Colorectal cancer is the fourth most common cancer in Korea. According to the ‘2019 National Cancer Registration Statistics’ announced by the Ministry of Health and Welfare and the National Cancer Center, colorectal cancer accounted for 29,030 cases (11.4%) out of 254,718 cancer cases, ranking fourth after thyroid cancer, lung cancer, and stomach cancer. did.
As colorectal cancer has increased significantly due to a westernized diet and an increase in the obese population, the mortality rate has also increased. As of 2019, the colorectal cancer mortality rate was 17.5 per 100,000 people. Compared to 2009 (14.3 per 100,000), it increased by 22.1% in 10 years, ranking third in cancer mortality.
◇In 30-40% of people over 50 years old, polyps in the colon
One of the main causes of colorectal cancer is colorectal polyps. A lesion that protrudes from the surface of the colonic mucosa toward the lumen. It is so common that it is detected during colonoscopy in 30-40% of people over 50 years of age.
According to histological findings, it is divided into adenomas and hyperplastic polyps. Among them, adenoma is a representative neoplastic polyp that can aggravate into colorectal cancer.
70% of colorectal cancer begins with an adenoma. It usually takes 5 to 10 years for an adenoma to turn into a cancer, so early detection and removal can prevent most cancers.
Although it is rarer than adenoma, polyps such as sawtooth squamous lesion (neckless sawtooth lesion) or traditional sawtooth adenoma are also pointed out as neoplastic polyps that must be removed.
◇For early detection of polyps, colonoscopy should be performed from the age of 45.
Visually, it is difficult to distinguish whether a colorectal polyp is neoplastic or non-neoplastic. Therefore, if a polyp is found during a medical examination, it is a principle to remove it except for some that are non-neoplastic.
Since neoplastic polyps are a pre-stage colorectal cancer, risk factors are similar to those of colorectal cancer. There are genetic and biological factors such as family history, gender, and age, and there are environmental factors such as obesity, smoking and drinking, as well as increased intake of fatty foods, red meat, and processed meat.
Some polyps cause bleeding, mucous discharge, or changes in bowel habits. However, most are asymptomatic and are discovered incidentally during colonoscopy. Even if there are no specific symptoms, it is important to have regular colonoscopy from the age of 45.
◇Removal of colorectal polyps is the surest way to prevent colorectal cancer
Colorectal polyps can be removed during endoscopy using tissue biopsy forceps or by polypectomy or mucosal resection using an electric snare. In some types, such as very large or flat polyps, ‘endoscopic submucosal dissection’ is attempted. It is a method of exfoliating under the mucous membrane using an electric knife that looks like a needle that goes into the endoscope.
If you have a history of removing polyps, it is important to follow-up examinations according to the recommendations of the gastroenterologist who performed the colonoscopy. The frequency of follow-up examinations varies depending on the size and number of polyps, and the results of biopsy.
Colonoscopy, which had previously been recommended from the age of 50, has recently increased to 45 years of age at the beginning of the examination. If a member of your immediate family has had colorectal cancer, it is recommended that you start colonoscopy from the age of 40.
It is recommended that colonoscopy be performed until the age of 75. Between 76 and 85 years of age, it can be decided in consultation with a specialist based on individual choices and individual health conditions.
Park Ye-hyeon, a professor of gastroenterology at Ewha Womans University Seoul Hospital, said, “It is unfortunate that many people think that the preparation and procedure for colonoscopy is cumbersome and difficult.”
Kwon Dae-ik Medical Specialist reporter>
