Many people believe that if they have no stomach pain and their bowel movements are normal, their intestines must be healthy, and there is no need for a colonoscopy.
However, in clinical gastroenterology, there lies a truth that subverts popular perception: 80%-95% of colorectal cancers gradually evolve from intestinal polyps, with the entire process lasting 5-10 years. This process is highly insidious, with almost no symptoms in the early stages, making it extremely easy to be overlooked by people.
① The carcinogenesis of polyps involves only four steps, and the entire process is irreversible
Intestinal polyps are protruding growths on the intestinal mucosa. Many people do not take them seriously after being diagnosed, thinking that they are benign minor issues that do not require treatment.
Intestinal polyps are protruding growths on the intestinal mucosa. Many people do not take them seriously after being diagnosed, thinking that they are benign minor issues that do not require treatment.
Professor Zhao Xinkai from the Department of Gastroenterology explained that the risk varies greatly depending on the type of polyps. Adenomatous polyps are clear precancerous lesions that cannot regress spontaneously and can undergo continuous malignant transformation. They generally progress into colorectal cancer in four steps:
Step 1: Normal mucosa → Microproliferative polyp
Prolonged sitting, high-fat diet, staying up late, intestinal inflammation, and age all stimulate the intestinal mucosa to grow several millimeters of tiny polyps. At this stage, the polyps are benign and asymptomatic, and cannot be detected by ordinary examinations. Only colonoscopy can identify them, and timely removal can completely prevent canceration.
Step 2: Micro-polyp → Large adenomatous polyp
If left unchecked, polyps will grow larger year by year, reaching over 1 cm and transforming into adenomatous polyps, officially entering the high-risk stage; if the polyps exceed 1.5 cm, the risk of canceration increases significantly.
Step 3: Adenomatous polyp → Atypical hyperplasia
The continuous growth of polyps leads to cell mutations and disordered arrangement, resulting in atypical hyperplasia. High-grade atypical hyperplasia is close to carcinoma in situ, which is a critical point of carcinogenesis. Although the cells have undergone malignant changes, there is still no obvious discomfort, making it extremely easy to miss the diagnosis.
Step 4: Atypical hyperplasia → Invasive colorectal cancer
Abnormal cells penetrate the intestinal mucosa and invade deep tissues, developing into invasive intestinal cancer. Patients may experience symptoms such as bloody stool, black stool, abnormal bowel movements, abdominal pain, and unexplained weight loss. By the time they notice significant discomfort, it is often in the middle or late stages, making treatment challenging and prognosis poor.
② After turning 40, it is essential to undergo a colonoscopy
Many people think, "I'm not feeling unwell, so there's no need." However, the National Health Commission has explicitly recommended that people should undergo their first colonoscopy after the age of 40, and ideally no later than 50.
Why should one undergo colonoscopy even without symptoms? Because colonoscopy not only enables early detection of colorectal cancer, but also identifies asymptomatic colorectal polyps and precancerous lesions, allowing for timely treatment before the issues escalate into "major troubles".
High-risk groups should undergo screening early, especially those who are over 50 years old, male, have a long history of smoking and drinking, are overweight, exercise infrequently, have a history of intestinal polyps, or have a family history of colorectal cancer.
Special reminder: If there are colorectal cancer patients among your parents, children, or siblings, and they were diagnosed at a younger age, your screening time should be advanced by 10 years.
After undergoing a colonoscopy, how often should you get it done again? If no issues are found: wait 5 years before getting another one, and then maintain a schedule of every 5 years thereafter. If polyps or precancerous lesions are found: the next examination should be within 1 year.
Note: If you have experienced long-term abdominal discomfort, black stool or blood in stool, changes in bowel habits, narrowed stool, or unexplained weight loss, regardless of age, it is important to visit the hospital as soon as possible, not just for screening.
③ Keep away from intestinal polyps by following these 5 tips
Eat more fresh fruits and vegetables: dietary fiber cleanses the intestines, maintains the balance of gut microbiota, and vitamins enhance immunity.
Reduce high-fat foods: Eat less fried food, fast food, and pastries, and choose fish, chicken breast, and beans.
Control processed meat and red meat: Eat less bacon, sausage, etc., and eat white meat and soy products in moderation.
Ensure adequate water intake: 1500-1700 milliliters per day to help eliminate intestinal waste.
Maintain moderate exercise: engage in at least 150 minutes of moderate-intensity aerobic exercise (such as brisk walking, swimming, etc.) per week.
Expert Introduction
Zhao Xinkai, Chief Physician
Vice President, Doctor of Medicine
Professor, Master's Supervisor
Gastrointestinal Oncology Endoscopy and Diagnosis Department, Gastroenterology Department
The director of the Endoscopy Integrated Diagnosis and Treatment Center also serves as an expert in the International Department
High-level talents in Hainan Province
Winner of the May 1st Labor Medal in Hainan Province
Medical expertise
He is skilled in various complex and difficult techniques of digestive endoscopy, such as ERCP and related techniques, ESD and related techniques, ultrasonic endoscopy techniques, PEG techniques, capsule endoscopy techniques, small intestinal endoscopy techniques, and other endoscopic diagnosis and treatment techniques.