- Unexplained anemia
- Unexpected weight loss
The Importance of Routine Screening
Because signs and symptoms are unreliable indicators of colorectal cancer, routine screenings are the best way to catch the disease early. Early detection provides the best chance for effective treatment and recovery. Doctors recommend that people start getting regular screenings at age 50, but higher risk individuals may benefit from starting routine screenings at a younger age. A colonoscopy is a common and well-known screening test for colorectal cancer, but there are other tests as well. Screening tests include the following:
- Colonoscopy – Doctors insert a long tube with a camera attached into the colon and rectum to examine the area.
- Blood tests – Not actually a screening test for colorectal cancer, but blood tests can still be helpful in determining the presence of the disease because they help rule out other disorders.
- X-ray – Injecting barium into the colon and rectum coats the lining of the large intestine, making it visible in an x-ray.
- CT scan – Sometimes called a virtual colonoscopy because CT scans provide a detailed view of the colon.
Colorectal Cancer Treatment Options
Treatment options vary depending on what stage colorectal cancer is in when discovered. This kind of cancer is highly treatable when detected early, but recovery rates drop as the disease progresses. Doctors may recommend one or more treatment options based on the stage of the cancer. Treatment often includes surgery, chemotherapy, radiation, and medication.
Cancer is a serious disease, and colorectal cancer is no exception. Thankfully, by controlling risk factors and getting routine screenings, you can increase the likelihood of early detection and lower your risk of developing colorectal cancer in the first place.
About Dr. Graham Gibb:
Dr. Graham Gibb has been a practicing surgeon for 18 years. He received specialized training in colorectal surgery from the University of Texas and completed his postgraduate work in general surgery in Calgary, Alberta. When he can get away from the hospital, Dr. Gibb loves taking advantage of his new pilot’s license and take in the beautiful scenery in Peterborough, Ontario.
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