What are the functions of the colon?
The large intestine is part of our digestive system. It is approximately 1.5 to 1.8 meters in length and is divided into 6 main sections, the cecum, the ascending colon, the transverse, the descending, the sigmoid colon and the rectum. The main functions of the colon are: absorption, excretion, mobility, formation and excretion of stools.
Colon cancer and polyps
Colorectal cancer is the third most common cancer in the world. Colon tumors start from polyps. Polyps are benign tumors of the intestinal mucosa and vary in size and shape. Some polyps are predisposed to cancer and some are not. An experienced gastroenterologist can tell whether a polyp is dangerous. A particular type of polyp, called adenoma, can become cancer in the future. This polyp must be removed.
What are the symptoms?
Some people with colon cancer have little or no symptoms. Each patient should also be observant of any changes in normal bowel habits and consult their physician without delay.
- Change in normal bowel habits, mainly constipation
- Blood in the stools or black or maroon stools.
- Abdominal pain
What is the best way for early diagnosis?
Colonoscopy is the best test for the early diagnosis of colon cancer. Colonoscopy is recommended for every adult, male or female, over 45 years of age. In the case of a normal examination, it is recommended to repeat it in 10 years.
Polyps, the precancerous lesions and are more common in people over 45 years of age. People with first-degree relatives (parents, siblings, children) with colorectal cancer or a history of dangerous polyps in first-degree relatives have an increased risk of developing colon cancer, especially if first-degree relatives were younger than 60 years of age at the time of diagnosis. In these cases, we do colonoscopy at 40 years of age or earlier. If the colonoscopy is normal, the recommended re-check interval is 5-10 years.
What happens after diagnosis?
If colorectal cancer is diagnosed, other tests are also carried out, which briefly include general blood work up, CEA (carcinoembryonic antigen) levels and a CT scan. After the diagnosis, the extent of the cancer must also be determined. This process is called staging. The stage of colon cancer is determined using the TNM system. T stands for tumor, N stands for lymph nodes, and M represents metastasis. It is based on radiological, surgical and pathology findings. The oncologist should be aware of the TNM stage of the patient's colon cancer in order to design the best possible treatment.
- Stage 0: Cancer is only in the intestinal mucosa.
- Stage I: Cancer has invaded the intestinal wall.
- Stage II: Cancer has occupied the entire bowel wall but has not yet spread to the lymph nodes.
- Stage III: Cancer has spread to nearby lymph nodes but not to other parts of the body.
- Stage IV: Cancer has metastasis, usually in the liver or lungs.
How is colon cancer treated?
The treatment of colon cancer is surgery, chemotherapy or radiation and is dependent on the stage, symptoms and general condition of the patient. In most cases, surgery is the first-line treatment and may be the only one required.
It is applied during colonoscopy in selected cases where the cancer is at a very early stage and can be completely removed safely during the endoscopy. After removal of the tumor, a detailed examination of the tumor is performed by a pathologist to determine if additional surgery is needed.
With surgery the cancer, as well as lymph nodes are removed. Then the two ends of the intestine are reconnected. In some cases, the surgeon can also offer laparoscopic surgery, a new technique that uses cameras and very small incisions in the abdomen.
Not all patients will require chemotherapy. Generally, stages III and IV and, in some cases, stage II of colon cancer may require chemotherapy. Chemotherapy uses drugs that are administered intravenously or orally.
Radiotherapy uses high energy X-rays.
What to expect after treatment?
Follow-up is very important and should be part of the patient's life. Monitoring may include physical examination, blood tests, radiographs and colonoscopies at regular intervals. Each patient can help themselves recover from cancer by maintaining a healthy lifestyle. It is essential to have as little stress and anxiety as possible. We should eat healthy, with a diet rich in fruits, vegetables and whole grains. It is important to maintain a normal body weight, stop smoking and reduce excessive alcohol consumption. We should not forget the annual physical examination and routine tests cardiology evaluation, mammography, gynecological examination and prostate exam in men.