colon cancer

All You Need To Know About Colonoscopy

Dr. Prasenjit Chatterjee
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A colonoscopy is a process where a doctor uses a colonoscope to find cancerous and precancerous growth in colon. Colonoscopy shows ulcers, polyps and investigates the cause of rectal bleeding and abdominal pain. Learn more about the method and what should be done before and after a colonoscopy.

Colonoscopy is a procedure to look inside large intestine to detect possible signs of colon cancer. A long flexible tube with a camera and a source of light is inserted into the rectum, which allows the doctor to view the insides of the entire colon. They investigate the causes of blood found in stool, diarrhea or when an abnormality is found in a colonic X- ray computerized axial tomography (CT) scan. Colonoscopy is also used to prevent or remove abnormal growths, called polyps before they transform into cancer. Usually, colonoscopy allows accurate diagnosis and treatment without the need to go for a major operation. It is estimated in studies that through colonoscopy screening 76 to 90 percent of colon cancer can be prevented.

Colonoscopy Screening

When Does A Doctor Uses Colonoscopy?

A colonoscopy is recommended for the following reasons:

  • For investigating intestinal signs and symptoms like bleeding from anus, pain in abdomen, anemia, changes in bowel activity, such as diarrhea, unexplained weight loss.
  • Doctors also use colonoscopy as a screening tool for colon polyps and cancer. Screening is testing for diseases when a person does not have any symptoms or if a person is of 50 years of age or older and there is an average risk of developing colon cancer. The doctor may recommend a colonoscopy every ten years or sometimes sooner to screen for colon cancer.
  • To check if there are more polyps. If a person has a family history of benign polyps or a familial adenomatous polyposis (FAP) or Lynch syndrome, the doctor may recommend a follow-up colonoscopy to look for and remove any additional polyps. This is done to reduce the risk of colon cancer and diagnose invasive cancer.

Risks Associated with Colonoscopy

Only 5 out of 1,000 people will have a serious complication during colonoscopy. Complications can be treated with antibiotics, blood transfusion, hospitalization, repeat colonoscopy or surgery.

There are low chances of dying from colonoscopy. However, a colonoscopy involves the following complications:

  • Allergic reaction to the sedative used during colonoscopy
  • Bleeding when a biopsy is done where a tissue sample was taken or a polyp or other abnormal tissue was removed
  • A tear in the colon or rectum wall 

Risk Factors for Colorectal Cancer:

  • If you are a male
  • If you are an African American
  • If there is a personal history of inflammatory bowel diseases, such as ulcerative colitis and Crohn’s disease
  • Presence of Lynch syndrome that increases the risk of colorectal cancer
  • Family history of colon cancer
  • Previous treatment with radiation therapy
  • If a person weighs too much or smoke cigarettes 
  • If one has already attained the age of 75 years 

What Should You Do Before Colonoscopy?

Before a colonoscopy, it is important to inform the doctor if you are dependent on some medications, health problems and facing any complications.

  • If you are taking medicines for arthritis, aspirin or medicines that contain aspirin, blood thinners, diabetes and other anti-inflammatory drugs such as ibuprofen or naproxen 
  • Heart condition
  • Lung condition
  • Pregnancy 
  • Any kind of allergy towards medicine
  • In a case that you have diabetes or meds that can influence blood clumps. These medications may require alterations before colonoscopy. 

Preparing for Colonoscopy 

After consulting a doctor, the patient may be asked to stop taking some medications up to one week before the procedure.

On the day of the procedure:

  • Wear comfortable clothing.
  • Make plans for a ride home after the procedure to ensure safety while traveling
  • The patient will be asked to empty the Colon completely before the procedure. Presence of stool in colon can block the view. This preparation usually starts several days before the procedure. The healthcare professional will give the patient a written bowel preparation instruction to follow at home. Usually, patients need to follow a clear liquid diet two to three days before the procedure.

It is important to have a clean colon to increase the success of the procedure. Cleansing methods may include any of the following methods:

  • Enemas are a process when fluid is introduced into the rectum to stimulate a bowel movement
  • Laxatives medications that cause a patient to have soft bowel movements
  • Oral cathartic medications is a fluid given to patients to drink, it helps stimulate the bowel movement.

Procedure of Colonoscopy

When the procedure starts, the patient is asked to lie on the left side with knees drawn up toward the chest. Then the doctor inserts the colonoscope slowly through the rectum and air is blown into the colon. This inflates the colon so the doctor can have a clear view of the lining in the colon and rectum. The colonoscope is gently passed through the colon to view the entire area and one may need to change position slightly to allow better access. If there is any kind of abnormal growth or a polyp is detected in colon, the doctor uses a tool at the end of the colonoscope to remove the polyp or perform a biopsy. This procedure is usually painless, but sometimes bleeding may occur at the site where the tissue is removed. The doctor can stop the bleeding by using the colonoscope. It takes 30 to 60 minutes to complete the entire process.

After a Colonoscopy

After the procedure is complete, patient needs to stay at the center for at least two hours for the effects of the sedative to wear off. A friend or family member can drive them home. After the colon examination, doctors may work out on how far it has spread. Tissue taken at the time of colonoscopy may be used for testing genetic changes in the cancer cells. This, in turn, can influence the choice of treatment. 
After a colonoscopy, most people do not have bowel cancer. However, it is important to monitor recovery. Call the doctor if any of the following symptoms occur:

  • Heavy bleeding from rectum
  • Black, sticky or tarry stools
  • Severe abdominal pain
  • Hard and swollen abdomen
  • Signs of infection
  • Bloating
  • Fever or chills
  • Difficulty to pass gas or stool
  • Coughing, shortness of breath, chest pain, severe nausea or vomiting

It can be concluded that colonoscopy is a primary test that is used to analyze and diagnose the cancer of bowel. Different tests used to analyze gut malignancy incorporate virtual colonoscopy and sigmoidoscopy. Also, it is an established fact that colonoscopy is a useful process and less time consuming.
Follow Elacancer Blogs for latest updates on cancer treatments and technologies related to it. Call at +91-8929020600 for more information about cancer therapy, services, and treatment. 

Dr. Prasenjit Chatterjee

About the Author

Medical Oncologist
Dr. Prasenjit Chatterjee is a Radiation and Medical Oncologist practicing in AMRI Hospital and Apollo Clinic in Salt Lake, Kolkata. He has completed his MBBS from Burdwan Medical College in this year 1990. Further, he pursued Diploma in Radiotherapy from Tata Memorial Hospital, Mumbai in the year 1996 and DNB in Radiation Oncology from Tata Memorial Hospital, Mumbai in 1997. Dr. Prasenjit has received "Best Paper Award" in the 1st SAARC Conference on Clinical Oncology which was held in Dhaka, Bangladesh in the year 2001. Further, he was awarded Bharat Jyoti Award on Behalf of IIFS and was selected For Best Citizen India, Published by International Publishing House in the year 2010. Dr. Prasenjit Chatterjee has also received Rashtra Pratibha Puraskar in the year 2012. He is a member of various medical associations such as Indian Medical Association (IMA), Indian Cooperative Oncology Network, and Association of Radiation Oncologists of India (AROI). Later, he joined the Pediatric Radiation Oncology Society (PROS), Cancer Patients Aid Association (CPAA), and International Lung Cancer Society (ILCS). Dr. Chatterjee is also a member of American Society of Radiation Oncology (ASTRO), as well as European Society of Medical Oncology (ESMO). Dr. Prasenjit Chatterjee specializes in Gynecology cancer treatment, Hysterectomy, Lymph node dissection, Mastectomy, Mammaplasty, and Tissue expansion procedures. He also specializes in Wedge resection, Salpingo-oophorectomy, Retroperitoneal lymph node treatment, and Laparotomy surgery. Dr. Prasenjit Chatterjee has experience of more than two and a half decades in the field of oncology. Dr. Chatterjee practices at Apollo Gleneagles Hospital and Woodlands Multispeciality Hospital Limited. Dr. Prasenjit Chatterjee is also associated with Apollo Clinic branch located in Behala, Kolkata. Book a FREE appointment with Dr. Prasenjit Chatterjee at
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    1 Comment

    Suprakash Karumuri
    Nov. 19, 2018, 5:02 p.m.
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