What Is Colon Cancer?
The type of cancer originating in the large intestine, or the colon, is called colon cancer. The large intestine is the last part of the digestive system. This cancer most commonly affects older adults, but it can occur at any age. Colon polyps, which are small, noncancerous clumps of cells, are usually how this cancer begins. Some of these polyps can turn cancerous over time.
As polyps are quite small and produce very few or no symptoms, it is advised to get regularly screened to prevent colon cancer. Polyps can be identified and removed before they form cancer. Various treatment options are also available for colon cancer, such as surgery, radiotherapy, and chemotherapy.
What Is Colorectal Cancer and What Are Its Stages?
The term colorectal cancer is used to describe cancer of both the colon and rectum (the end of the large intestine). Its stages are:
Stage 1 - Cancer has spread to the colon or rectal mucosa but not to the walls of the organ.
Stage 2 - Cancer has spread to the walls of the colon or rectum but not to the lymph nodes or adjacent tissues.
Stage 3 - Cancer has reached the lymph nodes but not other body parts. Generally, it involves one to three lymph nodes.
Stage 4 - Cancer has spread to organs like the lungs.
What Are the Signs and Symptoms of Colon Cancer?
Most people do not experience any symptoms during the early stages of colon cancer. In case symptoms occur, they vary depending on the size of the cancer and its location. The early signs and symptoms of colon cancer are:
The symptoms associated with stage 3 or 4 are:
If cancer cells spread to other parts of the body, then the symptoms might include the following:
When to Consult a Doctor?
Anyone experiencing the above symptoms persistently should book an appointment with their doctor. One should get screened for colon cancer. It is recommended to begin regular screening from 50 years of age. If someone has a family history of this disease, the doctor might ask to start screening early.
What Are the Causes of Colon Cancer?
Doctors are still trying to find the exact cause of this cancer. Even though the exact cause is not known, the following are some of the factors that increase the risk of developing colon cancer.
Polyps - Polyps are precancerous growths formed by the accumulation of abnormal cells in the lining of the colon. These are usually small and benign; if left untreated, they can become cancerous. The following are some common types of polyps in the large intestine:
The best way to prevent it is by getting it surgically removed.
Gene Mutations - Mutations of specific genes can make members of a family more prone to this cancer. Genetic damage or changes to DNA can cause the cell to grow uncontrollably. If any family members have been diagnosed with colon cancer, they must be screened at regular intervals.
Age - Almost 90 percent of patients who have been diagnosed with colon cancer are above the age of 50 years. But, it is increasingly becoming common in people under the age of 50 years.
Lifestyle - People with inactive lifestyles are more prone.
Obesity - Overweight and obese individuals are at risk.
Smoking and Alcoholism - Using tobacco products and binge drinking increases the risk.
Diet - A recent study showed that people who consume a diet rich in saturated fats, red meat, processed meat, and low in fiber are more prone to colon cancer.
Underlying Conditions - Diabetes, radiation therapy for other cancers, inflammatory bowel diseases, and acromegaly.
How Is Colon Cancer Diagnosed?
As this cancer does not produce symptoms in the early stages, doctors recommend screening tests to look for signs of colon cancer or polyps. If a person is not in the high-risk group, these screening tests should be started at around 50 years, and if a person is in the high-risk group, then screening should be started earlier.
The doctor will first ask the patient about his family history, symptoms, and medical history. He or she will then perform a physical examination by pressing on the abdomen. Then the patient will be asked to get the following tests done:
Blood tests - To rule out other conditions that can result in similar symptoms. They will ask for liver function tests (LFT) and a complete blood count (CBC)
Colonoscopy - A long flexible tube with a camera attached to one end is inserted inside the colon through the rectum. This can help diagnose polyps and other growths.
Biopsy - If needed, the doctor might remove tissue from any abnormal growth during a colonoscopy. This tissue will then be sent for laboratory testing.
Double-Contrast Barium Enema - The bowels will be coated with a barium solution, and then X-rays will be taken.
CT (Computed Tomography) scan - This provides a more detailed image of the colon.
What Are the Treatment Options for Colon Cancer?
Depending on the stage of cancer and the patient’s general health, the various treatment options include:
For Early- Stage Cancer: A minimally invasive surgery, such as -
Polypectomy - Small and confined polyps are removed during a colonoscopy.
Endoscopic Mucosal Resection - If the polyps are larger, then the doctor might use special tools to remove the polyps and a little of the inner lining of the colon during a colonoscopy.
Laparoscopic Surgery - For polyps that cannot be removed during a colonoscopy, surgery is done by inserting special instruments through several small incisions in the abdominal wall.
Partial Colectomy- Partial Colectomy is the treatment option in cancer cases that have grown into the colon. The part of the colon that contains the cancer is removed. If the doctor is not able to reconnect the healthy portions of the colon, the surgeon performs an ostomy. An opening will be created on the wall of the abdomen, through which stool is eliminated to a bag outside the body. The nearby lymph nodes are also removed.
For Advanced Cancer - In advanced cases, where cancer has spread to other body parts, the doctor will perform surgeries to relieve signs and symptoms. But these surgeries will not cure cancer.
2) Chemotherapy - Medicines are used to destroy cancer cells and reduce the rate of recurrence.
3) Radiation Therapy - Powerful X-rays and protons are used to destroy cancer cells.
The use of chemotherapy and radiation therapy can shrink cancer, which makes it easier for the surgeon to remove it. If cancer is inoperable, then these treatment options provide symptomatic relief.
The other treatment options include targeted drug therapy, immunotherapy, and palliative care.
Can Colon Cancer Be Prevented?
The following tips might help lower the risk of colon cancer:
The diet should include fruits, vegetables, and whole grains because vitamins and minerals are abundant in them.
Keep the weight under check. A treatment plan to lose weight should be made after consulting the doctor for those who are overweight.
Avoid binge drinking and limit the consumption of alcohol.
Try to exercise at least four days a week for a minimum of 30 minutes.
Colon cancer is slow-growing cancer, and it may take years to grow. In its initial stages, it does not produce any symptoms. Additionally, the symptoms people might experience would be abdominal discomfort which they might ignore. Hence, colon cancer may be left recognized. This cancer can be prevented and treated if diagnosed at an early stage with prompt treatment. Therefore, not a single symptom related to the abdomen should be neglected especially if someone has a family history of colon cancer.
Frequently Asked Questions