90% of colorectal cancer cases have a high success rate if they are diagnosed in time.

In this article, we're going to tell you what you need to know when it comes to colorectal cancer screening.


What is colorectal cancer?

Colorectal cancer, also known as CRC refers to the abnormal growth of cancerous cells on the large intestine and rectum. Colorectal cancer is known as colon cancer in the US and bowel cancer in Europe.

Colorectal cancer generally affects those that are over the age of 45, however in recent years, there has been a rise in the incidence of colorectal cancer among younger demographics.

Colorectal cancer is the third most common cancer diagnosed in both men and women each year in the United States, excluding skin cancer. It is the second leading cause of cancer related death in the United States for men and women combined.

What Are The Symptoms Of Colorectal Cancer?

The symptoms of colorectal cancer may mimic commonplace side effects of everyday life including feeling tired all the time, digestive discomfort, bloating and gas, however if these symptoms persist, you need to get checked.

Some of the most common symptoms associated with colorectal cancer include:

  • A persistent change in bowel habits
  • Blood in your stool
  • Unexplained weight loss
  • Feeling tired all of the time

A persistent change in bowel habits
Changes in bowel habits may include constipation, diarrhea or a change in the texture of your stool lasting for four weeks or longer.

Blood in your stool
Blood in your stool may occur due to tumour bleeds, generally speaking tumours will not bleed alot and the bleeding will be on and off, so this may only show in fecal immunochemical tests.

Unexplained weight loss
Unintentional and inexplicable weight loss of upto ten pounds in six months may indicate a number of cancers, cancer cells can release substances that change the way food is converted to energy in the body. Cancer cells may also use the majority of the body’s energy supply as all systems in the body try to combat the disease.

Feeling tired all of the time
Rectal bleeding or finding blood in your stool may cause anemia, or an iron deficiency which can explain why you may feel tired all of the time coupled with your body's internal battle with cancer cells.


How do you screen for colorectal cancer?

There are a number of ways to test for colorectal cancer including tests that examine the stool for cancer cells and genetic material, procedures that involve an internal examination of the rectum and intestine, and finally imaging technology.

Let's go through the different methods to screen for colorectal cancer.

Colorectal Cancer Screening Using Stool Samples

Fecal Immunochemical Tests (FIT) take a swab sample from stool to detect blood that may not be visible to the naked eye. Blood in the stool and rectal bleeding are common symptoms of colorectal cancer. FIT tests can detect blood that has been secreted from the lower intestines in the faeces. This type of testing does not offer a definite answer of whether or not you have colon or colorectal cancer, however it offers an indication of whether or not you should seek out further testing. If you are experiencing early symptoms associated with colorectal cancer, consider taking a FIT test. If blood is detected in the stool, you may need to undertake a digital rectal examination (DRE).

  • Stool DNA Tests

Stool DNA Tests use DNA taken from a stool sample to determine whether or not one should get a colonoscopy by examining changes in DNA.

Colorectal Cancer Screening Using Internal Examinations

  • Colonoscopy

During a colonoscopy, a lighted tube called a colonoscope is inserted into the rectum while the patient is sedated. Using this method, a physician can examine the entire rectum for tumours, also known as polyps that may be benign or malignant. During a colonoscopy, a physician may remove polyps for a biopsy, in which the tissue is tested for cancer cells.

  • Sigmoidoscopy

During a sigmoidoscopy, a lighted tube is inserted into the rectum and lower colon in the same way a colonscope is while a patient is sedated. During this examination, it is not possible to check the upper intestine. Polyps can be removed for a biopsy in this test however, if there are cancerous tissues found, a colonoscopy is then recommended, indicating that it may be more effective to undertake a colonoscopy in the first instance.

Colorectal Cancer Screening Using Imaging Technology

  • Double Contrast Barium Enema (DCBE)

DCBE testing is used for patients who cannot receive anesthesia, or for those who cannot undergo a colonoscopy. During this test, x-rays are taken of the colon and rectum. This form of colorectal screening is usually not recommended by doctors as it cannot identify pre-cancerous cells.

  • Computed Tomography (CT/CAT Scans)

CT/CAT scans work in a similar way to a colonoscopy, however, in this instance, a radiologist works to find polyps through the x-ray images as opposed to physically searching with a colonscope. This is an alternative for those who cannot receive anesthesia.

What are the recommended screening ages for colorectal cancer?

Recommended screening ages for colorectal cancer vary from country to country.

Previously, the recommended age for screening in the U.S was between 50 and 75. Today Japan has the lowest recommended colorectal cancer screening age at 40 years, while Finland and Iceland have the highest recommended screening age at 60 years and over.

LetsGetChecked recommend following the screening guidelines from the American Cancer Society who encourage annual colorectal cancer screenings from the age of 45, and younger if you have a family history of colorectal cancer.

The American Cancer Society found that a dramatic increase in the number of colorectal cancer cases reported by young adults.


Have you ever attended a colorectal cancer screening? With LetsGetChecked, you can get the screening process started with a fecal immunochemical test that can detect the presence of blood in the stool. Receive your results within one week, with ongoing clinical support at every step of the way.

Written by Hannah Kingston | Approved by Medical Director, Dr. Dominic Rowley