These five groups of people are at high risk of colorectal cancer. How can they be detected early?

Author: Jiang Bo, Chief Physician of Beijing Tsinghua Chang Gung Hospital affiliated to Tsinghua University

Reviewer: Yao Shukun, Chief Physician, China-Japan Friendship Hospital

Many people cannot distinguish between colorectal cancer, rectal cancer and colon cancer.

The lowest end of the intestine is the rectum. The sigmoid colon, descending colon, transverse colon, ascending colon, and cecum above the rectum are collectively called the colon. The rectum and colon are collectively called the large intestine, so colorectal cancer includes two parts: rectal cancer and colon cancer.

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1. Who are the high-risk groups for colorectal cancer?

As people age, the incidence of colorectal cancer gradually increases, so the first factor is age. People over 50 years old are a high-risk group and should be checked regularly.

The second is a family history of colorectal cancer. If first-degree relatives including parents, siblings, or others have had colorectal cancer, then your own risk of developing colorectal cancer increases by more than five times.

Third, if you have inflammatory bowel disease for more than 8 years, including ulcerative colitis and Crohn's disease, the incidence of colorectal cancer will increase significantly, and the risk will be more than 10 times; if you have inflammatory bowel disease for 20 years, the risk can be more than 30 times, so this group of people should undergo regular check-ups.

Fourth, if there is a family history of polyposis or non-hereditary polyposis, close follow-up is required.

Fifth, patients who have had appendicitis or cholecystectomy also need to pay attention to colorectal cancer.

For the general population, if there is no obvious family history, no genetic susceptibility, no ulcerative colitis, no intestinal polyps, and no precancerous lesions, you should be checked at the age of 50. If there is nothing abnormal, you can do a second check ten years later. In other words, if there is no problem at the age of 50, you can check again at the age of 60. If there is no problem at the age of 60, you can check it for the last time at the age of 70, and you don’t need to check it again.

If you have the above high-risk factors, you should have regular screening starting at age 40. For example, if you have a family history of colorectal cancer, you may need screening every 3-5 years. If you have inflammatory bowel disease, you may need screening every one or two years and should follow up strictly. If you have intestinal polyps or adenomatous colon polyps, you should arrange the screening frequency based on the specific situation of the polyps and the doctor's advice.

2. How to detect colorectal cancer early?

If you experience abdominal discomfort, changes in bowel habits, blood in the stool, or positive fecal occult blood, you should get checked to rule out colorectal cancer.

Early colorectal cancer can be detected, but it is important to remember that when symptoms appear, it is basically in the late stage of progression. If you go for examination and screening when there are no symptoms, 70%-80% of the cancers you find are early stage cancers.

The most intuitive way to screen for colorectal cancer at an early stage is colonoscopy. There are also some non-invasive tests, such as fecal occult blood test or immunochemical test, which are good screening methods. If the fecal occult blood test is positive continuously, the doctor will definitely tell you to do a colonoscopy.

Blood on the surface of the stool usually indicates a lesion in the sigmoid colon; blood mixed in the stool is often blood from the proximal colon; blood dripping after defecation is often more likely to be hemorrhoids. If there is blood on the surface of the stool or blood mixed in the stool, a colonoscopy must be performed.

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3. How to treat early colorectal cancer?

There are many treatments for early colorectal cancer. It does not mean that surgery is required once cancer is discovered. Endoscopic technology is developing very rapidly and is very popular in our country.

For example, endoscopic mucosal dissection (EMR technology), piecemeal mucosal resection (EPMR technology), and endoscopic mucosal resection (ESD technology), etc. The treatment effect is very good in many cases, and the tumor problem can be completely solved under endoscopy.

Can early colorectal cancer and precancerous lesions be treated through endoscopic technology?

Early colorectal cancer that invades less than 2/3 of the mucosa can be treated endoscopically. If it invades the entire submucosal layer, it is no longer within the scope of endoscopic treatment and the entire section of the intestine must be removed. This needs to be done under laparoscopy or open surgery.