colonpolyps

What is the grim reality of colorectal cancer?

       Colorectal cancer is the third most commonly diagnosed cancer in males and the second in females, with 1.8 million new cases and almost 861,000 deaths, according to a 2018 WHO report. It is estimated that in 2020 in USA, approximately 147,950 individuals will be diagnosed with colorectal cancer and 53,200 will die from the disease, including 17,930 cases and 3,640 deaths in individuals aged younger than 50 years.

Why colorectal cancer is preventable? And how?

          A polyp is a growth on the lining of your gut, a term used indiscriminately by endoscopist and the public. There are two main categories of polyps, non-neoplastic and neoplastic.Hyperplastic polyps, inflammatory polyps and hamartomatous polyps are nonneoplastic, and having almost no potential for being malignant. Adenomas and serrated types are neoplastic. In general, the larger a polyp, the greater the risk of cancer, especially with neoplastic polyps.

          The forming of colorectal cancer has a conventional adenoma-carcinoma pattern or serrated pathway.From the time a polyp is first detectable during colonoscopy until it turns into cancer takes 10-12 years!

          Colonoscopy is the single one step test to find polyps and to mini-invasively remove them, thereby preventing cancer.

What is a colonoscopy procedure like?

          A colonoscopy is done by an endoscopis steering a colonoscope  to view the linings of  the rectum, the colon,and often a small part of the terminal ileum.It takes about 30 to 60 minutes to complete. A colonoscope is a 130cm to 160cm long, index-finger thick,smooth and flexible tube with a tiny video camera and light source at the tip.  Channels are ingeniously built in for special instruments passing to and fro to clear the bowel,to obtain a biopsy, or to remove polyps.

          During the procedure, you'll wear a gown. Sedation is usually recommended. Sometimes a mild sedative is given.

          You'll begin the exam lying on your side on the exam table, usually with your knees drawn toward your chest. The endoscopist will gently insert a colonoscope into your anus and advance through the rectum and colon. If you are awake, you may feel abdominal cramping or the urge to have a bowel movement when the scope moves or when air is pumped inside.

What are the symptoms prompting me to do a colonoscopy?     

        If you have the following symptoms lasting over a week or persistent ,you may need a colonoscopy.

        Rectal bleeding or blood or mucus/pus in your stool

       A change in your bowel habits, including diarrhea or constipation or a change in the form of your stool or a feeling that your bowel doesn't empty completely

       Persistent abdominal pain,cramps or gas

        losing weight or feeling weakness or fatigue for no reason

       Iron deficiency anemia

      Occult blood in stools

I am feeling fine, should I do colonoscopy? And when?

       Colon cancer usually begins as small, unsymptomatic  polyps, so we recommend regular screening colonoscopy to help prevent colon cancer by identifying and removing polyps before they turn into cancer.

       If you are  aged 50 years and older,colonoscopy is strongly recommended.

       If you are aged 40 years and have a family history of adenomas or colorectal cancer in a first degree relative,colonoscopy is recommended.

      If you are  aged 45 years and older, you can choose either a stool  test or colonoscopy.

Who are at increased or high risk for developing colorectal cancer？

        personal history of adenomas  or a personal history of colorectal cancer,

        a family history of colorectal cancer or advanced adenomas diagnosed in a first degree relative before age 60,

        a personal history of inflammatory bowel disease of significant duration,

        a confirmed or suspected hereditary colorectal cancer syndrome,

        a history of abdominal or pelvic radiation for a previous cancer

        Cystic fibrosis,obesity and diabetes

Why is it so important and time consuming to prepare the bowel?

        Good bowel preparation is crucial to a successful colonoscopy exam. If you go to the dentist and forgot to brush your teeth, you must feel very embarrassed; the same is true for colonoscopy. Poor colonoscopy preparation can prevent your doctor from finding polyps, tumors and other lesions. It also increases the examination time and the risk of complications. In many cases, the exam has to be rescheduled or redone.

What should I eat before the colonoscopy?

         Follow a special diet the day before the exam. Typically, you won't be able to eat solid food the day before the exam. Drinks may be limited to clear liquids -plain water, tea and coffee without milk or cream, broth, and carbonated beverages. Avoid red liquids, which can be confused with blood during the colonoscopy. You may not be able to eat or drink anything after midnight the night before the exam.

How should I adjust my medications before and after the procedure?

        Remind your doctor of your medications at least a week before the exam.

        If you take blood thinners,such as aspirin,warfarin,dabigatran,rivaroxaban or clopidogrel, discuss it with the endoscopist and your prescribing provider.

        If you take any oral medicine or insulin for diabetes, contact your primary care doctor or diabetes doctor about any changes needed in your medicine dose.

       If you take vitamins, iron pills, or liquid antacids, stop taking them 5 days before your procedure.

What should I do if I have severe constipation or gastroesophageal reflux disease?

        If you have a history of severe constipation,gastroesophageal reflux disease, or any other problems with digestion, contact your gastroenterology doctor at least 2 weeks before your procedure to discuss the right laxative and diet plan for you.

What is the most unpleasant part of the colonoscopy? Can you give me some tips?

        Many patients find the bowel preparation to be the most unpleasant part of the test. The medication you take to clean out your colon will most likely cause you to be in the bathroom quite a bit. The most common colonoscopy preparation calls for drinking 1 gallon (3.8 liters) of a polyethylene glycol solution(PEG). Many people don't complete the full preparation.

        It is common to feel nauseous or sick to your stomach during your bowel preparation. Here are some tips you can try to help you drink the laxative:

       Rest for 30 minutes then continue to drink the laxative every 20-30 minutes as tolerated.

       Use a straw to drink the laxative.

      Chill the laxative in the fridge and drink it cold.

      Add some fruit juice, Crystal Light, or ice to the laxative to help make it taste better. Don’t use any red, purple or orange colored fruit juice or Crystal Light.

       Chew gum or suck on lemon or hard candy in between drinks to help with the taste.

I hate to take so much distasteful fluids, doctor, can you offer me a better one?

       Actually there are a variety of preparation methods for colonoscopy besides the one with PEG. Smaller volumes of solution  or pill preparations have also recently become available with similarly good outcomes to PEG for people who dread the thought of large volumes of liquid.

       Another preparation involves a phosphate solution (called Fleet® Phospho-soda) which consists of two  rounds of phosphate rich liquid of 45 ml each the night before and day of the exam. It is essential to drink at least 2 quarts of water with these preps to replace losses.

Why do I need to arrive early to the endoscopy unit?

        It is important to arrive at the time listed in your bowel preparation packet to allow us to get you ready for your procedure. This includes filling out paperwork, changing into a hospital gown, taking your vital signs, placing an IV (intravenous) catheter in your arm for medicine, and answering any questions you have about the procedure. Please arrive on time to prevent delays in starting your procedure.

What do I expect after a procedure?

         Following your procedure you will be wheeled into the recovery room where you will rest to allow the sedation to wear off. It is important after a colonoscopy to pass the wind that may be trapped in the bowel.It is important to rehydrate following the procedure-drink plenty of fluids. You may return to a normal diet immediately following discharge, unless directed otherwise.Most people are able to resume normal activities the following day.

         If your doctor removed a polyp during your colonoscopy, you may be advised to eat a special diet temporarily.You may also notice a small amount of blood with your first bowel movement after the exam. Usually this isn't cause for alarm. Consult your doctor if you continue to pass blood or blood clots or if you have persistent abdominal pain or a fever.

What might my doctor recommend if my colonoscopy find nothing abnormal?

        If no polyps requiring surveillance are detected at first surveillance colonoscopy, a second surveillance  colonoscopy after 5 years is recommended.After that, if no polyps requiring surveillance are detected, you can start screening colonoscopy at 10 years.

       If you have a history of polyps in previous colonoscopy procedures,and no polyps found at this session, a second colonoscopy after 5 years is recommended.

       If there was residual stool in the colon preventing thorough examination of your colon, repeat colonoscopy at one year is recommended.  

What might my doctor recommend if my colonoscopy find polyps needing surveillance?

       If your doctor finds one or two polyps less than 0.4 inch (10 mm) in diameter, a repeat colonoscopy in five to 10 years is recommended, depending on your other risk factors for colon cancer.

      If you have a  complete removal of at least 1 adenoma larger than 10mm or with high grade dysplasia, or more than 5 adenomas, or any serrated polyp larger than 10mm or with dysplasia, repeat colonoscopy at 3 years is recommended.

      If you have a piecemeal endoscopic resection of polyp larger than 20mm, repeat colonoscopy at 3 or 6 months is recommended. And after that, repeat colonoscopy at 12 months is recommended.

Why my doctor ask me to remove my polyp at next session instead of this one?

      If you have a polyp or other abnormal tissue that couldn't be removed during the colonoscopy, your doctor may recommend a repeat exam with a gastroenterologist who has special expertise in removing large polyps, or surgery.

What are the common complications that arise from colonoscopy ?

       Intolerance to the bowel preparation. Some people develop dizziness, headaches or vomiting.

      Reaction to the sedative. This is very uncommon but is especially of concern in people who have severe heart disease or lung disease.              Many patients feel sleepy and tired after the procedure.

      After colonoscopy, bloating and cramps is common.

      The more serious complications include bleeding or perforation. Bleeding may occur after a polyp is removed.  A perforation of your bowel will cause severe abdominal pain and fever.Serious complications  are rare, at less than one in 3,000 examinations.   

Why many people haven’t done colonoscopy?

      The most common reason for people not getting a colonoscopy is that their doctor did not discuss it with them. The next most common reason is fear or avoidance of the preparation . In addition, many people are simply unaware that they need colon cancer screening.

How do I predict that I might have colorectal cancer?

        Your lifetime risk of getting colorectal cancer is approximately 6% . Your risk is roughly doubled if one  first degree relative (parent, sibling or child) had colon cancer or polyps after age 50, and is higher if the cancer or polyps were diagnosed at a younger age or if more members of your family are affected. Certain inherited disorders, for example, polyposis syndromes and hereditary non-polyposis colorectal cancer, can increase your risk of developing colon cancer. Other important risk factors include obesity, cigarette smoking, inflammatory bowel disease, and excessive alcohol consumption.

What are the high risk inherited disorders for colorectal cancer?

       Lynch syndrome, also called hereditary nonpolyposis colorectal cancer. People with Lynch syndrome tend to develop relatively few colon polyps, but those polyps can quickly become malignant.

       Familial adenomatous polyposis (FAP), a rare disorder that causes hundreds or even thousands of polyps to develop in the lining of your colon beginning during your teenage years. If the polyps aren't treated, your risk of developing colon cancer is nearly 100 percent, usually before age 40.

       Gardner's syndrome, a variant of FAP that causes polyps to develop throughout your colon and small intestine. You may also develop noncancerous tumors in other parts of your body, including your skin, bones and abdomen.

        Peutz-Jeghers syndrome, a condition that usually begins with freckles developing all over the body, including the lips, gums and feet. Then noncancerous polyps develop throughout the intestines. These polyps may become malignant, so people with this condition have an increased risk of colon cancer.

         Serrated polyposis syndrome, a condition that leads to multiple serrated adenomatous polyps in the upper part of the colon. These polyps may become malignant.

Take home message

         A high performance colonoscopy is the only one step test to keep colorectal cancer at bay. If you notice any persistent symptoms that worry you during the surveillance interval, make an appointment with your doctor. Repeat a colonoscopy sooner than planned if warning symptoms occur.

References

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10.https://gi.org/topics/colonoscopy/