What Is Colorectal Cancer? 9 Important Tests Used To Diagnose Colon Cancer

Having a healthy colon is essential for digestion and waste removal in the body. When the colon does not function properly, the body cannot absorb essential nutrients or eliminate waste products.

What Is Colorectal Cancer?

Colorectal cancer is a type of cancer that begins in the colon or the rectum. Depending on where it begins, it is often referred to as either colon or rectal cancer. These two cancers have many similarities and are often grouped.

Colorectal cancer is often called colon cancer when colon cells grow out of control. The colon is the large intestine, and the rectum is the passageway that connects the colon to the abdomen.

Usually, colon cancer affects older individuals, although it can occur at any age. Polyps are small, noncancerous cells that grow inside the colon. However, some polyps may become cancerous over time [1][2].

What Are The Early Warning Signs Of Colon Cancer?

There are no symptoms in the early stages of colorectal cancer, so the condition can go undetected. However, once symptoms appear, they may vary depending on the location and size of the tumour.

Among the many signs of colon cancer changes in bowel habits, blood in your stool, abdominal discomfort, fatigue, weakness, or unexplained weight loss. Several diagnostic tests can diagnose this condition, but your doctor may select a test based on certain factors such as cancer type, signs and symptoms, medical and family history, age, and general health [3][4].

What Are The Diagnostic Tests For Colorectal Cancer?

Take a look at some of the different diagnostic tests for colorectal cancer [5][6][7]:

1. Biopsy test

As the only method for determining a definite diagnosis of colorectal cancer, a biopsy involves removing a small amount of tissue to be analysed under a microscope. This procedure may be performed during a colonoscopy or on any tissue removed during surgery. In some cases, a CT scan or ultrasound may be used to assist in the procedure.

2. Colonoscopy test

In a colonoscopy, a patient is sedated, and a complete view of the entire colon and rectum is taken. This is because Colorectal cancer diagnosis cannot be determined until the tumour has been surgically removed, which may result in a complete diagnosis which accurately describes cancer's location and spread.

3. Biomarker testing

Biomarker testing, also known as molecular testing of a tumour, may be recommended to identify specific genes, proteins, and other factors specific to the tumour. The results of these tests will help you determine the best course of treatment for you.

4. Computed tomography (CT) scan

With a computed tomography (CT) scan, X-rays take images of your insides from various angles. A computer then combines the images to indicate whether there are any abnormal tumours. The scan is often performed prior to surgery to determine whether cancer has spread to the lungs, liver, and other organs.

5. Magnetic resonance imaging (MRI)

A magnetic resonance imaging (MRI) test uses magnetic fields to create detailed images of the body. It can measure the tumour's size and is considered the best method of locating where colorectal cancer has spread.

6. Ultrasound

Ultrasounds are commonly used to determine how deeply rectal cancer has spread and to plan treatment. However, ultrasounds are inaccurate in detecting cancers that have spread beyond the pelvis and nearby lymph nodes.

7. Positron emission tomography (PET)

PET scans, or PET-CT scans, combine CT and PET scans. PET scans are used in specific situations and are not recommended for all patients suffering from colorectal cancer.

8. Chest x-ray

An x-ray of the chest can determine whether cancer has spread to the lungs.

9. Blood test

Often, colon cancer results in bleeding into the large intestine or the rectum. As a result, patients may become anaemic. Blood tests measure the number of red blood cells in the body, indicating whether bleeding is occurring. Nevertheless, it is not intended as a screening test for colorectal cancer but as a tool for treating patients suffering from this disease.

Who Are At Risk Of Colorectal Cancer?

Even though colon cancer can be diagnosed at any age, most patients are older than 50. In recent years, rates of colon cancer have increased in people younger than 50, but scientists do not know why. Compared with other races, African-Americans are at greater risk for colon cancer [8].

Is Colorectal Cancer Preventable?

By screening for colorectal cancer, precancerous polyps can be found and removed before they become cancerous. By doing so, colorectal cancer can be prevented. Screening can also identify colorectal cancer early when the chance of successful treatment is most significant [9].

How Is Colorectal Cancer Treated?

A colon cancer patient usually undergoes surgery to remove cancer, along with other treatments such as radiation therapy and chemotherapy [10].