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Colon cancer is the fourth leading cause of death in the world and the fifth in Vietnam. If detected and treated at an early stage, the cure rate is up to 90%. So how to detect early, treat effectively as well as prevent this dangerous disease?

According to Globocan’s statistics in 2020, Vietnam recorded nearly 16,000 new colon cancer cases, more than 8,200 deaths from this disease. The disease is common in people over 50 years old, but in recent years, the incidence has increased rapidly in young people.

Currently, this is the fifth most common cancer in Vietnam, after liver cancer, lung cancer, breast cancer and stomach cancer.

What is colon cancer?

Colon Cancer is cancer that occurs in the colon (the longest part of the large intestine). This is a common cancer diagnosed in both men and women.

The colon wall is composed of many layers. Cancer cells are formed from the cells lining the inside of the colon (mucosa), largely due to the growth of polyps in the colon. After appearing on the wall of the colon, cancer cells begin to move into blood vessels or lymphatic vessels (small tubes responsible for carrying waste and fluid out).

That means cancer cells can spread to nearby lymph nodes, or they can travel further to other organs in the body.

Most colon polyps are benign, but they also carry a risk of becoming malignant. There are two main types of polyps:

  • Adenomatous polyps (adenomas): This type of polyp sometimes develops into cancer, so it is also called a precancerous condition.
  • Hyperplastic and inflammatory polyps: These are the more common types of polyps, not precancerous conditions.
  • Dysplasia is also a precancerous condition that occurs in the polyp itself or the lining of the colon when abnormal cells are present.

Is colon cancer dangerous?

This is a question that many patients care about. Dr. Tran Vuong Thao Nghi, Head of Oncology Department, Tam Anh General Hospital in Ho Chi Minh City, said that colon cancer is one of the cancers with a good prognosis, meaning the degree of danger of the disease. If the patient is treated promptly and actively, the chances of survival are high, many cases of early detection and treatment at the early stage can cure the disease.

However, if not detected early and treated in time, cancer in the colon can metastasize to other organs and organs in the body, causing dangerous complications such as: bowel obstruction, intestinal perforation, compression leading to pain. The prognosis of the patient in this case is greatly reduced, the treatment is difficult, the survival time after 5 years is shortened, “said Dr. Tran Vuong Thao Nghi.

Signs of colon cancer

Colon cancer often has no symptoms in its early stages, but warning signs are often:

  • Blood in the stool, or mucus in the stool;
  • Changes in the nature and shape of stools (such as stools that are flatter than usual, have an unusual fishy smell, etc.);
  • Change in bowel habits (wild bowel movements, constipation or diarrhea, etc.);
  • Diarrhea, constipation, or a feeling that the bowels are not clean;
  • Body weakness, fatigue;
  • Unexplained weight loss;
  • Abdominal pain or discomfort in the lower abdomen;
  • Vomiting;
  • The appearance of a tumor in the abdomen, the abdomen gradually enlarges…​

Causes of colon cancer

  • Genetic factors: Colon malignancies occur when there is a change in certain genes, which is associated with some inherited syndromes such as familial polyposis (FAP), familial colonic polyposis (FAP) and colon cancer. hereditary nonpolyposis colon cancer (HNPCC or Lynch syndrome).
  • Precancerous lesions: Bleeding colitis, Crohn’s disease, Colon polyps…
  • Nutritional factors: Diet high in meat, animal fat, low in fiber, vitamin deficiency, or foods containing nitrosamines…

Although the mechanism and cause of gene mutations are still unknown at present, there are a number of risk factors that can increase the likelihood of colon cancer, including:

Overweight or obese

Being overweight or obese can increase your risk of disease, as well as a higher risk of dying from cancer. This condition occurs in both sexes, but the risk is higher in men than in women.

A sedentary lifestyle

Unscientific lifestyle, less physical activity increases the risk of colon cancer. Therefore, it is necessary to develop a reasonable and moderate exercise plan to eliminate the risk of disease.

Unscientific diet

Diet too much red meat (beef, pork, lamb, liver …), processed foods (sausages, canned meat…) can increase the risk of cancer. In addition, the processing of food at too high a temperature (frying, baking …) will create harmful chemicals, increasing the risk of cancer. Therefore, it is recommended that you build a scientific diet, add lots of vegetables, fruits, whole grains, limit red meat, and canned processed foods to reduce the risk of cancer. letters.


People who smoke cigarettes regularly for a long time have a higher risk of developing and dying from colon cancer than non-smokers.

Smoking is also associated with an increased risk of colon adenomas. Smokers who have had colon adenomas removed have a relatively high risk of adenomas recur.

Drink a lot of alcohol

Research shows that drinking alcohol in moderation has many health benefits, including a reduced risk of many cancers. However, excessive alcohol use increases the risk of colon cancer. The recommended amount of alcohol is ≥ 2 drinks/day for men and 1 drink/day for women (the standard unit is about 14 grams of alcohol).


Young people will still be at risk, but this risk will increase in patients over 50 years of age.

Patient’s own medical history

Patients are at increased risk for cancer if they have a history of the following conditions:

  • Have had colon cancer before;
  • High-risk adenomatous polyps 1cm in size or abnormally shaped polyp cells under the microscope;
  • Ovarian Cancer;
  • Inflammatory bowel disease (IBD) such as ulcerative colitis, Crohn’s disease, etc.

Family medical history

People whose parents or siblings have a history of colon cancer have a higher risk of developing the disease. In particular, this risk will increase if a family member is under the age of 50, or there are many people in the family with the same disease. In addition, if a family member has had adenomatous polyps, the risk of developing the disease is also higher. Therefore, you should actively screen before the age of 45 for early detection and effective treatment if you have the disease.

Hereditary syndrome

About 5% of patients are due to hereditary syndromes, of which the two most common syndromes are Lynch syndrome (hereditary non-polyposis colon cancer – HNPCC) and familial polyposis (FAP).

Other rare syndromes that can also increase the risk of cancer are Peutz-Jeghers syndrome (PJS) and MUTYH gene-associated polyposis (MAP). However, it should be noted that these genetic syndromes are not only associated with colon cancer, but also with many other cancers.

Colon cancer stages

Colon cancer is divided into five main stages, based on the structure of the colon and how cancer cells spread from the colon to other organs.

Phase 0

Abnormal cells are found in the lining (innermost layer) of the colon wall. These abnormal cells can become cancerous and spread to nearby normal tissue. This stage is also known as the cancer in situ stage.

Phase I

Cancer cells have formed in the mucosa (innermost layer) of the colon wall and have spread to the submucosa (layer next to the mucosa) or to the muscle layer.

Phase II

Phase II is divided into IIA, IIB, IIC:

  • Stage IIA: The cancer has grown through the muscle layer and into the serosa of the colon.
    However, these cells are still only in the outermost layer of the colon and have not spread to nearby tissues and lymph nodes.
  • Stage IIB: Cancer has grown through the serosa (outermost layer) of the colon wall to the visceral peritoneum, but has not spread to nearby lymph nodes.
  • Stage IIC: Cancer has spread, through the serosa of the colon, to nearby organs but has not spread to nearby lymph nodes.

Phase III

Stage III is divided into IIIA, IIIB, IIIC:

  • Stage IIIA:
    • Cancer has spread beyond the mucosa to the submucosa or to the muscular layer of the colon wall. Cancer cells have also spread to 1-3 lymph nodes or to tissue adjacent to the lymph nodes.
    • Or the cancer has spread beyond the lining to the submucosa of the colon wall. Cancer cells have also spread to four to six lymph nodes.
  • Stage IIIB:
    • Cancer has spread beyond the muscular layer of the colon wall to the serosa or beyond the serosa to the visceral peritoneum. Cancer cells have also spread to 1-3 lymph nodes or to tissue adjacent to the lymph nodes.
    • Through the muscle layer or through the serosa of the colon wall. Cancer cells have also spread to four to six lymph nodes.
    • Either through the mucosa to the submucosa or to the muscular layer of the colonic wall. Cancer cells have also spread to at least 7 lymph nodes.
  • Stage IIIC:
    • Through the serosa to the visceral peritoneum. Cancer cells have also spread to four to six adjacent lymph nodes.
    • Either through the muscle layer to the serosa or through the serosa to the visceral peritoneum. Cancer cells have also spread to at least 7 lymph nodes.
    • Or through the serosa to adjacent organs. Cancer cells have also spread to at least one lymph node or to tissue adjacent to the lymph nodes.

Stage IV

Stage IV is divided into IVA, IVB, IVC:

  • Stage IVA: Cancer has spread to an area or organ far from the colon, such as the liver, lungs, ovaries, or lymph nodes distant from the colon.
  • Stage IVB: Cancer has spread to more than one area or organs away from the colon.
  • Stage IVC: Cancer has spread to the tissues of the inner lining of the abdomen and may have spread to other areas and organs.​

Diagnosing colon cancer

First, the doctor will conduct an initial examination, record additional information about the patient’s symptoms, medical history, family medical history, etc. Based on the information collected, in the school In case of suspected malignancy appearing in the colon, the doctor will assign the patient to perform laboratory tests to diagnose the disease more accurately.

  • Abdominal ultrasound: Detecting tumors located in the colon is difficult because the digestive tract will interfere with ultrasound. However, this technique will contribute to detecting indirect warning signs such as thickening of the colon wall, intestinal obstruction, etc.
  • Blood in the stool: Blood in the stool can be seen when there are polyps, cancer or some other disease of the colon.
  • Computed tomography (CT) or magnetic resonance imaging (MRI): To detect the shape, size and extent of invasion of the tumor, and detect the spread of cancer to other organs in the body. .
  • Colonoscopy : This is a technique to look inside the colon and can see polyps, abnormal tissue, or cancer. Through the endoscope, a device is used so that a sample of abnormal tissue can be taken for a biopsy.
  • Biopsy: A sample of abnormal tissue or cells is viewed under a microscope by a pathologist to look for malignant cells.​

Is colon cancer curable?

The more late the detection and treatment, the lower the prognosis for effective treatment and prolongation of life in patients. Cancer in the early stages usually progresses more slowly, if detected and treated early, the prognosis is good. The 5-year survival rate for treatment by stage is as follows: Stage I is over 90%, stage II is about 80-83%, stage III is about 60%, and stage IV is very low. , only 11%.

Colon cancer treatments

Depending on the type of cancer cells and the stage of the disease, the doctor will prescribe either monotherapy, or a combination of treatments to achieve the highest efficiency. At the Oncology Department, Tam Anh General Hospital, the treatment plan is always tailored to each individual patient based on updating the latest treatment guidelines in the world.

Treatments that may be indicated include:


Surgery is the most commonly used method in most stages of colon cancer. After surgery, patients may continue to have chemotherapy and radiation to destroy any remaining cancer cells.

The part of the colon with cancer and the lymph glands will be removed. Laparoscopic surgery or keyhole surgery helps patients avoid long scars after surgery. This new method has the advantage of shortening the recovery time after surgery, minimizing the risk of infection. In some cases, laparoscopic surgery will be combined with open surgery, but only with a short scar.


A method of using high-energy beams to kill cancer cells or slow their growth. The way radiation therapy will be given depends on the type and stage of the cancer.

For colon malignancies, radiation therapy is only used in cases where the disease has spread to the bones, brain, etc.


Chemotherapy is a treatment that uses drugs to stop the growth, or kill, or stop the division of cancer cells. When the drug is taken by mouth or given intravenously, it enters the bloodstream and targets cancer cells throughout the body. The chemotherapy drugs that will be used depend on the type and stage of the cancer.

Chemotherapy in combination with targeted drugs is indicated for patients with advanced colon cancer, with signs of metastasis to other organs in the body (such as liver, lung, etc.) treated by surgical methods alone.

This method is also used after surgery for colon cancer to prevent the risk of recurrence of the disease, as well as increase the patient’s chance of survival if there are signs of metastasis to lymph nodes adjacent to the cancer area.

Target treatment

Targeted therapy is a treatment that uses drugs to target and destroy cancer cells with specific properties. Targeted drugs commonly used in colon cancer:

  • Monoclonal antibodies.
  • Vascular antibiotics.


Immunotherapy is a treatment that uses a person’s immune system to fight cancer.

Diet for people with colon cancer

  • Add more vegetables, fruits, whole grains: Accumulated waste is the main cause of polyp formation, which develops into cancer cells over time. Research shows that adding more foods rich in fiber will help eliminate waste outside, reducing the risk of colon polyps by 40%.
  • Avoid greasy foods: It is necessary to limit fatty foods because they will produce acid in the colon, causing tumors to grow quickly.
  • Folic acid supplements from plants: Folic acid found in citrus fruits such as oranges, grapefruits, tangerines … has been shown to reduce the risk of colon cancer.
  • Adequate calcium supplementation: Research shows that a full supplement of 700-800 mg of calcium per day will reduce the risk of disease by 40-50%. Besides, vitamin D will help absorb calcium more effectively.

Prevent colon cancer

Doctor Thao Nghi shares, you can completely prevent the risk of colon cancer by making lifestyle changes:

  • No smoking;
  • Limit alcoholic beverages;
  • Maintain a reasonable weight, avoid being overweight or obese;
  • Adhere to a high-fiber diet, consume a reasonable amount of protein; scientific food processing;
  • Exercise regularly, 2-3 times/week;