Colorectal Cancer: Symptoms, Diagnosis, Treatment & Prevention

Dr.Arun Giri, 5 mins read

Colorectal cancer, also known as colon cancer and rectal cancer, is a type of cancer that starts in the large intestine (colon) or rectum. It can also spread to other parts of the body through lymph nodes. Usually, it begins as small, noncancerous clumps of cells called polyps. Although it can occur at any age, it usually affects elderly people. With time, these polyps can turn into colon cancer. 

That’s why healthcare providers often recommend a screening test that can detect precancerous cells before they turn into colon cancers.

Symptoms

In the initial stage of cancer, some people may not notice symptoms. When the symptoms start appearing, they’ll likely vary based on the tumour’s size and location in the colon. 

• Fatigue
• Unexplained weight loss
• Blood in stool or rectal bleeding
• Feeling shortness of breath
• Abdominal discomfort
• Persistent change in bowel habits
• Vomiting
• Anemia

Causes

Experts are not sure what exactly causes most colon cancers. But doctors believe that when the DNA of the cells present in the colon mutates, the DNA starts giving wrong instructions to cells. As a result, cells begin multiplying uncontrollably and form a tumour.  

Diagnosis

If you have symptoms related to colon cancer, your doctor will recommend any or all of the following tests:

• Colonoscopy: In this test, a long, slender and flexible tube equipped with a camera is used to see the entire colon and rectum. If the doctor finds any suspicious area, he will pass surgical tools through the tubes to take a sample of the cells for biopsy.
• Blood test: Although blood tests don’t tell directly about colon cancer, it helps in knowing about the overall health, like liver and kidney function tests. The test also helps to know the level of a chemical sometimes produced by colon cancer called a carcinoembryonic antigen, or CEA. The level of CEA helps doctors understand your prognosis and whether your cancer is responding to the treatment

If the doctor suspects colon cancer, he will prescribe staging tests, which include a CT scan. The stages of colon cancer are identified by Roman numerals that range from 0 to IV. IV indicates cancer has spread to other body parts. However, in some cases, the stage of colon cancer is difficult to determine until after surgery.

Treatment

Treatment of colon cancer depends on your situation and the tumour’s size, location and stage. The main goal of treatment is to remove the tumour - stop its spread and reduce any uncomfortable symptoms. Based on your specific condition, the doctor may recommend a treatment option.

• Surgery - Usually, it is considered a preferred treatment option for early-stage cancer. If the cancer is only present in a polyp, people may require a polypectomy procedure to remove it. Your doctor may also go for a colectomy. 
• Radiation Therapy - The doctor uses high-energy gamma rays to kill cancer cells. The doctor can also implant a radioactive material in the form of a seed near the cancer site. Radiation therapy helps shrink a tumour and destroy cancer cells. It can also be used with other cancer treatments.
• Chemotherapy - The medical professional will administer medications that target any rapidly dividing cells. A doctor usually recommends chemotherapy to:
  1. Shrink the size of the tumour before surgery for easier removal 
  2. Kill the left cancer cells after the surgery

During this process, the doctor removes a part of the colon that contains cancers and its surrounding area. Then the doctor either reattaches the healthy part of the colon or opts for a stoma, a surgical opening in the wall of the abdomen through which waste directly passes into a bag. Thereby removing the need for a colon. This process is called a colostomy. 

Apart from this, your doctor may recommend:

• Endoscopy: The doctor uses a long, flexible tube equipped with a camera, light and surgical tools to remove the small, localised cancers. 
• Palliative surgery: This option is usually used in case of advanced or untreatable cancer. Through this procedure, the doctor attempts to manage pain, bleeding and other symptoms. 
• Laparoscopic surgery: The doctor may make small incisions in the abdomen to remove cancer or large polyps.

Prevention

• Limit alcohol intake
• Quit smoking
• Maintain a healthy weight
• Consider regular exercise
• Eat a variety of vegetables, fruits and whole grains

Get a screening for colon cancer:

You should consider periodic screening tests for early diagnosis. If you have a family history of colon cancer, you should actively go for screening.

Also, Read: World Cancer Day