Weight Loss, Bariatric & Metabolic Surgery

Upper Gastrointestinal, Oesophageal & Stomach Surgery

Cancer Screening, Endoscopy / Gastroscopy & Colonoscopy

Keyhole and General Surgery

Emergency and Acute Care Surgery



What is a colonoscopy?

In colonoscopy, a long thin flexible tube with a small light and camera at the end is inserted through the anus and rectum until the caecum (beginning of the colon). It is connected to a screen that allows Dr Tan to evaluate any abnormalities seen along the way.

You will be given sedation just before the start of your colonoscopy.

During the examination, any polyp that is found will be removed immediately to prevent colorectal cancer from potentially developing.


Who should go for colonoscopy?

If you have the symptoms mentioned below, you should have a colonoscopy.
If you have any of these symptoms

Medical History

Lifestyle and Dietary Risk Factors

Early detection saves lives.
Schedule your colonoscopy today.

Some of the above-mentioned signs may be suggestive of colorectal cancer

Colorectal cancer is the most common cancer in Singapore. It is also the most common cause of death in Singapore. Survival depends on the stage of disease upon detection. 5-year survival in early stages is up to 95%, while in advanced disease is <5%.

Most colorectal cancers start out as polyp. The time for progression from a pre-malignant polyp to invasive cancer may be 5 years or more. A window of opportunity exists when these polyps may be safely removed via colonoscopy, effectively preventing the development of colorectal cancer.

Before the Procedure

During the Procedure

After the Procedure

20+ Years of Clinical Expertise

Dr Tan Chun Hai (陈俊海医生)

Upper Gastrointestinal, Bariatric & General Surgeon

Endoscopy & Minimally-Invasive Surgery Specialist

Dr. Tan Chun Hai is a dual fellowship-trained specialist in laparoscopic (keyhole) stomach cancer surgery and Bariatric & Metabolic surgery. His clinical expertise includes the use of minimally invasive surgical techniques for stomach-related disorders, gallstones, appendicitis and Gastroesophageal Reflux Disease.

Dr. Tan also specialises in performing endoscopies/gastroscopies and colonoscopies. When applicable, Dr. Tan provides same-day treatment within a few hours of diagnosis. Dr. Tan subscribes to a less invasive practice, promoting less postoperative pain and shorter hospital stays.

Have a concern?

Give us a call at 6250 5610 or WhatsApp us at 8870 3848.


Frequently Asked Questions

  • Generally, a colonoscopy takes less than 30 minutes. If there are polyps to be removed or abnormalities detected, it may take longer.
  • Any polyps seen will be removed immediately and sent to the laboratories.

  • Colorectal polyps are abnormal growth of cells on the inner lining of the colon and rectum. They are common and incidence increases with age.
  • Most polyps are benign (not cancer). But because polyps are caused by abnormal cell growth and, like cancer, grow through rapidly dividing cells, they can become cancerous.
  • Through a colonoscopy, the polyp can be removed and sent for examination by a pathologist. Colonoscopy and removal of polyps decreases the incidence of colorectal cancer. Countries with colorectal cancer screening programs have reported a significant drop in colorectal cancer cases and deaths. This is due to early detection of colorectal polyps with colonoscopy, the removal of which prevents the development of cancer.
  • The treatment of colonic polyps involves performing a colonoscopy and removing the entire polyp. The removed polyp is then sent for histological examination to determine if it is benign (not cancer) or a malignant change (cancerous) has already occurred.
  • Depending on the number and size of polyps removed, a follow up colonoscopy will be recommended from 1 to 5 years later. If there are any cancer cells found in the polyp, surgery may be required.
Yes, we can schedule for gastroscopy and colonoscopy at the same visit.
A colonoscopy is usually performed as an outpatient procedure, which means you will not have to spend the night in the hospital. With sedation, you will be placed under close monitoring at the endoscopy centre. You will be discharged when it’s safe to do so.

Colonoscopy remains the gold standard of detecting and removal of colonic polyps. Other options can be considered for patients who are not fit for colonoscopy, or would like a non-invasive option.

CT Colonography – this is a virtual colonoscopy performed by a CT scanner. It is being used to screen for polyps in the large intestine. After adequate bowel preparation, a tube is inserted into the rectum to inflate with gas while CT images of the colon and rectum are taken from various angles.

Barium Enema – this entity is seldom used nowadays with the advent of CT colonoscopy. It involves using a white solution being inserted into the anus via a tube to coat the lining of the colon. This allows the colonic lining to be visible on X-ray, highlighting any difficulties of the white solution going through indicating an abnormality at the region.

While these options are able to detect polyps in the colon, they are not as accurate as colonoscopy. In the event these polyps are found, colonoscopy will still have to be performed to remove them. Colonoscopy is still the recommended method for screening for colorectal cancer. Dr Tan will advice you according to your needs and preferences.

  • Reaction to the sedation.
  • Perforation of the colon is rare, occurring in less than 0.1% of colonoscopy.
  • Bleeding after polypectomies. Please inform Dr Tan if you are on blood thinners or anti-platelets medications. These are usually started if you had a stroke, heart attack or stent placed in your body. These medications are usually started by your GP, cardiologist or neurologist. Bleeding can occur immediately after the scope, or up to 10 days after the procedure.
  • Abdominal Bloating – this usually settles within a day or two after the endoscopy.
  • Sore throat